Skip to main content

Full text of "Stream maintenance program update, 2012-2022 : final subsequent environmental impact report."

See other formats


Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 

Volume 2 



Horizon 

^^ WAI bK and LNVIRONMENT 


Santa Clara Valley Water District 

December 2011 


Santa Clara Valley 
Water District A 





FINAL 

SUBSEQUENT ENVIRONMENTAL IMPACT REPORT 


Santa Clara Valley Water District 
Stream Maintenance Program Update 

2012-2022 

Volume II of II 

Prepared for: 

Santa Clara Valley Water District 
5750 Almaden Expressway 
San Jose, CA 95118-3686 
Contact: Kristen O’Kane 
408/265-2607, ext. 2692 


Prepared by: 

Horizon Water and Environment, LLC 
1330 Broadway, Suite 424 
Oakland, California 94612 
Contact: Michael Stevenson 
510/986-1852 


December 2011 



Horizon Water and Environment. 2011 (December). 
Stream Maintenance Program Update-2012-2022 
Final Subsequent Environmental Impact Report. 

HWE 10.005. Oakland, CA. 



Table of Contents 


Executive Summary.ES-1 

Chapter 1 Introduction 

1.1 General Background.1-1 

1.2 Proposed Project Background.1-1 

1.3 Overview of CEQA Requirements and the 2002 SCVWD 

Stream Maintenance Program EIR.1-2 

1.3.1 CEQA Requirements for Subsequent EIR.1-3 

1.4 Public Involvement Process.1-5 

1.4.1 Scoping Comment Period.1-5 

1.4.2 Draft EIR DSEIR Comment Period.1-6 

1.4.3 Preparation of Final EIR FSEIR and Public Hearing.1-7 

1.5 Organization of this DSEIR.1-7 

1.6 Impact Terminology.1-9 

Chapter 2 Project Description 

2.1 Introduction.2-1 

2.1.1 Project Purpose.2-1 

2.1.2 Project Objectives.2-3 

2.1.3 Project Background.2-4 

2.1.4 Project Area.2-6 

2.1.5 Project Channel Types.2-9 

2.1.6 Overview of SMP Approach.2-12 

2.1.7 Maintenance Guidelines.2-13 

2.2 Maintenance Activities.2-15 

2.2.1 Bank Stabilization.2-15 

2.2.2 Sediment Removal.2-17 

2.2.3 Vegetation Management.2-19 

2.2.4 Management of Animal Conflicts.2-21 

2.2.5 Minor Maintenance.2-21 

2.2.6 Canal Maintenance.2-22 

2.2.7 Activities Not Covered in the SMP Update.2-24 

2.3 Stream Maintenance Process Overview.2-25 

2.3.1 Annual Work Sequence.2-25 

2.4 Programmatic Impact Avoidance, Minimization, and 

Compensatory Mitigation.2-30 

2.4.1 Programmatic Impact Avoidance and Minimization.2-30 

2.4.2 Best Management Practices.2-31 

2.4.3 Compensatory Mitigation.2-32 

2.5 Permits and Approvals.2-38 

Chapter 3 Environmental Setting and Impact Analysis 

3.0 Introduction.3.0-1 


Santa Clara Valley Water District i December 2011 

Stream Maintenance Program Update 2012-2022 Project No. 10.005 

Final Subsequent Environmental Impact Report 






































Table of Contents 


3.0.1 Introduction to the Environmental Setting and 

Impact Analysis.3.0-1 

3.0.2 Sections Eliminated from Further Analysis.3.0-1 

3.1 Aesthetics.3.1-1 

3.1.1 Introduction.3.1-1 

3.1.2 Regulatory Setting.3.1-2 

3.1.3 Environmental Setting.3.1-3 

3.1.4 Impact Analysis.3.1-10 

3.2 Air Quality.3.2-1 

3.2.1 Introduction.3.2-1 

3.2.2 Regulatory Setting.3.2-1 

3.2.3 Environmental Setting.3.2-5 

3.3.4 Impact Analysis.3.2-9 

3.3 Biological Resources.3.3-1 

3.3.1 Introduction.3.3-1 

3.3.2 Regulatory Setting.3.3-5 

3.3.3 Environmental Setting.3.3-14 

3.3.4 Impact Analysis.3.3-38 

3.4 Cultural Resources.3.4-1 

3.4.1 Introduction.3.4-1 

3.4.2 Regulatory Setting.3.4-1 

3.4.3 Environmental Setting.3.4-6 

3.4.4 Impact Analysis.3.4-17 

3.5 Global Climate Change.3.5-1 

3.5.1 Introduction.3.5-1 

3.5.2 Regulatory Setting.3.5-1 

3.5.3 Environmental Setting.3.5-3 

3.5.4 Impact Analysis.3.5-5 

3.6 Hazards and Hazardous Materials.3.6-1 

3.6.1 Introduction.3.6-1 

3.6.2 Regulatory Setting.3.6-1 

3.6.3 Environmental Setting.3.6-5 

3.6.4 Impact Analysis.3.6-17 

3.7 Hydrology and Geomorphology.3.7-1 

3.7.1 Introduction.3.7-1 

3.7.2 Regulatory Setting.3.7-1 

3.7.3 Environmental Setting.3.7-2 

3.7.4 Impact Analysis.3.7-21 

3.8 Land Use and Planning.3.8-1 

3.8.1 Introduction.3.8-1 

3.8.2 Regulatory Setting.3.8-1 

3.8.3 Environmental Setting.3.8-2 

3.8.4 Impact Analysis.3.8-3 

3.9 Noise.3.9-1 

3.9.1 Introduction.3.9-1 

3.9.2 Regulatory Setting.3.9-3 

3.9.3 Environmental Setting.3.9-7 

3.9.4 Impact Analysis.3.9-9 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


December 2011 
Project No. 10.005 


















































Table of Contents 


3.10 Public Services and Utilities.3.10-1 

3.10.1 Introduction.3.10-1 

3.10.2 Regulatory Setting.3.10-1 

3.10.3 Environmental Setting.3.10-3 

3.10.4 Impact Analysis.3.10-5 

3.11 Recreation.3.11-1 

3.11.1 Introduction.3.11-1 

3.11.2 Environmental Setting.3.11-1 

3.11.3 Impact Analysis.3.11-2 

3.12 Traffic and Transportation.3.12-1 

3.12.1 Introduction.3.12-1 

3.12.2 Regulatory Setting.3.12-1 

3.12.3 Environmental Setting.3.12-4 

3.12.4 Impact Analysis.3.12-15 

3.13 Water Quality.3.13-1 

3.13.1 Introduction.3.13-1 

3.13.2 Regulatory Setting.3.13-3 

3.13.3 Environmental Setting.3.13-10 

3.13.4 Impact Analysis.3.13-24 

Chapter 4 Other Statutory Considerations 

4.1 Introduction.4-1 

4.2 Irreversible Impacts.4-1 

4.3 Significant and Unavoidable Impacts.4-2 

4.4 Growth Inducing Impacts.4-2 

4.5 Cumulative Impacts Analysis.4-3 

4.5.1 Methods Used in this Analysis.4-4 

4.5.2 Cumulative Impact Analysis.4-14 

4.5.3 Cumulative Impacts.4-17 

Chapter 5 Alternatives Analysis 

5.1 Introduction.5-1 

5.1 Regulatory Requirements.5-1 

5.3 Alternatives Development Process.5-3 

5.3.1 Project Goals and Objectives.5-3 

5.3.2 Significant Environmental Impacts of the Proposed Project.5-4 

5.3.3 Significant and Unavoidable Environmental Impacts 

of the Proposed Project.5-5 

5.4 Alternatives Considered.5-5 

5.4.1 No Project Alternative.5-7 

5.4.2 Reduced Frequency Alternative.5-9 

5.4.3 Limited Work in Unmodified Channels Alternative.5-11 

5.4.4 Limited Activities Alternative.5-15 

5.5 Alternatives Considered and Dismissed.5-16 

5.5.1 Geomorphic Alternative.5-16 

5.5.2 Watershed Approach Alternative.5-17 

5.5.3 Return to As-Built Conditions.5-17 

5.5.4 Modified Pajaro River Basin Alternative.5-18 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


December 2011 
Project No. 10.005 














































Table of Contents 


5.5.5 No Herbicides Alternative.5-18 

5.5.6 Reduced Extent Alternative.5-18 

5.5.7 Alternative Locations.5-18 

5.5.8 Reduced Time Frame Alternative.5-18 

5.6 Environmentally Superior Alternative.5-19 

Chapter 6 Report Preparation.6-1 

Chapter 7 References.7-1 


Volume II Appendices 

2012 Stream Maintenance Program Manual 
Notice of Preparation and Comments Received 
2012-2022 SMP Update Mitigation Approach Memorandum 
General Plan Policies and Ordinances 
Air Quality and Greenhouse Gas Emissions Calculations 

Taxonomic Crosswalk between the Jepson Manual First Edition and Second Edition 
Special-Status and Locally Significant Plant Species 
Considered but Rejected for Occurrence in the Project Area 
Detailed Descriptions of Special-Status and Locally Significant Plant Species 
Potentially Occurring in the Project Area 

Detailed Descriptions of Special-Status Wildlife Species Potentially Occurring in the 
Project Area 

Pesticide Regulatory Information 
Traffic and Transportation Calculations 
Mitigation Monitoring and Reporting Program 
Fish Relocation Guidelines 


Appendix A 
Appendix B 
Appendix C 
Appendix D 
Appendix E 
Appendix F 
Appendix G 

Appendix H 

Appendix I 


Appendix J 
Appendix K 
Appendix L 
Appendix M 


Tables 

Table ES-1 Summary of Potential Impacts and Mitigation Measures ES-23 

Table 2-1 Sediment Removal, 2002-2009 2-5 

Table 2-2 Vegetation Management, 2002-2009 2-5 

Table 2-3 Bank Stabilization, 2002-2009 2-6 

Table 2-4 SMP Bank Stabilization Methods (SMP Update 2012] 2-15 

Table 2-5 Actual Sediment Removal Work, 2002-2009 2-18 

Table 2-6 Projected Sediment Removal Work, 2012-2022 2-19 

Table 2-7 Projected Vegetation Management Work Type by Watershed 2-20 

Table 2-8 2002 SMP Mitigation Program 2-34 

Table 2-9 2012-2022 Mitigation Approach for Sediment Removal and 

Vegetation Management Activities 2-37 

Table 2-10 Agency Approvals 2-39 

Table 2-11 Comparison of Key Differences between 2002 SMP 

and 2012 SMP Update 2-41 

Table 2-12 BMPs Listings 2-48 

Santa Clara Valley Water District iv December 2011 

Stream Maintenance Program Update 2012-2022 Project No. 10.005 

Final Subsequent Environmental Impact Report 










Table of Contents 


Table 3.2-1 State and Federal Ambient Air Quality Standards 3.2-2 

Table 3.2-2 Bay Area Attainment Status of the State and Federal 

Ambient Air Quality Standards 3.2-8 

Table 3.2-3 BAAQMD CEQA Thresholds of Significance for Criteria Air Pollutants 3.2-10 

Table 3.2-4 Estimated Proposed Project Average Daily Emissions of 

Criteria Air Pollutants, pounds per day 3.2-11 

Table 3.2-5 Estimated Proposed Project Annual Emissions of 

Criteria Air Pollutants, tons per year 3.2-12 

Table 3.3-1 Fish Relocation Creeks 3.3-3 

Table 3.3-2 Selected Recent SCVWD Fisheries Studies 3.3-3 

Table 3.3-3 Locations of Pre-Construction Presence/Absence Surveys for 

Special-Status Amphibians, 2004-2010 3.3-5 

Table 3.3-4 Crosswalk between Natural Community/Wildlife Habitat Types 

and Vegetation Mapping Units 3.3-17 

Table 3.3-5 Projected Impact Acreages by Habitat Type and Activity, Non-tidal Reaches 3.3-63 

Table 3.3-6 Projected Impact Acreages by Habitat Type and Activity, Tidal Reaches 3.3-65 

Table 3.3-7 Projected Sediment Removal, 2012-2022 3.3-67 

Table 3.3-8 Projected Vegetation Management, 2012-2022 3.3-68 

Table 3.3-9 Estimated Impacts to Riparian Woodland, Forest, and Scrub-Shrub 

from Projected Vegetation Management, 2012-2022 3.3-77 

Table 3.3-10 Estimated Impacts to Northern Coastal Salt Marsh. Sycamore Alluvial 
Woodland, and Serpentine Communities from Projected 

SMP Update Activities. 2012-2022 _ 3.3-82 

Table 3.3-4311 Projected Sediment Removal Work on Streams Supporting Steelhead, 

2012-2022 3.3-100 

Table 3.3-4412 Projected Instream Herbicide Application Work on Streams Supporting 

Steelhead, 2012-2022 3.3-103 

Table 3.3-4213 Projected Non-Instream Herbicide Application Work on Streams Supporting 

Steelhead, 2012-2022 3.3-104 

Table 3.3-4314Projected Manual Vegetation Management Work on Streams Supporting 

Steelhead, 2012-2022 3.3-105 

Table 3.3-4445 Projected Sediment Removal Impacts in Areas of Potential California 

Tiger Salamander Occurrence, 2012-2022 3.3-116 

Table 3.3-4516 Projected Vegetation Management Impacts in Areas of Potential California 

Tiger Salamander Occurrence, 2012-2022 3.3-116 

Table 3.3-4617 Projected Sediment Removal Impacts in Areas of Potential California 

Red-legged Frog Occurrence, 2012-2022 3.3-123 

Table 3.3-4748 Projected Vegetation Management Impacts in Areas of Potential California 

Red-legged Frog Occurrence, 2012-2022 3.3-124 

Table 3.3-4319 Projected Sediment Removal Impacts in Areas of Potential Foothill 

Yellow-legged Frog Occurrence, 2012-2022 3.3-132 

Table 3.3-4320 Projected Vegetation Management Impacts in Areas of Potential Foothill 

Yellow-legged Frog Occurrence, 2012-2022 3.3-132 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


v 


December 2011 
Project No. 10.005 



Table of Contents 


Table 3.3-2U21 Special-Status Plant Species, Their Status, Habitat Description, and 

Potential for Occurrence in the Project Area 3.3-191 

Table 3.3-2422 Special-Status Animal Species, Their Status, Habitat Description, and 

Potential for Occurrence in the Project Area 3.3-201 

Table 3.4-1 Cultural Resource Monitoring for the SCVWD SMP, 2002-2010 3.4-16 

Table 3.5-1 Applicable BAAQMD CEQA Thresholds of Significance for Greenhouse Gases 3.5-3 

Table 3.5-2 2012 and 2020 Average Daily C02e Emissions 3.5-6 

Table 3.5-3 2012 and 2020 Annual C0 2 e Emissions 3.5-6 

Table 3.6-1 Pesticide Types Applied under the Current SMP 3.6-15 

Table 3.6-2 Pesticide Amounts Applied under the Current SMP (FY 2007-2009] 3.6-15 

Table 3.6-3 Schools within One-Quarter Mile of the Project Area 3.6-23 

Table 3.7-1 Principal Creeks in Project Area Watersheds 3.7-18 

Table 3.9-1 Examples of Common Noise Levels 3.9-2 

Table 3.9-2 FTA-Suggested Construction Noise Criteria 3.9-3 

Table 3.9-3 State Land Use Compatibility Standards for Community Noise Environment 3.9.4 

Table 3.9-4 General Plan and Noise Ordinance Standards 3.9-5 

Table 3.9-5 Typical Noise Associated with SMP Activities 3.9-9 

Table 3.10-1 Status of Landfills in Santa Clara County 3.10-4 

Table 3.12-1 Transit Service within Santa Clara County 3.12-7 

Table 3.12-2 Existing SMP Trip Generation Estimates per day 3.12-11 

Table 3.12-3 Existing SMP Trip Generation Estimates per year 3.12-12 

Table 3.12.4 Existing SMP Vehicle Miles Traveled Estimates per day 3.12-14 

Table 3.12.5 Existing SMP Vehicle Miles Traveled Estimates per year 3.12-14 

Table 3.12-6 Proposed Project Trip Generation Estimates per year 3.12-16 

Table 3.12-7 Proposed Project Vehicle Miles Traveled Estimates per year 3.12-16 

Table 3.13-1 Beneficial Uses for Surface Water Bodies and Groundwater Basins 

in the Project Area 3.13-13 

Table 3.13-2 303(d] List of Impaired Water Bodies and their Impairments 

in the Project Area 3.13-15 

Table 3.13-3 Exceedances of Sediment Constituent Thresholds by Surface Water Body for 

Sediments Removed as part of the SMP in 2009 and 2010 3.13-19 

Table 4-1 Planning Documents Considered for Cumulative Impact Analysis 4-5 

Table 4-2 Projected Santa Clara County Population and Housing Growth, 2010-2030 4-10 

Table 4-3 SCVWD 5-Year Capital Improvement Program and Project Activities that could 

potentially affect resources similar to the Proposed Project in 
fiscal years 2011-2015 4-11 

Table 5-1 Comparison of Alternatives 5-6 

Table 5-2 Reduced Frequency Alternative 10-Year Recurrence of Sediment Removal and 

Vegetation Management Activities 5-10 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


VI 


December 2011 
Project No. 10.005 



Table of Contents 


Figures 



ES-1 

Project Area 

ES-3 

2-1 

Project Area 

2-7 

2-2 

Project Area, Lower Peninsula Watershed 

follows 2-73 

2-3 

Project Area, West Valley Watershed 

follows 2-73 

2-4 

Project Area, Guadalupe Watershed 

follows 2-73 

2-5 

Project Area, Coyote Watershed 

follows 2-73 

2-6 

Project Area, Pajaro Watershed 

follows 2-73 

2-7 

Example of SCVWD-Maintained Channel 

follows 2-73 

2-8 

Coyote Creek 

2-10 

2-9 

Typical Wide Channel Cross Section with Secondary Channel 

follows 2-73 

2-10 

Guadalupe River 

2-11 

2-11 

Typical Trapezoidal Channels 

follows 2-73 

2-12 

San Tomas Aquino Creek 

2-11 

2-13 

Sierra Creek 

2-12 

2-14 

Lower Peninsula Watershed Maintenance Activity—Sediment Removal follows 2-76 


2-15 

West Valiev Watershed Maintenance Activity—Sediment Removal 

follows 2-76 

2-16 

Guadalupe Watershed Maintenance Activity—Sediment Removal 

follows 2-76 

2-17 

Covote Watershed Maintenance Activity—Sediment Removal 

follows 2-76 

2-18 

Paiaro Watershed Maintenance Activity—Sediment Removal 

follows 2-76 

2-19 

Lower Peninsula Watershed Maintenance Activity. Other Instream Vegetation 


Maintenance 

follows 2-76 

2-20 

West Valiev Watershed Maintenance Activity. Other Instream Vegetation 


Maintenance 

follows 2-76 

2-21 

Guadalupe Watershed Maintenance Activity. Other Instream Vegetation 



Maintenance 

follows 2-76 

2-22 

Covote Watershed Maintenance Activity. Other Instream Vegetation 



Maintenance 

follows 2-76 

2-23 

Paiaro Watershed Maintenance Activity, Other Instream Vegetation 



Maintenance 

follows 2-76 

2-24 

Lower Peninsula Watershed Maintenance Activity. Other Non-Instream Vegetation 


Maintenance 

follows 2-76 

2-25 

West Valiev Watershed Maintenance Activity. Other Non-Instream Vegetation 


Management 

follows 2-76 

2-26 

Guadalupe Watershed Maintenance Activity. Other Non-Instream Vegetation 


Management 

follows 2-76 

2-27 

Covote Watershed Maintenance Activity. Other Non-Instream Vegetation 


Maintenance 

follows 2-76 

2-28 

Paiaro Watershed Maintenance Activity. Other Non-Instream Vegetation 


Maintenance 

follows 2-76 

2-29 

Lower Peninsula Watershed Maintenance Activity. Instream Herbicide 



Application 

follows 2-76 





Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


VII 


December 2011 
Project No. 10.005 





Table of Contents 


2-30 

West Valiev Watershed Maintenance Activity, Instream Herbicide 



Application 

follows 2-76 

2-31 

Guadalupe Watershed Maintenance Activity. Instream Herbicide 



Application 

follows 2-76 

2-32 

Covote Watershed Maintenance Activity. Instream Herbicide 



Application 

follows 2-76 

2-33 

Paiaro Watershed Maintenance Activity. Instream Herbicide 



Application 

follows 2-76 

2-34 

Lower Peninsula Watershed Maintenance Activity, Non-Instream 



Herbicide Application 

follows 2-76 

2-35 

West Valiev Watershed Maintenance Activity. Non-Instream Herbicide 


Application 

follows 2-76 

2-36 

Guadalupe Watershed Maintenance Activity. Non-Instream Herbicide 


Application 

follows 2-76 

2-37 

Covote Watershed Maintenance Activity. Non-Instream Herbicide 



Application 

follows 2-76 

2-38 

Paiaro Watershed Maintenance Activity. Non-Instream Herbicide 



Application 

follows 2-76 

2-39 

Canals 

follows 2-73 

2-40 

The Almaden-Calero Canal 

2-23 

2-41 

Annual SMP Work Sequence 

follows 2-73 

3.1-1 

Representative Photos of SMP Channels 

3.1-7 

3.3-1 

Sample of Vegetation Mapping Performed for the SMP 

follow 3.3-18 

3.3-2 

Projected SMP Update Activities in Serepentine Communities 

follows 3.3-84 

3.3-3 

Mapped Serpentine Soils and Known Locations of Special-Status 



Serpentine-Associated Plants 

follows 3.3-86 

3.3-4 

Known Locations of Non-Serpentine Special-Status Plants 

follows 3.3-90 

3.3-5 

Bay Checkerspot Butterfly Distribution in Santa Clara County 

follows 3.3-94 


Projected Sediment Removal. 2012-2022. alone Steelhead Streams 

follows 3.3-102 

3.3-7 

Projected Instream Herbicide Application. 2012-2022. 



alone Steelhead Streams 

follows 3.3-102 

3.3-8 

Projected Non-Instream Herbicide Application. 2012-2022. 



along Steelhead Streams 

follows 3.3-102 

3.3-9 

Projected Manual Veeetation Manaeement, 2012-2022, 



alone Steelhead Streams 

follows 3.3-102 

3.3-10 

Known Occurrences and Expected Distribution of the California 



Tieer Salamander 

follows 3.3-118 

3.3-11 

Projected Sediment Removal in Areas of Potential California 



Tieer Salamander Occurrence. 2012-2022 

follows 3.3-118 

3.3-12 

Projected Veeetation Manaeement in Areas of Potential California 



Tieer Salamander Occurrence. 2012-2022 

follows 3.3-118 

3.3-13 

Known and Expected California Red-Leeeed Froe Distribution 



in Santa Clara Countv 

follows 3.3-126 


viii 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


December 2011 
Project No. 10.005 



Table of Contents 


3.3-14 


3.3-15 


3.3-16 


3.3-17 


3.3-18 


3.3-19 


3.3-20 


3.3- 21 

3.3- 22 


3.6- 1 

3.6- 2 

3.6- 3 

3.6- 4a 

3.6- 4b 

3.7- la 

3.7- lb 

3.7- 2 

3.7- 3 
5-1 


Projected Sediment Removal in Areas of Potential California 

Red-Legged Frog Occurrence. 2012-2022 _ follows 3.3-126 

Projected Instream Herbicide Application in Areas of Potential California 

Red-Legged Frog Occurrence. 2012-2022 _ follows 3.3-126 

Projected Non-Instream Herbicide Application in Areas of Potential California 

Red-Legged Frog Occurrence. 2012-2022 _ follows 3.3-126 

Projected Manual Vegetation Management in Areas of Potential California 

Red-Legged Frog Occurrence. 2012-2022 _ follows 3.3-126 

Known and Expected Foothill Yellow-Legged Frog Distribution 

in Santa Clara County _ follows 3.3-132 

Western Pond Turtle and California Horned Lizard CNDDB Occurrences 

in Santa Clara County _ follows 3.3-138 

Western Snowy Plover. California Clapper Rail.and Alameda Song Sparrow 
Habitat in Santa Clara County _ follows 3.3-142 


Recent Burrowing Owl Records in Santa Clara County _ follows 3.3-154 

Potential Salt Marsh Harvest Mouse and Salt Marsh Wandering Shrew 

Habitat in Santa Clara County _ follows 3.3-172 

Known Hazardous Sites in the Project Area 3.6-9 

Fire Hazard Severity Zones in State Responsibility Areas 3.6-11 

Fire Hazard Severity Zones in Local Responsibility Areas 3.6-13 

Schools within One-Quarter Mile of Project Area, Northern Portion 3.6-29 

Schools within One-Quarter Mile of Project Area, Southern Portion 3.6-31 

Representative Hydrographs from Project Area Watersheds 3.7-5 

Representative Hydrographs from Project Area Watersheds 3.7-7 

Guadalupe River Peak Flow Discharges 3.7-9 

Comparison of Peak Flows—Coyote Creek and Llagas Creek 3.7-11 

Limited Work in Unmodified Channels Alternative 5.13 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


IX 


December 2011 
Project No. 10.005 






This page intentionally left blank. 


Santa Clara Valley Water District x December 2011 

Stream Maintenance Program Update 2012-2022 Project No. 10.005 

Final Subsequent Environmental Impact Report 



Acronyms 


AB 

ACHP 

ADA 

AG 

AIS 

APE 

B.P. 

BAAQMD 

BCDC 

BMP 

BO 

CAA 

CAAQSs 

CAC 

Cal/OSHA 

CalRecycle 

Caltrans 

CARB 

CCC 

CCR 

CDFGorDFG 

CDPR 

CEQA 

CERCLA 

CESA 

CFR 

cfs 

CH 4 

CHRIS 

CIP 

CIWMB 

CIWMP 

CMP 

CNDDB 

CNEL 

CNPS 

C0 2 

C0 2 e 

County 

CRHR 

CVC 

CWA 


Assembly Bill 

Advisory Council on Historic Preservation 

Americans with Disabilities Act 

Attorney General 

Aerial Information Systems, Inc. 

area of potential effects 

Before Present 

Bay Area Air Quality Management District 

San Francisco Bay Conservation and Development Commission 

Best Management Practice 

Biological Opinion 

Clean Air Act 

California Ambient Air Quality Standards 

County Agricultural Commissioner 

California Occupational Safety and Health Administration 

California Department of Resources Recycling and Recovery Agency 

California Department of Transportation 

California Air Resources Board 

Central California Coast 

California Code of Regulations 

California Department of Fish and Game 

California Department of Pesticide Regulation 

California Environmental Quality Act 

Comprehensive Environmental Response, Compensation, and Liability Act 

California Endangered Species Act 

Code of Federal Regulations 

cubic feet per second 

methane 

California Historical Resources Information System 

capital improvement program 

California Integrated Waste Management Board 

Countywide Integrated Waste Management Plan 

Congestion Management Program 

California Natural Diversity Database 

community noise equivalent level 

California Native Plant Society 

carbon dioxide 

carbon dioxide equivalents 

Santa Clara County 

California Register of Historic Resources 
California Vehicle Code 
Clean Water Act 


CWHR California Wildlife Habitat Relationships 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XI 


December 2011 
Project No. 10.005 



Acronyms 


cy 

cubic yards 

dB 

decibel 

dBA 

A-weighted decibel 

dbh 

diameter at breast height 

DDD 

dichlorodiphenyldichloroethane 

DDE 

dichlorodiphenyldichloroethylene 

DDT 

dichlorodiphenyltrichloroethane 

DEH 

Santa Clara County Department of Environmental Health 

DO 

dissolved oxygen 

DOT 

U.S. Department of Transportation 

DEIR 

Draft Environmental Impact Report 

DSEIR 

Draft Subsequent Environmental Impact Report 

DTSC 

California Department of Toxic Substances Control 

DWR 

California Department of Water Resources 

EA 

Environmental Assessment 

EFH 

Essential Fish Habitat 

EIR 

Environmental Impact Report 

EIS 

Environmental Impact Statement 

EMT 

Early Period/Middle Period Transition 

FEIR 

Final Environmental Impact Report 

FESA 

Federal Endangered Species Act 

FHWA 

Federal Highway Administration 

FIFRA 

Federal Insecticide, Rodenticide, and Fungicide Act 

FTA 

Federal Transit Administration 

FSEIR 

Final Subsequent Environmental Impact Report 

FY 

fiscal year 

GHG 

greenhouse gas 

HFC 

hydrofluorocarbons 

Hg 

mercury 

HCP 

habitat conservation plan 

HMMP 

Habitat Mitigation and Management Plan 

HMP 

hydromodification plan 

HOV 

high occupancy vehicle 

IAWG 

Inter-Agency Work Group 

IPCC 

Intergovernmental Panel on Climate Change 

IPMP 

Invasive plant management program 

ISA 

International Society of Arboriculture 

ISP 

Invasive Spartina Program 

LCFS 

Low Carbon Fuel Standard 

Ldn 

day-night (sound] level 

Leq 

equivalent sound level 

Lmax 

maximum sound level 

Lmin 

minimum sound level 

LOS 

level of service 

LRA 

local responsibility area 

LUFT 

leaking underground fuel tank 

Lxx 

percentile-exceeded sound level 

MeHg 

methylmercury 


Santa Clara Valley Water District xii 

Stream Maintenance Program Update 2012-2022 
Final Subsequent Environmental Impact Report 


December 2011 
Project No. 10.005 



Acronyms 


MFA 

mg/L 

MHW 

MTBA 

MTC 

N 2 0 

NAAQS 

NCCP 

NEPA 

NHPA 

NMFS 

NOP 

NOx 

NPDES 

NPW 

NRHP 

OHP 

PAHs 

PCBs 

PCEs 

PCR 

PM 

PM 10 

PM 2.5 

Porter-Cologne Act 
PRC 

PRESCRIBE 

Proposed Project 

RCRA 

ROG 

RWQCB 

SB 

SCCC 

SCCVCD 

SCS 

SCVURPPP 

SCVWD 

SEIR 

SFBAAB 

SHPO 

SMP 

SR 

SWRCB 

TMDL 

URMP 

U/S 


mitigation feasibility assessment 

milligrams per liter 

mean high water 

Migratory Bird Treaty Act 

Metropolitan Transportation Commission 

nitrous oxide 

National Ambient Air Quality Standards 
natural community conservation plan 
National Environmental Policy Act 
National Historic Preservation Act 
National Marine Fisheries Service 
Notice of Preparation 
nitrogen oxides 

National Pollutant Discharge Elimination System 
Notification Notice of Proposed Work 
National Register of Historic Places 
California Office of Historic Preservation 
polycyclic aromatic hydrocarbons 
Polychlorinated biphenyls 
primary constituent elements 
Post-Construction Report 
particulate matter 

particulate matter less than 10 microns in diameter 
particulate matter less than 2.5 microns in diameter 
Porter-Cologne Water Quality Control Act 
California Public Resources Code 

Pesticide Regulation's Endangered Species Realtime Internet Bulletin 
Engine database 

Stream Maintenance Program Update 
Resource Conservation and Recovery Act 
reactive organic gases 
Regional Water Quality Control Board 
Senate Bill 

South-Central California Coast 

Santa Clara County Vector Control District 

Soil Conservation Service (now the Natural Resources Conservation 
Service] 

Santa Clara Valley Urban Runoff Pollution Prevention Program 

Santa Clara Valley Water District 

Subsequent Environmental Impact Report 

San Francisco Bay Area Air Basin 

State Historic Preservation Officer 

Stream Maintenance Program 

State Route 

State Water Resources Control Board 
Total Maximum Daily Load 
Urban Runoff Management Plan 
upstream 


xiii 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


December 2011 
Project No. 10.005 



Acronyms 


USACE 

use 

USEPA 

USFS 

USFWS 

USGS 

USSCS 

VMT 

VTA 

WDRs 

WMA 

WPCP 


U.S. Army Corps of Engineers 
U.S. Code 

U.S. Environmental Protection Agency 

U.S. Forest Service 

U.S. Fish and Wildlife Service 

U.S. Geologic Survey 

U.S. Soil Conservation Service, now known as U.S. Natural Resources 
Conservation Service [NRCS] 
vehicle miles traveled 

(Santa Clara] Valley Transportation Authority 
waste discharge requirements 
watershed management area 
water pollution control plant 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XIV 


December 2011 
Project No. 10.005 



GLOSSARY OF SIGNIFICANT TERMS 


1 percent flood 


100-Year Flood 
Adaptive Management 


Aggradation 


Anadromous 


Annual Plant 

Annual Work Plan 


Appurtenant Structures 
Aquatic Vegetation 

Avian 

Avoidance 


Refers to a flood of a magnitude that has an estimated 
probability of 1 in 100 of occurring in any given year. 
Technically more precise way of referring to the "100-year 
flood." Generally, 1 percent, 2 percent, and 10 percent events 
refer to levels of flood flows with an expected recurrence of 
100, 50, and 10 years, respectively. 

Flood of a magnitude with an expected recurrence of once in 
100 years. Synonymous with 1 percent flood. 

A dynamic process that recognizes that the future cannot be 
perfectly predicted. In response to imperfect predictions, 
planning and management strategies are modified as better 
information becomes available. It is a continuous 
improvement process whereby monitoring and analysis of 
the results of past actions are fed back into the current 
decision-making process. 

Process of a channel raising its elevation through deposition 
of sediments. A type of fluvial geomorphic instability (see 
"Degradation"]. 

A term used to describe the movement of certain fishes from 
saltwater to freshwater to breed, and from freshwater to 
saltwater to grow and mature. 

A plant that completes its life cycle and dies in one growing 
season or one year (e.g., corn, lettuce, wild oat]. 

The stream maintenance work indentified that forms the 
basis of the annual budget. Specific information, such as 
location and size of sediment removal, vegetation 
management and erosion repair, is provided in the Annual 
Work Plan. 

Accessory structures, such as storm outfalls, stream gages, 
trash racks, flap gates, tide gates, vaults, and headwalls. 

Herbaceous vegetation that grows in the wetted channel 
bottom and is typically dependent on either sustained flow 
or prolonged periods of water on site for survival. 

Bird or bird-like. 

Strategies for the planning, design, maintenance, and 
operation of District facilities to provide water supply and 
flood control, and which refrain from causing significant 
adverse environmental impacts. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


xv 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Bank Stabilization 


Bank/Bench 

Bank Repair 

Bankfull 

Bankfull Bank 
Bankfull Elevation 

Basin 

Bedload 


Bank stabilization involves any action by the District to 
stream banks that are eroding (repair], as well as 
preventative erosion protection. The District implements 
stream bank stabilization when the problem [1] causes or 
could cause significant damage to a property or adjacent 
property, [2] is a public safety concern, [3] negatively affects 
transportation or recreational use, (4] negatively affects 
water quality, or (5] negatively affects riparian habitat. Bank 
protection stabilizes a channel bank by using rock, rip rap, 
concrete, soft materials, vegetation, or a combination of 
materials or methods. Bank stabilization can also include 
preventative maintenance to ensure that banks do not erode 
in the future. This new work is considered routine 
maintenance because it is either restoring the flood control 
function of a modified channel, or it is repairing a natural 
bank to its approximate condition prior to becoming an 
erosion problem. 

The area of the bank above the bankfull elevation and below 
the toe of levee inboard if in a reach with levee, and property 
line if not in a levee reach. 

Maintenance of existing bank stabilization structures with in- 
kind, in-place materials. This type of maintenance occurs 
when such structures fail. 

When the channel is flowing full, the water surface is at 
floodplain level and the flow rate is the bankfull discharge. 

The area of bank between instream and bankfull elevation 

The point where the normal channel meets the floodplain, 
the elevation at the top of the channel banks. When the 
channel is flowing full, the water surface is at floodplain level 
and the flow rate is the bankfull discharge. 

For the purposes of the Stream Maintenance Program, a 
depression or valley that drains to a common waterbody. In 
Santa Clara County, two major hydrologic basins drain either 
into San Francisco or to Monterey Bay. In the northern 
portion of the county, streams of the Santa Clara Basin drain 
to San Francisco Bay. To the south, streams in the Pajaro 
River Basin drain ultimately to Monterey Bay. 

Material moving on or within a few particle diameters above 
the streambed, rolling or sliding, but not carried in the water 
column itself. Generally moves more slowly than the 
streamflow itself. Compare with "Suspended Sediment." 
Bedload does not mean the rate of discharge of bed material 
(see "Bedload Discharge"]. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XVI 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Bedload Discharge The rate of bedload transport; the quantity of bedload 

passing a point on the channel in a unit of time. 

Best Management Practice (BMP) An activity, procedure, or other standard management and 

work practice that provides the most effective means of 
preventing or reducing pollution or other negative 
environmental consequences. BMPs are incorporated into 
project activities to avoid and minimize environmental 
impacts. 

Biotechnical A method of bank stabilization emphasizing the 

incorporation of soft structures (e.g., vegetation). See "Soft 
Structures." 


Biotechnical Channel 

Brackish Water 
Bypass Channel 


Bypass Structures 


California Environmental 
Quality Act (CEQA) 


A natural or artificial waterway that periodically or 
continuously contains moving water, or which forms a 
connecting link between two bodies of water. 

Water that is a mixture of freshwater and saltwater, with a 
salinity less than seawater. 

A flood control facility through which a portion of a stream's 
flow is diverted from one point and reintroduced into the 
stream at the downstream end of the bypass channel. Bypass 
channels can be used during the construction or 
maintenance process. Permanent bypass channels can also 
be designed to accommodate flood flows. 

On construction sites, a generic term for any type of 
structure(s) used to pond water and convey it around a work 
site (e.g., cofferdams, bypass pipes, channels). 


The California Environmental Quality Act is California Public 
Resources Code Sections 21000 et seq. CEQA establishes a 
duty for public agencies to avoid or minimize environmental 
damage where feasible, recognizing that a public agency has 
an obligation to balance a variety of public objectives, 
including economic, environmental, and social factors. CEQA 
is intended to facilitate the disclosure of the significant 
environmental effects of proposed activities to decision¬ 
makers and the public, the identification of ways to avoid or 
reduce environmental damage, and the prevention of 
environmental damage by requiring the implementation of 
feasible alternatives or mitigation measures. 


Capital Improvement Project CIP) For the purposes of the Stream Maintenance Program, a large 

flood control construction project that affects the flood 
conveyance capacity of the stream. These projects are not 
considered routine stream maintenance. 


Channel 


Creeks and canals. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XVII 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Channel Erosion Includes the processes of streambank erosion, streambed 

scour, and degradation. 

Channel Stabilization See "Bank Stabilization." 


Clean Water Act 


Co-dominance 


Compensatory Mitigation 


Confluence 

Culvert 

Cut-Stump Treatment 


Debris Basin 


Degradation 


Depauperate 


A broad federal statute with the goal of maintaining and 
restoring waters of the U.S. (see "Waters of the United 
States"]. Federal Water Pollution Control Act. 

Equal in size and relative importance, usually associated with 
either the trunk/stems or scaffold limbs/branches in the 
crown (Matheny and Clark 1994], 

The restoration, creation, enhancement, or preservation of 
wetlands and other resources expressly for the purpose of 
compensating for unavoidable adverse impacts that remain 
after all appropriate and practicable avoidance and 
minimization of impacts have been achieved in compliance 
with law or requirements of regulatory agencies. (Federal 
Register March 6,1995, Federal Guidance for the 
Establishment, Use and Operation of Mitigation Banks], In 
the Stream Maintenance Program, compensatory mitigation 
is mitigation in perpetuity that is to be provided by SCVWD 
to offset significant residual impacts that cannot be avoided. 

A meeting of two or more streams or rivers. 

Any covered structure not classified as a bridge, which 
conveys a waterway under a road or other paved area. 

Elimination of woody vegetation by cutting at ground level 
and treating the cambium, or outer most plant tissue, with a 
concentrated, systemic herbicide. Best results are obtained 
when application of herbicide immediately follows (within 
minutes] the removal of target vegetation. Trees removed 
and treated by cut stump are reported as hand removal. 

A depression formed by the construction of a barrier or dam 
built at a suitable location to retain rock, sediment, plant 
material, and the like, which can be conveyed along steep 
hillside streams during high flows. Usually placed in hillside 
areas where access is better for removing sediment, 
generally prior to entering urbanized reaches (see also 
"Sediment Basin"]. 

Process of a channel lowering its elevation through increased 
erosion, channel bed scour, or down-cutting. A type of fluvial 
geomorphic instability (see "Aggradation"]. 

An ecosystem that lacks sufficient stored chemical elements 
required for life. Depauperate ecosystems cannot support 
rapid growth of flora and fauna, high biomass density, or 
high biological diversity. 


Santa Clara Valley Water District xviii December 2011 

Stream Maintenance Program Update 2012-2022 Project No. 10.005 

Final Subsequent Environmental Impact Report 



Glossary of Significant Terms 


Design Capacity An engineering term used to describe the amount of water 

that a modified channel was designed to convey. Generally, 
the design capacity for improved SCVWD facilities is to 
accommodate the 1 percent or 100-year flood. This is the 
level of protection. Capacity is in cfs or Q (see "Flood 
Capacity"]. 

Design Flood The maximum calculated discharge intended to be conveyed 

in the design of a capacity-constructed channel. The 
maximum level of flood protection used as a design criterion 
in the design of a constructed or improved channel or 
waterway. 

Diameter at Breast Height (dbh) A tree trunk diameter is measured by the standard diameter 

at breast height [dbh] or approximately 4.5 feet above 
ground level. 

Drop Structure A structure designed to convey flows over a vertical distance 

from a higher to a lower elevation. 

Emergency A situation is considered an "emergency" if it is a sudden, 

unexpected occurrence involving a clear and imminent 
danger that demands immediate action to prevent or 
mitigate loss of or damage to life, health, property, or 
essential public services (Public Resource Code Section 
21060.3], Emergency repair or activities associated with an 
emergency are not addressed by the Stream Maintenance 
Program. Most emergency projects are exempt from review 
pursuant to CEQA (Public Resource Code Section 
21080(b](2], (3], (4]], although there maybe post- 
permitting requirements. 

Environmental Impact Report (EIR) A detailed statement prepared under CEQA 

describing and analyzing the significant environmental 
impacts of a project and discussing ways to mitigate or avoid 
the effects (see also "Program Environmental Impact 
Report"]. 

Creek that only flows for short periods of time during or 
immediately following a rain event. 

The detachment and movement of soil and rock fragments by 
water and other geological agents, which results in the 
wearing away of the land. When water is the eroding agent, 
erosional processes include sheet and rill erosion, gully 
erosion, and channel erosion. 

Artificial, stepped pools to enable fish traveling upstream, 
against the flow of water, to span a large vertical distance in 
a series of gradual steps. Used at dams or other in-stream 
barriers. 


Ephemeral 

Erosion 

Fish Ladders 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XIX 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Flood Capacity The capacity of a channel to carry calculated flood flows. 

Capacity is dependent on cross-sectional area and frictional 
components (e.g., channel vegetation]. 

Flood Control Facility For the purposes of the Stream Maintenance Program, any 

watercourse, whether natural or man-made, in which water 
does or may flow and which is under ownership or 
controlled by the District for flood control purposes. 

Fluvial Pertaining to rivers. 

Follow-up Hand Removal Generally this category of work is removal of dead vegetative 

material after herbicide application. This work is not 
reported. 

Gabion Basket or Mattress Galvanized wire mesh panels filled with rock used for 

structural purposes. They can be connected together and 
used for retaining walls, revetments, or bank stabilization. 

Geomorphology The study of the forms of the earth’s surface and the 

processes that shape them. Fluvial geomorphology involves 
the study of streams and sediment processes: transport, 
erosion, storage, and deposition. 

Gradeall A multipurpose mobile excavation machine with a reach of 

35 feet. 

Habitat The specific area or environment in which a particular type 

of plant or animal lives. To be complete, an organism's 
habitat must provide all of the basic requirements of life for 
that organism. 

Habitat Conservation Plan (HCP) Plans under the Endangered Species Act (ESA] negotiated 

between the federal government and private landowners or 
state and local governments. These plans are designed to 
allow landowners to receive a federal permit to 
unintentionally harm listed species in the course of 
completing projects. In exchange for a permit, landowners 
agree to pursue specific management protections for 
threatened and endangered species. 

Hard Structures A type of bank stabilization structure incorporating rock, rip 

rap, sack concrete, gabion baskets and mattresses, or 
concrete. These structures are inert and rigid. 

Hardscape Concrete, rock, gabions, or other permanent, hard surface 

channel treatment. Refers to designs that utilize 
predominantly hard structures and are generally incapable 
of supporting vegetation (see "Softscape," "Hybrid" and bank 
stabilization table]. 

Hazard Tree The combination of a failure of a tree or part of a tree with 

the presence of an adjacent target. A hazard does not exist if 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


xx 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Headwaters 
Herbaceous Vegetation 

Herbicide 

Hybrid 


Hydraulic 


Hydrologic Basin 


Hydrology 


Hydroseed 


Impact 

Impervious Hardscape 


Implementation Measure 


there will not be an impacted target. Excluded from SMP 
coverage. 

The minor drainages in the extreme upper watershed. 

Non-woody vegetation which includes grasses, broadleaf 
weeds, cattails, bulrushes, annuals, biennials, and perennials. 

A chemical agent used to destroy or inhibit plant growth. 

For purposes of the SMP Update, refers to bank stabilization 
projects that consist of a combination of hard and softscape 
(see "Hardscape," "Softscape," and bank stabilization table]. 

Of or pertaining to the scientific or technical study of the 
static and dynamic behavior of fluids. Fluvial hydraulics is an 
engineering discipline geared toward the physics of water 
flow in channels—its volume, velocity, and elevation, in 
space and time. Hydraulic analysis is typically used to 
determine discharge capacity and to assess the effects of 
channel vegetation on channel capacity. 

For the purposes of the Stream Maintenance Program, a 
depression or valley that drains to a common waterbody. In 
Santa Clara County, there are two major hydrologic basins 
draining either into San Francisco Bay or to Monterey Bay. In 
the northern portion of the county, streams of the Santa 
Clara Basin drain to San Francisco Bay. To the south, streams 
in the Pajaro River Basin drain ultimately to Monterey Bay. 
Each basin is comprised of several watersheds. 

Hydrology is the science (or study] of water in the natural 
environment with a focus on the circulation and distribution 
of water as expressed in the hydrologic cycle or water 
balance. 

A process for revegetation of large areas. Plant seed, 
fertilizer, straw mulch, a binding agent, and green dye are 
mixed in a truck-mounted tank and sprayed through a hose 
onto the bare ground. 

See "Significant Environmental Impact." 

Paved areas such as streets and sidewalks, other developed 
areas, or bank stabilization methods which are impenetrable 
to water. 

An implementation measure is an action, procedure, 
program, or technique that carries out policy. 
Implementation measures provide specific guidance to 
District managers and staff in the environmental review and 
processing of routine stream maintenance projects. 


Santa Clara Valley Water District xxi December 2011 

Stream Maintenance Program Update 2012-2022 Project No. 10.005 

Final Subsequent Environmental Impact Report 



Glossary of Significant Terms 


Inlet 

Inoperable Canals 


Instream 

Invasive Plant 


Invasive Species 

Invert 

Lacustrine 
Lateral Branch 

Levee 


An arrangement for conveying surface water into an 
underdrain, pipe, culvert, or channel. 

Canals that were historically, but are not currently, used to 
convey water for water supply purposes. Although inoperable, 
these canals typically convey storm and non-storm runoff 
entering from upslooe locations. In general, these canals are 
unvegetated and do not support beneficial uses. However, 
pockets of wetland-associated or riparian vegetation exist in 
certain locations. Sediment removal, vegetation management, 
and bank stabilization activities in canals resulting in impacts to 
such vegetation (e.g., sediment removal that also results in 
removal of the associated vegetation) would require 
compensatory mitigation, consistent with the District’s 
mitigation program. 

For the purposes of the SMP Update, inboard levee toe to the 
opposite inboard levee toe. Where there is not a levee, 
inboard toe of the stream, ordinarily associated with 
"channel bottom" (see "bankfull bank"}. 

An invasive plant species reproduces rapidly and has the 
ability to spread aggressively outside its natural range, since 
the normal pressures of disease and predation which 
typically keep a populations growth in check are not present. 
Invasive plant species may alter ecological processes such as 
pollination patterns, nutrient cycling, fire regimes and 
modify canopy architecture causing a loss of cover, nesting 
and foraging habitat for wildlife species. Aggressive growth 
patterns often outcompete with native plant species. An 
invasive plant may be native or non-native. Non-native 
invasive plants are typically of greatest concern in native 
ecosystems. 

A subcategory of non-native plants that aggressively invades 
natural plant communities and displaces native plants or less 
aggressive weedy plants. Two examples of invasive species in 
Santa Clara County wetland and riparian areas are broad-leaf 
peppergrass (Lepidium latifolium } and giant reed (Arundo 
donax). 

The lowest point of the internal cross section of a pipe, 
culvert, or channel; the elevation of the bottom of the 
channel (see "instream"}. 

Of or pertaining to a lake. 

A secondary or subordinate branch arising from a larger limb 
or trunk (Harris et al. 2004}. 

An embankment constructed to prevent a river or stream 
from flooding adjacent lands. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XXII 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Levee Inboard 

Levee Outboard 
Levee Top 

(Toe of) Levee 
Listed Species 
Long-Term Permit 


Lower Watershed 

Maintenance Guidelines 


Marshmog 


Area of levee between inboard toe and inboard edge of levee 
top. Generally the inboard levee slope. 

Area of levee between outboard edge of levee top and 
outboard toe of levee. Generally the outboard levee slope. 

Area of levee between top of levee inboard and levee 
outboard. Generally the flat top of levees, but not necessarily 
coinciding with levee roads. 

The point on a levee slope where the designed and 
constructed levee ends and natural ground begins. 

A species that is formally designated as endangered or 
threatened by the state or federal Endangered Species Acts. 

This is a non-specific phrase for permits, authorizations, or 
memorandums of understanding from the United States 
Army Corps of Engineers, Regional Water Quality Control 
Boards, the State Water Resources Control Board, Bay 
Conservation and Development Commission, and the 
Department of Fish and Game that are for a specified period 
of time (e.g., 5 or 10 years] or an indefinite period. 

Generally, the watershed below reservoirs, including the 
main channel and outlet to the Bay. 

Engineering standards developed for each District flood 
control facility that will give guidance on maintenance 
requirements for flood control capacity. The guidelines may 
include design information, historical information, or special 
requirements for a reach of channel. 

A mechanized vegetation management vehicle with low 
ground pressure used for aquatic plant control in wetland 
and marsh areas. The Marshmog can be fitted with multiple 
attachments for mowing, cutting, discing, and applying 
herbicide. Developed by Clean Lakes, Inc. of Martinez, 
California. 


Mean Higher High Water (MHHW) The average height of the higher of the two high tides in San 

Francisco Bay. 

Mean High Water (MHW) In San Francisco Bay, there are two high tides each day, 

usually with different elevations. Mean High Water is defined 
as the average height of both of these two tides. 

Mitigation The term "mitigation" includes the following: (1] Avoiding 

environmental impacts by not taking a certain action or parts 
of an action; (2] Minimizing environmental impacts by 
limiting the degree or magnitude of the action and its 
implementation; (3] Rectifying the impact by repairing, 
rehabilitating, or restoring the impacted environment; (4] 
Reducing or eliminating the impact over time by 


Santa Clara Valley Water District xxiii December 2011 

Stream Maintenance Program Update 2012-2022 Project No. 10.005 

Final Subsequent Environmental Impact Report 



Glossary of Significant Terms 


Modified Channel 

Modifi e d Natural Chann e l 

Multi-Stem 

Natural Chann e l - 

Natural Flood Protection 

Non-Native Plant 
Non-Native Vegetation 


preservation and maintenance operations during the life of 
an action; and (5] Compensating for the environmental 
impact by replacing or providing substitute resources or 
environments (State CEQA Guidelines, CCR Title 13 Chapter 
3, Section 15370], The policies, implementation measures, 
and BMPs included in the Stream Maintenance Program have 
been designed to "mitigate" environmental impacts. The 
District Board of Directors has adopted the following 
definition, "Action taken by the District to fulfill CEQA/NEPA 
permit requirements and court-mandated mitigation to 
avoid, minimize, rectify, or reduce adverse environmental 
impacts, or to compensate for the impact(s] by replacing or 
providing substitute resources or environments." 

A waterway in which engineered alterations have occurred 
to improve the passage of flood flows or to provide drainage. 
This includes straightening (or channelization], containing a 
watercourse within constructed banks or levees, or lining 
banks with concrete, rip rap, gabions, or sack concrete. 

A wat e rcours e that has had improv e m e nts, such as bank 
prot e ction ( e .g., gabions, rip rap, oth e r r e v e tm e nts], and 
s e l e ct e d ar e as of historical chann e lization ( e .g., wid e ning, 
straight e ning] and/or oth e r capacity or passag e 
improv e m e nts. 

A tree or shrub with a root ball and multiple trunks or stems. 
This may occur at ground level or several feet above ground. 
The dbh of trees with multiple stems will be calculated by 
adding the diameters of the individual stems at 4.5 feet above 
ground. Individuals with greater than seven stems at dbh will 
be assessed by their canopy cover, per the Tree Scoring for 
Removal of Trees and Shrubs <12" DBH (April 2011], included 
with the Mitigation Approach Memo (Appendix C], 

A wat e rcours e without any significant improv e m e nts or 
modifications and v e ry littl e e vid e nc e of historical 
alterations. 

A multiple-objective approach to providing environmental 
quality, community benefit and protection from creek 
flooding in a cost effective manner through integrated 
planning and management that considers the physical, 
hydrologic, and ecologic functions and processes of streams 
within the community setting. 

A plant species that, under natural conditions, does not 
originate within the ecosystem in which it is found. 

Any vegetation that, under natural conditions, does not 
originate within the ecosystem in which it is found. These 
species may be removed by SCVWD because of their invasive 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XXIV 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Non-Iurisdictional 


Obstruction 

Ordinary High Water (OHW) 

Orographic 

Osteological 
Outfall Structure 


Palustrine 
Perennial Plant 

Pervious Hardscape 

Policy 


nature which typically reduces native vegetation cover and 
degrades natural habitat. Species include, but are not limited 
to: giant reed, tree tobacco, castor bean, pampas grass, cape 
ivy, eucalyptus and acacia. 

This term refers to USAGE jurisdiction and was not intended to 
apply to RWQCB jurisdiction, under which “waters of the state” 
typically are construed to apply to a broader set of water bodies 
than “waters of the U.S.” The District looks to the RWQCB’s 
input as to the extent and nature of jurisdiction regarding canals; 
regardless, the District believes that compensatory mitigation 
would only be necessary if maintenance activities had the 
potential to impact beneficial uses—specifically, in places where 
impacts to riparian or wetland vegetation would occur, but not in 
unvegetated areas. 

Material or objects which impede a facility from operating 
appropriately. 

In non-tidal area, the highest level of water in a channel 
reached by commonly experienced flows. Defines the limit of 
the U.S. Army Corps of Engineers jurisdiction in the San 
Francisco Bay Area as the water level reached by flood flows 
with a predicted recurrence interval of 2.33 years. 

The effect that occurs when an air mass is forced from a low 
elevation to a higher elevation as it moves over rising terrain. 
The air mass cools, its relative humidity increases, and 
clouds may form. 

Pertaining to the scientific study of bones. 

The end of a pipe or culvert that delivers local drainage into a 
creek. Features associated with an outfall structure may 
include erosion control materials, such as rip rap below the 
culvert or an energy dissipater. Further, a valve, such a flap 
gate, may also be part of the outfall structure. 

Marsh-like. 

A long-lived plant that typically has well-developed roots and 
above ground structures. May include herbaceous plants, 
vines, shrubs, and trees. 

Hardscape, such as rock rip rap, gabions, and cellular soil 
confinement, which is not a barrier to water infiltration and 
that may allow (limited] revegetation growth. 

Policies guide decision-making, both for individual stream 
maintenance projects and for the implementation of other 
related programs and projects. Policies are commitments 
made by the District Board of Directors. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


xxv 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Post-Emergent Herbicide 

Pre-Emergent Herbicide 

Preventive Maintenance (PM) 

Program 

Project Area 

Protocols 

Reach 

Recharge 

Regrowth 

Repair 

Residual Impact 

Restoration 


A herbicide designed to control target plant material after it 
has emerged. Post-emergents control plants by disrupting 
various growth mechanisms. 

A herbicide designed to control target plant material prior to 
germination. Pre-emergents are applied to the soil surface, 
watered in through rainfall or artificial irrigation, and 
prevent germination and growth of seeds in the upper soil 
strata. 

Preventative maintenance describes a group of work 
activities that are generated on a set schedule (most often 
annual or biannual) automatically for regularly scheduled 
work. Because of the type of work and location, these 
assigned work order codes will not need to be authorized by 
an environmental planner but will be required to follow SMP 
BMPs, including biological preconstruction authorizations. 

A program is a series of actions that can be described at a 
general level of detail. Programs include agency plans, 
policies, or regulatory programs. 

The area within the District that is subject to routine 
maintenance. This area contains 522.8 miles of creek 
channels. 

An established set of ground rules or procedures governing 
routine stream maintenance activities. 

The smallest subdivision of a drainage system consisting of a 
uniform length of channel or a discrete portion of a channel. 

The replenishment of groundwater aquifers by infiltration. 

The growth of vegetation subsequent to disruptive activities, 
such as sediment removal that originally removed all 
vegetation within the work or study area. 

For the purposes of the Stream Maintenance Program, repair 
refers to maintenance of bank stabilization structure with in- 
kind, in-place materials. This type of maintenance occurs 
when such structures fail. 

Significant environmental impacts that cannot be avoided 
through the implementation of feasible site-specific 
measures. Significant residual impacts can be offset through 
a provision of compensatory mitigation. 

The reestablishment of the structure and function of 
ecosystems. Ecological restoration is the process of returning 
an ecosystem as closely as possible to pre-disturbance 
conditions and functions. Implicit in this definition is that 
ecosystems are naturally dynamic. It is therefore not possible 
to recreate a system exactly. The restoration process 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XXVI 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


reestablishes the general structure, function, and dynamic 
but self-sustaining behavior of the ecosystem. The District 
Board of Directors has adopted the following definition, 
"Action taken by the District, to the extent practicable, 
toward the re-establishment of an ecosystem's pre¬ 
disturbance structure, function, and value, where it has been 
degraded, damaged, or otherwise destroyed." 

A term used to describe any number of hard structures used 
in bank stabilization. 

Loose rock or concrete of varying size, typically brought to a 
site. Used to protect channel banks from scouring forces. 

Located along the edge of a channel, generally on the 
floodplain. Characterized by access to and influence of the 
channel, but not in it. A riparian zone or riparian area is the 
interface between land and a river or stream. Riparian is also 
the proper nomenclature for one of the fifteen terrestrial 
biomes of the earth. 

Riparian Corridors Refers to a biological zone dominated by riparian vegetation 

immediately next to a channel. See "Riparian Vegetation." 

Riparian Vegetation (or Habitat) Riparian habitat is composed of the trees and other 

vegetation and physical features normally found on the 
stream banks and flood plains associated with streams, lakes, 
or other bodies of water. 

(http: / / www. web .ca.gov/Riparian/) 

Riverine Of, related to, or growing in rivers and streams. 

Rootwad A tree stump (dead or alive) with roots. May be used in place 

of hard structures during restoration activities. 

Rotational Slump Where a layer of permeable rock (absorbs water) in a cliff 

face sits upon a layer of impermeable rock(doesn't absorb 
water). When it rains, water soaks through the layer of 
permeable rock, but doesn't through the impermeable rock. 

A layer of water collects until the top layer of rock slips. The 
layer collapses down the front of the cliff face in a rotational 
manner. 

Routine Stream Maintenance Routine stream maintenance includes four major activities, 

as follows: (1) sediment removal activities that are designed 
to restore the flood capacity of existing District channels or 
associated features (e.g., tide gates), (2) vegetation 
management in and around the District's channels, including 
removal of vegetation for access and fire control, (3) bank 
stabilization activities necessary to protect District or other 
facilities, and (4) management of animal conflicts. Routine 
stream maintenance also includes more minor maintenance 
activities, such as trash removal; fence work; access road 


Revetment 

Riprap 

Riparian 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XXVII 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


maintenance; repair of structures with in-kind materials 
within the same footprint (such as replacement of concrete 
linings, culverts, pipes, valves, or similar structures]; 
cleaning and minor sediment removal at stream gages, 
outfalls, flap gates, tide gates, fish ladders; and graffiti 
removal. 

For the purposes of the Stream Maintenance Program, a project 
is the whole of a routine stream maintenance action that is 
proposed for implementation through the Stream Maintenance 
Program. A project has a specific location, duration, and 
purpose. (An example of an individual project would be the 
removal of 3,000 cubic yards of sediment from Adobe Creek 
between Highway 101 and East Charleston Road.] Major 
construction and repair, including CIPs, are not defined as 
routine stream maintenance projects. In the Stream 
Maintenance Program, also referred to as "individual stream 
maintenance project," "individual project,” "stream 
maintenance project," and "project." 

Ruderal Vegetation containing mostly introduced, weedy herbaceous 

species; "disturbance loving" species. Common in disturbed 
areas, along roadsides or vacant lots. 

Runoff (surface) The flow of water across the land surface and in stream 

channels. Occurs only after the local storage capacity of the 
landscape has been exceeded and includes both overland 
flow and streamflow. 

Scour The clearing and digging action of flowing air or water, 

especially the downward erosion caused by steam water in 
removing material (e.g., soil, rocks] from a channel bed or 
bank or around in-channel structures. 

Secondary Channel For purposes of the SMP, secondary channels are constructed 

features of a main channel that are designed with flood 
conveyance or maintenance purposes. These channels often 
have maintenance requirements that are different than the 
main channel and are therefore specifically managed and 
reported separate from the main channel. 

Section 404 Refers to a section of the Clean Water Act establishing a 

permit program for the discharge of dredged or fill materials 
into Waters of the United States. 

Sediment Particles derived from rocks or biological materials that have 

been transported by a fluid, or solid material suspended in or 
settled from water. 

Sediment Basin A depression formed by the construction of a barrier or dam 

built at a suitable location to retain rock, sand, gravel, silt, or 


Santa Clara Valley Water District xxviii December 2011 

Stream Maintenance Program Update 2012-2022 Project No. 10.005 

Final Subsequent Environmental Impact Report 


Routine Stream Maintenance 
Project 



Glossary of Significant Terms 


other material. In SCVWD, these basins also are commonly 
called “Debris Basins." 

Sediment Load The sediment that is in transport. Load is a general term that 

refers to material in suspension and/or transport. It is not 
synonymous with discharge. 

Sediment Removal The act of removing sediment deposited within a stream. 

Typically, sediment is removed when it reduces capacity. 

This is the sediment removal activity referred to most often 
in the Stream Maintenance Program, and included in the 
program-level impact analysis. There is a subset of sediment 
removal that is conducted for purposes of allowing 
appurtenant structures (stream gages, outfalls, diversion 
sills, flap gates, and tide gates] to continue functioning, and 
to clear fish passage and access to fish ladders and weirs. 

This latter category of sediment removal is considered 
"minor maintenance," as described in Chapter 3 of the 
Stream Maintenance Program. 

Sensitive Habitat A general term used to characterize habitats that either 

support sensitive species (listed species, species proposed 
for listing, and species of special concern] or are designated 
as a sensitive natural community in local or regional plans, 
policies, regulations, or by the CDFG or the U.S. Fish and 
Wildlife Service. 

Sensitive Species A general term for listed (i.e., on a state or federal 

endangered species list] species, species proposed for listing, 
and species of special concern (other species that may be of 
concern to state or federal agencies]. 

Serpentine Soil/Habitat A serpentine soil is derived from ultramafic rocks, in 

particular serpentinite, a rock formed by the hydration and 
metamorphic transformation of ultramafic rock from the 
Earth's mantle. Soils derived from serpentine are toxic to 
many plants, because of high levels of nickel, chromium, and 
cobalt; growth of many plants is also inhibited by low levels 
of potassium and phosphorus and a low ratio of 
calcium/magnesium. The flora is generally very distinctive, 
with specialized, slow-growing species. Areas of serpentine- 
derived soil will show as strips of shrubland and open, 
scattered small trees (often conifers] within otherwise 
forested areas. As a result, serpentine habitat is typically host 
to a number of unique or rare plant species. 

The aquatic area occurring along the edge of a channel 
where the adjacent bank is composed of natural materials 
and supports riparian vegetation that overhangs or 
protrudes into the water and provides fish and other 
aquatic habitat. 


Shaded Riverine Aquatic Habitat 
(SRA) 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XXIX 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Shear Stress The force tending to cause deformation of a material by 

slippage along a plane or planes parallel to the imposed 
stress. 

Shrub Woody plant smaller in height than a tree (less than 

approximately 16 feet [5 meters] at maturity], often formed 
by a number of vertical or semi-upright branches arising 
close to the ground. 

Significant Environmental Impact A significant environmental impact is a substantial, or 

potentially substantial, adverse change in any of the physical 
conditions within the area affected by a project, including 
land, air, water, minerals, flora, fauna, ambient noise, and 
objects of historic or aesthetic significance (State CEQA 
Guidelines, CCR Title 13 Chapter 3, Sections 15358 and 
15382], 

Significant Rainfall Local rainfall 0.5 inches or greater within a 24-hour period in 

the subject watershed. 

Soft Structures A type of bank stabilization structure incorporating 

biological materials, such as seeds, plants, plant parts (e.g., 
root wads], or a combination of vegetation and inert 
materials (e.g., brush mats/sills, wattles, fascines, or branch 
packing/layering]. 

Softscape Earth channel or levees, either natural or modified. Also 

refers to "soft forms of bank stabilization” such as root wads, 
log structures, etc. (see "hardscape,” "hybrid," and bank 
stabilization table. 

Sphere of Influence (SOI) A formally designated area of unincorporated land adjoining 

a city that is considered to be in the city's (jurisdiction] 
sphere of influence for land planning based on geographic, 
economic, and social factors. The SOI is set by the State Local 
Agency Formation Commission (LAFCo] for each county. 

Gravel berm placed across the channel to retain water in 
reaches of high channel permeability to improve ground 
water recharge. 

A stakeholder is an individual or organization who will be 
affected by or has an interest in the Stream Maintenance 
Program. Stakeholders include regulatory agency 
representatives, municipalities, and environmental and 
business groups. 

Station is a standard channel location system used by the 
District, which gives the distance from the downstream limit 
of jurisdiction (usually San Francisco Bay], or, for a tributary 
creek, from where it branches off of the main channel. 
Distance is measured in feet, with each "station" 
representing 100 feet. For example, station 43+56 would be 


Spreader Dam 


Stakeholder 


Station 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


xxx 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Stewardship 

Stream 


Stream Maintenance Program 


Stream Maintenance Program 
Project Area 


Streambed 
Sudden Oak Death 


Surfactants 


a point 4,356 feet upstream from the mouth of the channel. 
Stations are used to define reaches (e.g., "From Station X - To 
Station Y"). 

To entrust the careful and responsible management of the 
environment and natural resources to one's care for the 
benefit of the greater community. 

For the purposes of the Stream Maintenance Program, 
"streams" are defined as the natural watercourses and 
modified channels and canals within the District's 
jurisdiction. In this Program, streams include both the 
waterway and its immediate geographical corridor, including 
riparian corridors. 

The Stream Maintenance Program (SMP] will provide long¬ 
term guidance to the District to effectively implement 
routine stream maintenance projects in a cost-effective and 
environmentally sensitive manner. The Stream Maintenance 
Program is to be codified in a process and policy document 
that can be adopted by the District and utilized in obtaining 
long-term permits from regulatory agencies. The Stream 
Maintenance Program includes specific measures, protocols, 
and monitoring and reporting requirements to ensure that 
routine stream maintenance projects are implemented in an 
effective, cost-sensitive, and environmentally sensitive 
manner. 

The SMP project area includes streams and any adjacent 
property that the District owns or holds an easement for 
access and maintenance. The District does not provide 
maintenance on private property when no easement exists. 
Other than leveed creeks (which can require a wider 
maintenance easement], the maintenance work area is 
within approximately 20 feet of the top of bank when 
access is provided, and can be substantially less when 
access is not provided. 

The part of a stream over which a column of water moves. 

Sudden Oak Death is the common name of a disease caused 
by the oomycete plant pathogen Phytophthora ramorum. The 
disease kills oak and other species of tree and has had 
devastating effects on the oak populations in California and 
Oregon. 

A shorthand term for surface-active agent, which are 
chemicals that modify surfaces of two liquids or a liquid and 
a solid. In the context of the Stream Maintenance Program, 
surfactants are used in combination with herbicides to 
increase the retention and penetration of herbicides on and 
into plants. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XXXI 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Suspended Sediment 

Take (of a Listed Species) 

Thalweg 

Tree 

Trimming 

Turbidity 

Unavoidable Impact 


Unmodified Stream 


Fine particles suspended in the water column and carried 
along with the water at the velocity of flow. Compare with 
"Bedload." 

To harass, harm, pursue, hunt, shoot, wound, kill, trap, 
capture, or collect a listed species or its habitat, or to attempt 
to engage in any such activity. 

Main channel in the creek. 

A species of woody perennial that typically has one dominant 
vertical trunk and a height greater than approximately 16 
feet (5 meters) in its natural form. Tree species may have 
multiple trunks or be less than approximately 16 feet (5 
meters) at maturity. 

The systematic removal of branches of a plant, usually a 
woody perennial (Harris 2004). Synonym for pruning. 

The pollution of water by dissolved or suspended solids. The 
cloudiness of water, caused by suspended sediment. 
Turbidity is measured by the degree to which light 
penetration is blocked because the water is muddy or cloudy. 

An unavoidable impact would occur if specific economic, 
social, legal, technical, or other considerations make 
mitigation measures or alternatives for the impact of a 
project infeasible. When such impacts are considered 
"significant," to support its decision on a project for which an 
EIR was prepared, a Lead Agency must prepare written 
findings the identify that either: (1) changes to the project 
are within another agency's jurisdiction and have been or 
should be adopted, (2) specific economic, social, legal, 
technical, or other considerations make mitigation measures 
or alternatives infeasible (State CEQA Guidelines Section 
15091). In addition, the Lead Agency must adopt a Statement 
of Overriding Considerations which describes how the 
benefits of the project outweigh the unavoidable adverse 
environmental effects (State CEQA Guidelines Section 15092, 
15096(h)). 

An unmodified stream is defined for the purposes of the SMP 
as a creek, river, or section thereof, which has not undergone 
the process of construction of modifications to meet specific 
flood control criteria. Examples of such criteria would 
include design to pass specific flows, such as a 25-year flood; 
or the protection of a specific number of homes, businesses, 
schools, etc. All unmodified streams will be assessed for flow 
conveyance in relation to their function within the 
watershed. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


XXXII 


December 2011 
Project No. 10.005 



Glossary of Significant Terms 


Unrevetted Without revetment (i.e., a bare slope or channel side without 

hardscape protection]. 

Unvegetated _ Areas containing either no. or only ruderal. vegetation. Examples 

would be locations that are concrete, or that support primarily 
annual non-native grasses and forbs. These areas provide little to 
no habitat value and, as such, maintenance activities in these 
locations would not have impacts requiring compensatory 
mitigation, 

Upland _ Terrestrial, referring to habitats that are not wetland or 

aquatic habitats. 

Upper Watershed Generally, the steeper portion of a watershed, above 

reservoirs and above urban areas. 

Vegetation Management/Removal Removal of vegetation in and adjacent to creeks to maintain 

the ability of channels to function as flood control facilities. 

In addition, vegetation is removed to meet local fire code 
requirements and to reduce combustible weeds and grasses 
on property adjacent to the streams within the District's 
jurisdiction. The control of invasive non-native vegetation is 
another purpose for which the District undertakes vegetation 
control. Vegetation management can be accomplished 
through mowing, discing, hand pruning, hand removal, or 
herbicide applications (depending on the environmental 
conditions of the site]. 

Waste Discharge Requirement A legal mechanism of the state and regional Water Quality 

Control Boards to regulate discharges of dredge or fill 
materials. 

Waters of the United States Waters of the United States are tidal waters, all interstate 

waters, including wetlands, and all other waters which could 
involve interstate or foreign commerce. 

Watershed Entire area that drains to a common stream, synonymous 

with drainage area. A ridge or drainage divide separates a 
watershed from adjacent watersheds. For purposes of the 
SMP Update, watershed means the five SCVWD 
administrative watersheds: Lower Peninsula, West Valley, 
Guadalupe, Coyote, and Pajaro. 

Wetlands Those areas that are inundated or saturated by surface or 

groundwater at a frequency and duration sufficient to 
support, and that under normal circumstances do support, a 
prevalence of vegetation typically adapted for life in 
saturated soil conditions. Wetland is characterized by having 
the appropriate plant species (dependant on or capable of 
surviving root saturation], the appropriate hydrology 
(predictable saturation], and soils reflecting saturation and 
periodic anaerobic conditions. 


Santa Clara Valley Water District xxxiii December 2011 

Stream Maintenance Program Update 2012-2022 Project No. 10.005 

Final Subsequent Environmental Impact Report 



Glossary of Significant Terms 


Winterization 


Woody Vegetation 


Work Sites 


Winterization is the process to maintain project sites with 
the appropriate BMPs to prevent erosion, sediment 
transport, and protect water quality. Winterization occurs 
upon completion of bank repairs or on incomplete projects 
after October 15 and prior to the forecast of significant 
rainfall, 0.5 inches or greater of rainfall within 24 hours in 
the subject watershed. Winterization shall be completed 
prior to the occurrence of such actual significant rainfall. 
Winterization materials will be available and on-site when 
rain falls after October 15. 

Winterization includes erosion control practices, sediment 
control practices, and general site and materials 
management. 

• Basic ground rules for winterization: 

1. Direct runoff away from disturbed areas. 

2. Retain existing vegetation as much as possible. 

3. Fit grading to the surrounding terrain. 

4. Prepare temporary drainages and outlets. 

5. Grade/excavate outside of rainy season. 

6. Minimize length and steepness of slope. 

7. Stabilize disturbed areas by mulching, vegetating 
(hydromulching, hydroseeding, hydraulic matrices, 
blankets, etc.]. 

8. Use every dissipating measure to keep runoff 
velocities low. 

9. Trap sediment on site. 

10. Inspect, log, and maintain control measures after 
each storm. 

• BMPs may include use of: 

1. Silt fences 

2. Straw bales 

3. Straw wattles/fiber rolls 

4. Erosion control blankets, plastic sheeting 

5. Drain protection structures/drain fdters 

6. Sediment basins 

7. Stabilized entrances/exits (incl. tire wash] 

• Proper use of erosion and sediment control BMPs 
requires training by experienced professionals. 
Certifications are available through the IECA 
(International Erosion Control Association]. 

Live vegetation having a stiff trunk or branch structure that 
is inflexible and does not bend over in flows. Typical 
vegetation types include trees and large shrubs. 

The locations where maintenance activities are anticipated 
to occur. For the SMP Update, such locations have been 
identified for the 2012-2022 time frame. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


xxxiv 


December 2011 
Project No. 10.005 



Executive Summary 


Introduction 

The Santa Clara Valley Water District (SCVWD] has developed the Stream Maintenance 
Program (SMP} Update to review existing SMP activities, revise the SMP Manual, update the 
SMP's environmental compliance documentation, and renew necessary SMP permits. The 
SMP Update is considered a “project" for the purposes of the California Environmental 
Quality Act (CEQA] and is referred to as the “Proposed Project" or "SMP Update" throughout 
this document. 

SCVWD has prepared this draft subsequent environmental impact report (DSEIR] to 
provide the public, responsible agencies, and trustee agencies with information about the 
potential environmental effects of implementation of the Proposed Project. This DSEIR was 
prepared in compliance with CEQA (Public Resources Code Section 21000 et seq.] and the 
State CEQA Guidelines (14 California Code of Regulations [CCR] 15000 et seq.}. SCVWD is 
the lead agency on the Proposed Project. 

Proposed Project Overview 

The SMP Update has been prepared to provide guiding policies, specific direction on 
approach, and regulatory authorization for routine stream and canal maintenance activities. 
The Proposed Project would update the 2002 SMP, as necessary, to meet new conditions or 
maintenance needs of SCVWD. The SMP Update (including the 2012 SMP Manual 
[Appendix A] and this CEQA document] is an ongoing and continuous program with an 
indefinite time horizon; int e nd e d to cov e r th ea 10-year planning period beginning in 2012 
and ending in 2022 has been used for the purposes of the regulatory permitting . These SMP 
Update documents are intended to fully replace the original documents that guided the SMP 
from its inception through 2012. The 2012 SMP Manual (included as Appendix A in this 
DSEIR] and the contents of the DSEIR are meant to be read as companion volumes. The 
DSEIR references or summarizes information (including figures and tables] presented in the 
2012 SMP Manual frequently to avoid repeating information. The reader is encouraged to 
review the 2012 SMP Manual while reviewing the DSEIR. 

Proposed Project Objectives 

The overall flood management goals of the SMP Update are to maintain the design flow or 
appropriate conveyance capacity of SCVWD facilities, and to maintain the structural and 
functional integrity of SCVWD facilities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-1 


December 2011 
Project No. 10.005 



Executive Summary 


To meet these goals, the SMP Update would prioritize and administer maintenance 
activities to achieve the following objectives: 

■ remove sediment to maintain the hydraulic, safety, and habitat functions of the 
creek systems; 

■ manage vegetation to maintain the hydraulic, safety, and habitat functions of the 
creek systems, and to allow for levee inspections and maintenance access; 

■ stabilize beds and banks of creeks and canals to protect existing infrastructure, 
maintain public safety, reduce sediment loading, protect water quality, and protect 
habitat values; and 

■ avoid, minimize, or mitigate impacts on the environment by incorporating stream 
stewardship measures into maintenance activities. 

The SMP Update also seeks to obtain and maintain multi-year programmatic permits to 
regulate Proposed Project activities. 

Proposed Project Background 

SCVWD is responsible for water supply, flood protection, and stream stewardship in Santa 
Clara County, California. SCVWD flood protection facilities require maintenance to maintain 
the designed function of each facility. Historically, SCVWD has implemented these activities 
as needed. Therefore, the SMP Update would be a continuation of past routine creek and 
canal maintenance activities in most of the same areas using many of the same techniques. 
The difference between stream maintenance conducted before the SMP (pre 2002] and the 
initial SMP period (2002-2012] is the SMP Update's comprehensive approach to managing 
and tracking the maintenance work and costs, monitoring environmental conditions, and 
providing program mitigation. The SMP Update would be used by SCVWD staff to conduct 
routine stream maintenance practices in an efficient, consistent, and environmentally- 
sensitive manner. 

The requirements and policies of the original SMP document were finalized in 2002, when 
SCVWD completed CEQA review requirements and received authorizations from all the 
permitting agencies with jurisdiction over the program. Work under the existing SMP began 
in 2002. 

Project Area 

The Project Area includes the portions of Santa Clara County below the 1,000-foot elevation 
contour, as shown in Figure ES-1. The Project Area includes streams within the Santa Clara 
and Pajaro basins. Municipalities within the Project Area that contain SCVWD-owned or 
maintained channels include the cities of Campbell, Cupertino, Gilroy, Los Altos, Milpitas, 
Morgan Hill, Monte Sereno, Mountain View, Palo Alto, San Jose, Santa Clara, Saratoga, and 
Sunnyvale, and the towns of Los Altos Hills and Los Gatos. SCVWD does not provide 
maintenance on private property where no easement exists, unless expressly authorized by 
the SCVWD Board of Directors. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-2 


December 2011 
Project No. 10.005 



s:/2010/Horizon/SCVWD/GIS/Layouts/Fig1 ProjectArea.mxd (05.16.11) mg 



t Horizon 

twu .•iivrtoMfivr 


Figure ES-1: Project Area 


















































Executive Summary 


This page intentionally left blank. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-4 


December 2011 
Project No. 10.005 



Executive Summary 


Proposed Project Channel Types 

SCVWD actively manages over 1,000 miles of channels and creeks. For purposes of this 
document, the channels within SCVWD's jurisdiction are classified as earthen, concrete, 
tunnel, siphon, pipeline, or waterbody. The majority of SMP channels are earthen, having 
earthen channel bed and banks. SCVWD-maintained earthen channels may be either 
engineered or natural stream channels. 

The SMP Update would not cover maintenance activities at reservoirs, dams, pipelines 
outside of stream corridors, groundwater percolation facilities, in-stream summer dams, or 
work in stream reaches above the 1,000-foot elevation contour. 

Proposed Project Description 

Overview of SMP Update Approach 

Based on the work performed during the SMP 2002-2009, SCVWD has developed 
projections for reasonably anticipated work expected to occur over the next decade of the 
Proposed Project (2012-2022], Actual stream maintenance activities vary from year to 
year, depending on weather and hydrologic conditions, frequency and extent of past 
maintenance activities, and budget/funding availability. Future maintenance needs may 
occur, consistent with the overall SMP Update projections, but they may vary from the 
specific location originally projected. 

Maintenance activities would be permitted throughout the Project Area, as long as they did 
not result in new or more significant environmental effects than those evaluated and 
disclosed in this DSEIR. The 2012-2022 maintenance work projections represent the 
District's best estimate of where work is likely to occur. The work projections are 
"conservative" in that work is not likely to occur in all of the newly identified reaches shown 
on the maps presented in Chapter 2. The work projections are a useful basis to consider 
potential programmatic impacts to wetlands and other habitats and, therefore, to develop a 
suitable mitigation approach that can guide the next decade of the program. 

The SMP Update has been designed to be adaptable. One way the SMP Update would 
achieve this would be by supporting site-specific assessments to determine the most 
effective method to achieve the maintenance goal. As conditions allow and technologies and 
environmental regulations evolve, this would support an assessment for work activity 
modifications that could result in decreased impacts. 

Maintenance Activities 

The SMP Update would involve five categories of work activities: bank stabilization, 
sediment removal, vegetation management, management of animal conflicts, and minor 
maintenance. In addition, the SMP Update would include maintenance of canals, which may 
include any of these five activities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-5 


December 2011 
Project No. 10.005 



Executive Summary 


Bank Stabilization 

Stream bank stabilization activities would involve actions by SCVWD to repair eroding 
stream banks and levees. SCVWD may implement stream bank stabilization activities when 
the problem: causes or could cause significant damage to SCVWD property and/or adjacent 
property; or is a public safety concern. Additional benefits of stabilizing eroding stream 
banks include reducing instream sedimentation, and protecting water quality and other 
beneficial uses such as riparian habitat and recreation. 

Bank stabilization work could be performed along any creek or canal where SCVWD has fee 
title or easement, or was otherwise directed by the SCVWD Board of Directors. Based on the 
maintenance work conducted from 2002-2010, the District stabilizes about 0.94 mile of 
stream channel banks or levees on average per year. The 2012 SMP Manual (Appendix A] 
describes the specific bank stabilization techniques and approaches. SCVWD favors the use 
of soft bank stabilization approaches that use bio-technological approaches in place of 
methods that create more hardened banks. 

Sediment Removal 

Sediment removal is the act of mechanically removing sediment deposited within a flood 
protection channel. Sediment removal is required when accumulated sediment reduces a 
channel's flow conveyance capacity, prevents facilities or appurtenant structures from 
functioning as intended, or impedes fish passage and access to fish ladders. Sediment is 
removed from SCVWD facilities to allow channels to convey flow and minimize flood 
hazard, according to the original channel design. Sediment removal under the SMP Update 
would not include increasing a channel’s flow conveyance capacity beyond the as-built 
design. Sediment removal activities may occur along creeks, canals, or at stream gauges. 

Sediment removed from SCVWD channels and facilities would be assessed according to the 
appropriate Sediment Characterization Plan established by the San Francisco Bay and 
Central Coast Regional Water Quality Control Boards. These characterization plans would 
be used to determine the physical and chemical properties of the removed sediment, using 
continuous core, discrete sampling and residual sampling methods. Collected sediment that 
met wetland reuse criteria could be transferred to the South San Francisco Bay Pond A8 to 
support levee restoration efforts at the pond. Sediment that did not meet these standards 
but met standards for landfill disposal would be disposed at a local landfill. Sediment that 
exceeded hazardous waste criteria would be disposed at an appropriate hazardous waste 
facility (e.g., Kettleman Hills hazardous waste landfill]. Pond A8 is anticipated to have 
sufficient capacity for sediment disposal for the next 2-5 years. Additional ponds, including 
ponds A5, Al, A2W, and A9 have been identified as other potentially suitable long-term 
sediment reuse locations. SCVWD also may add other upland or aquatic sites to its disposal 
options. Potential upland sites include the abandoned quarry pond next to the Coyote 
Parkway site, as well as the U.S. Fish and Wildlife Service refuge at Bair Island and Phase 2 
of the South Bay Salt Pond restoration effort. 

Annual sediment removal needs would vary, depending on yearly climate and hydrologic 
conditions. Sediment removal could be performed in any stream within the Project Area. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-6 


December 2011 
Project No. 10.005 



Executive Summary 


Vegetation Management 

Similar to sediment removal activities, vegetation management activities are intended to 
maintain the hydraulic conveyance and flood safety functions of SCVWD's channels. 
Vegetation maintenance would seek to trim, thin, or remove vegetation that was causing 
flow blockages or significantly increasing hydraulic roughness and, thereby, reducing 
channel conveyance capacity. Vegetation management methods would include pruning, 
hand or mechanical removal, herbicide application, mowing, discing, flaming, and grazing. 

SCVWD's preference is to first thin or prune trees before considering tree removal. 
However, when tree removal is necessary, SCVWD prioritizes retaining native trees in place 
of non-native species. The removal of trees and shrubs less than or equal to 12 inches 
diameter at breast height (dbh] is permissible only if they are required for bank 
stabilization projects, ecological health/stewardship purposes, or to maintain flow 
conveyance. As defined in the projections (Chapter 2, Project Description, or Appendix A, 
2012 SMP Manual], vegetation management may occur from the creek center to the outer 
edge of the SCVWD property line/SCVWD management area. Other types of vegetation 
management (e.g., flaming and grazing] would be performed on an as-needed basis along 
any creek within the Project Area where SCVWD has fee title or easement. Tree removals 
may occur on a site-specific basis, per the criteria and mitigation described in the SMP 
Manual. 

Management of Animal Conflicts 

In the Project Area, animals can damage SCVWD channels, facilities, and infrastructure. The 
stability of banks and levees may be reduced as a result of burrowing, foraging on 
mitigation sites, and interfering with work activities. Management of animal conflicts refers 
to the use of avoidance tactics, biological control, site alterations, habitat alteration, and 
lethal control to reduce conflicts between SCVWD facilities and local species. These control 
methods are described in the Management of Animal Conflicts chapter of the 2012 SMP 
Manual (Appendix A], 

Although routine, the extent and specific locations for animal conflicts management are 
generally not known before the maintenance season; although routine rodent control 
activities would occur on designated levee reaches. 

Minor Maintenance 

Minor maintenance activities would be performed to repair and maintain SCVWD facility 
functions. Minor maintenance activities may occur along creeks, canals, or at existing 
stream gauges. Minor maintenance activities would have limited potential to impact 
environmental resources. A minor activity is defined as an activity that results in removing 
less than 0.05 acres (2,178 square feet] of wetland or riparian vegetation. The minimum 
reporting size for any minor vegetation work to be notified in SCVWD's Notice of Proposed 
Work would be 0.01 acres (436 square feet] per project, which would include any 
vegetation work necessary for access or staging. Minor maintenance activities may occur 
anywhere within the Project Area. 

Minor maintenance activities proposed under the SMP Update would include: 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-7 


December 2011 
Project No. 10.005 



Executive Summary 


■ cleaning and minor sediment removal at outfalls, culverts, flap gates, tide gates, 
inlets, grade control structures, fish ladders, fish screens (limited to 50 cubic yards 

[cy]); 

■ minor in-channel (or canal] sediment removal (less than 10 cy]; 

■ trash and debris removal; 

■ repair and installation of fences and gates; 

■ grading and other repairs to restore the original contour of existing maintenance 
roads; 

■ grading small areas without vegetation above stream banks to improve drainage 
and reduce erosion; 

■ repair of structures with substantially similar materials within approximately the 
same footprint (i.e., replacement of concrete linings, culverts, pipes, valves]; 

■ graffiti removal; 

■ installation and on-going maintenance of mitigation and landscape sites (including 
irrigation, weed control, and replanting of dead or declining individual plants until 
success criteria were met]; 

■ removal of obstructions at structures to maintain function (i.e., bridges, stream flow 
measuring stations, box culverts, storm drain outfalls and drop structures]; and 

■ stream gauge maintenance including stilling well cleaning, painting of gauge house, 
replacing/adding antenna or solar panels to existing structures, replacing 
instrumentation, cableway repair, weir cleaning of algae and debris, and unburying 
staff markers/orifice/communication pipes. 

Canal Maintenance 

The SMP Update would include routine and periodic maintenance conducted by SCVWD on 
its canals. Unlike the streams and flood protection channels that are the primary focus of 
the existing SMP, SCVWD's canals are primarily water supply transport facilities and may 
provide incidental flood protection. Routine canal maintenance may include all general 
work activities discussed above, including sediment removal, vegetation management, 
management of animal conflicts, bank stabilization, and minor maintenance. 

Sediment removal in canals is typically small in scale and localized (generally 10 cy or less 
per occurrence], and is conducted to clear small sediment deposits (“plugs"] where local 
sediments have either entered the canal or been deposited. Sediment removal may occur 
anywhere along the canals, however no more than 1,000 cy of sediment would be removed 
per calendar year from all SCVWD canals. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-8 


December 2011 
Project No. 10.005 




Executive Summary 


Vegetation management along the canals would include some periodic herbicide use, inside 
the canals and along the access roads, to address weed growth. In the upland margins 
adjacent to the canals, SCVWD would conduct periodic and routine tree hand pruning, hand 
removal, and grass mowing, using the same techniques described above in the Vegetation 
Management section. In general, vegetation management may occur anywhere along or 
within the canals; however, no more than 6 acres of work would be performed in a given 
calendar year. In addition, discing would be restricted to the right bank of Coyote Alamitos 
canal only. 

Additional minor maintenance activities performed along the canals would include minor 
grading of the access road, graffiti removal, fence repair, erosion repairs, management of 
animal conflicts, and bank stabilization activities. Minor structural repairs may include 
repairing a concrete lining, culvert, pipe, valve, weir, instream orifice, or communication 
pipe. These canal maintenance activities may occur anywhere along the canals, as needed. 

Activities Not Covered in the SMP Update 

The SMP Update would not include the following activities, which are therefore not 
analyzed in this DSEIR: 

■ work that would increase the designed flood conveyance or water supply capacity of 
a facility; 

■ maintenance work in stream reaches above the 1,000-foot elevation contour; 

■ removal of hazard trees; 

■ maintenance work for dams, reservoirs and other water supply facilities, such as 
pipelines outside of stream corridors, groundwater percolation ponds, and in- 
stream summer dams; 

■ installation of new or major modification of fish ladders; 

■ work conducted on private property by others; 

■ work performed by other agencies; 

■ other large construction projects or capital improvement projects; 

■ area-wide, intensive maintenance, or rehabilitation of large (greater than 0.05 acre] 
mitigation projects installed as part of SCVWD Capital Improvement Projects; 

■ emergency repair work; and 

■ continued implementation of mitigation measures in the existing SMP. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-9 


December 2011 
Project No. 10.005 




Executive Summary 


Stream Maintenance Process Overview 

Annual administration of the SMP Update would occur in three phases, as described in 
detail below. 

Phase 1: Annual Maintenance Activity Identification, Development and 
Documentation 

The first phase of the annual work sequence would begin with identifying maintenance 
needs. Maintenance work could be proposed either as part of the annual work plan through 
the Notice of Proposed Work, subsequent regulatory notifications/submittals, or as 
identified throughout the year via individual work orders. SCVWD internal work orders 
would provide a description of the project, schedule of implementation, estimated costs, 
permit requirements, and other special conditions. 

For minor maintenance activities, the appropriate resource protection measures and BMPs 
would be identified and work would proceed. For other maintenance activities, a more 
detailed review process would occur and may include site assessment and/or engineering 
evaluations. These activities would be reviewed to verify they were covered under the long¬ 
term regulatory clearances provided in conjunction with the SMP Update. If the work was 
not covered by the SMP Update, the appropriate project development process would be 
followed and may include individual CEQA review and project-specific regulatory permits 
or clearances. For covered activities, appropriate resource protection measures and BMPs 
would be identified and added to the work order. Pre-work meetings would be held with 
appropriate SCVWD staff to discuss site-specific requirements, environmental constraints, 
and BMPs. 

Phase 2: Implementation of Annual Routine Stream Maintenance Work 

Maintenance activities would be implemented during the appropriate work season or as 
described in the work order. In addition, direct field monitoring of maintenance work 
would occur for both sediment removal and bank repair activities, enforcing BMPs to 
effectively prevent adverse impacts to water quality and stream habitats. 

Maintenance Timing 

Work windows for sediment removal, in-stream vegetation and herbicide application, and 
bank stabilization generally would be conducted between June 15 and October 15. 
However, if the fall season remained dry, work could continue until the first significant 
rainfall event occurred. Sediment removal may occur after a significant rainfall under 
special circumstances but only in low quality areas. A significant rainfall event is defined as 
local rainfall of 0.5 inches or greater within the watershed over a 24-hour period. Even if no 
significant rainfall occurred, no instream work (excluding hand pruning and hand removal 
in non-steelhead streams] would continue later than December 31. 

After October 15, 72-hour look-ahead weather forecasts from the National Weather Service 
(or local vendor such as the Western Weather Group] would be consulted. If a significant 
rainfall was forecast within the 72-hour forecast window, maintenance work that may 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-10 


December 2011 
Project No. 10.005 


Executive Summary 


result in sediment runoff to the stream would be stopped, to allow adequate time to 
complete erosion control measures. 

Bank Stabilization 

SCVWD has committed that no more than half of non-in-kind bank repairs would consist of 
impervious hardscape each year. Equipment used for bank stabilization activities may 
include excavators, bulldozers, and front-end loaders for bank grading and earth-moving 
activities. Staging typically would occur on adjacent access roads. Soil and other repair 
materials typically would be staged in areas that were previously disturbed (i.e., service 
roads, turn-outs]. In some cases, bank stabilization projects may require the installation of 
temporary roads and ramps to access the work site. Where trees may have to be removed, 
SCVWD would target non-native trees for removal. The average duration of bank 
stabilization work is 10 working days per site. 

Sediment Removal 

Sediment may be removed by excavators, grade-alls, draglines, and/or loaders. Temporary 
dams, pipes, and existing overflow channels would be used if water needed to be bypassed 
around the site during work. Sediment removed from the channel typically would be placed 
in 10- or 20-cy dump trucks, and prepared for off-site hauling and disposal. Stockpiling of 
sediment to allow for drying before disposal only would be done when sufficient space 
would allow the temporary piling of material; however, this would not be typical. The 
average duration of a sediment removal project would be 10 days, although larger work 
sites would require up to 6 weeks to complete. 

Vegetation Management 

Vegetation management techniques would include hand removal, using small tools and 
hand-held equipment (chainsaws, weed-eaters, and flamers], mechanical removal using 
heavy equipment, herbicide application, and grazing. Heavy equipment used for vegetation 
removal may include a disc attachment on a tiller to clear aboveground herbaceous plants 
on the upland parcels outside of stream banks; flail mowers to cut weeds and other non¬ 
native vegetation on the inside slope of some levees or stream banks; or a backhoe or 
rubber-tracked excavator, used for removing material from the channel. 

New techniques (described in the 2012 SMP Manual [Appendix A]] would include grazing 
and the use of flamers to manage vegetation. Flaming would involve the use of a hand-held, 
propane gas-powered flamer to control weed seedlings. In limited circumstances, SCVWD 
may use various domestic animals to provide non-specific weed control. 

Herbicide application in upland areas typically would be sprayed from a truck-mounted rig 
or applied using a controlled drop applicator. Spray trucks would be used to apply 
herbicides to areas such as maintenance roads. Herbicides may be selectively sprayed 
instream, following appropriate biological surveys and clearances. Only herbicides and 
surfactants approved for aquatic use by the U.S. Environmental Protection Agency and 
registered for use by the California Department of Pesticide Regulation would be used for 
SCVWD’s aquatic vegetation control work. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-11 


December 2011 
Project No. 10.005 



Executive Summary 


The SMP Update includes an expanded list of herbicide types and a broader area of 
application. The Proposed Project would enable herbicide use within the Pajaro River 
watershed and incorporate surfactants under restricted conditions as an application aid. 
Additional application adjustments would include a longer work window, application in 
upland areas, and application in sensitive species habitat under certain restrictions. 

Management of Animal Conflicts 

Management of animal conflicts generally would be conducted with the use of hand-placed 
materials using small tools and hand-held equipment. This would include establishing 
buffers and biological repellants, trapping, as well as lethal baiting and fumigant 
applications. Heavy equipment may be used to modify habitat conditions and reduce or 
eliminate burrowing animals through surface compaction, filling of burrows with slurry, 
and tilling areas to destroy food sources. All lethal control methods would be designed to 
comply with County Agriculture Commission requirements and would be implemented 
using BMPs that would be designed to avoid or minimize effects on special-status species. 

Phase 3: Annual Reporting 

At the conclusion of each year's maintenance season, a Post-Construction Report would be 
developed and submitted to the appropriate resource agencies. This report would include a 
summary of the year's maintenance projects, describing what activities occurred and where, 
a description and confirmation of the restoration and mitigation activities implemented, 
and other SMP updates as necessary. 

Program Review 

Following the submittal of the Post-Construction Report, resource agency staff would be 
invited to meet with SCVWD staff for a "lessons learned meeting," usually in February or 
March of each year, to evaluate the effectiveness of both resource protection and 
maintenance methods used in the preceding construction season. The information 
discussed at these annual lessons learned meetings would be used to adaptively manage the 
BMPs and SMP processes to improve SMP effectiveness. 

Programmatic Impact Avoidance, Minimization, and Compensatory 
Mitigation 

A three-part sequence would address Proposed Project impacts. First, the SMP Update itself 
has several built-in or internal restrictions and protocols to avoid or minimize impacts by 
limiting how and where maintenance could occur. Second, the operational implementation 
of maintenance activities would be required to adhere to specific BMPs. Thirdly, residual 
impacts remaining after these two impact avoidance and minimization efforts would be 
addressed through compensatory mitigation. These three approaches to address potential 
Proposed Project impacts are further described next. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-12 


December 2011 
Project No. 10.005 



Executive Summary 


Programmatic Impact Avoidance and Minimization 

The SMP Update would incorporate the following overarching principles to protect natural 
resources and guide decision-making for stream maintenance activities and projects: 

Principle 1: SCVWD will implement all routine stream maintenance activities according to 
the process and protocols established in the SMP Update. 

Principle 2: Decisions regarding the necessity of routine sediment removal and 
vegetation management activities (to restore channel flow capacities] will be 
made following the thresholds and standards provided in the District's 
Maintenance Guidelines and Asset Management Program. 

Principle 3: SCVWD will implement measures to avoid and minimize impacts to native 
species and habitat. 

Principle 4: All maintenance activities will be performed in a manner that has the least 
impact to the natural flora, fauna, and aquatic resources while meeting SMP 
Update objectives. 

Supporting these SMP principles, measures and protocols would be applied by SCVWD for 
effective work results while avoiding or minimizing potential environmental impacts, 
including conducting no work above the 1,000-foot contour level, identifying the minimum 
maintenance need, and considering existing channel features in analysis and design. 

Best Management Practices 

Maintenance activities would incorporate a range of measures to minimize undesired 
effects on the environment and to implement the SMP principles described above. BMPs 
specifically created for the SMP Update would encompass the range of proposed 
maintenance activities and the environmental conditions of the Project Area. Types of BMPs 
would include general BMPs that would apply to all work, as well as activity-specific BMPs 
designed to address anticipated effects of certain work activities or particular types of 
resources. See Table 2-12 for a description of the BMPs proposed to be used in the SMP 
Update. 

Compensatory Mitigation 

Summary Status of the 2002 SMP Mitigation Program 

Although not all 2002 SMP Mitigation Program requirements have been met, it is important 
to recognize that the original mitigation requirements were based on the full estimated 
impact of the 2002 SMP work projections. Not all of the projected work has been conducted, 
nor have all the estimated impacts occurred. For tidal wetland impacts in the Santa Clara 
Basin, conducted mitigation has met the full mitigation requirement and provided 21+ acres 
over the mitigation necessary, when considering how much actual work and impacts have 
occurred in tidal wetlands. For freshwater wetland impacts in the Santa Clara Basin, 
conducted mitigation has not satisfied the complete mitigation requirement and is about 76 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-13 


December 2011 
Project No. 10.005 



Executive Summary 


percent in pace with the maintenance work conducted (and impacts] that have occurred. In 
the Pajaro Basin, freshwater wetland impacts have been mitigated fully. 

SMP Update Mitigation Program 

The proposed SMP Update process includes reviewing and renewing the existing 
compensatory mitigation package that was established in 2002. The 2002 SMP Mitigation 
Program that covers the original projected activities (sediment removal and vegetation 
management] would remain in place to provide compensatory mitigation in perpetuity for 
the channels identified in the 2002 work projections. 

As part of the proposed SMP Update process, the compensatory mitigation program 
addresses potential impacts anticipated for work sites that were not included in the original 
SMP work projections and not accounted for in the initial compensatory mitigation package. 
Besides addressing mitigation for these new work sites, the compensatory mitigation 
program has been revised to improve overall mitigation feasibility and quality. A key 
constraint to the original SMP mitigation approach was its emphasis on land acquisition. As 
a result, feasible mitigation was often not available in a manner to support the program's 
needs. For the SMP Update, a broader suite of suitable mitigation approaches has been 
developed to provide increased flexibility while maintaining high mitigation quality. The 
revised mitigation program, discussed in detail in Appendix C] would include the following 
elements: 

■ Acquisition and Restoration Program 

■ Invasive Plant Management Program 

■ Riparian Planting Program 

■ Mitigation for Tree and Shrub Removals 6-12 inches (dbh] 

■ Instream Habitat Complexity Program 

■ Gravel Augmentation in Steelhead Creeks 

■ Species-Targeted Habitat Mitigation 

■ Bank Stabilization Mitigation 

Public Involvement Process 

Scoping Comment Period 

In accordance with State CEQA Guidelines (14 CCR 15082[a], 15103, 15375], SCVWD 
circulated a Notice of Preparation (NOP] of a DSEIR for the Proposed Project on August 31, 
2010 (Appendix B], The NOP, in which SCVWD was identified as lead agency for the 
Proposed Project, was circulated to the public; to local, state, and federal agencies; and to 
other interested parties. The purpose of the NOP was to inform responsible agencies and 
the public that the Proposed Project could have significant effects on the environment and 
to solicit their comments. Comments received in response to the NOP were considered 
during preparation of this DSEIR (Appendix B], 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-14 


December 2011 
Project No. 10.005 




Executive Summary 


Public and Agency Review of the DSEIR 

This document will be circulated to local, state, and federal agencies and to interested 
organizations and individuals who may wish to review and comment on the report. Its 
publication will mark the beginning of a 45-day public review period. Written comments or 
questions concerning this DSEIR should be directed to the name and address listed below. 
Submittal of written comments via e-mail (Microsoft Word format] will be greatly 
appreciated. 

Santa Clara Valley Water District 

Attention: Sunny Williams 

5750 Almaden Expressway 

San Jose, CA 95118-3686 

E-mail: smp_update@valleywater.org 

Subject Line: SMP Update EIR Comments 

All documents mentioned herein or related to the Proposed Project can be reviewed on any 
SCVWD business day between the hours of 8 a.m. and 5 p.m. at SCVWD headquarters, 
located at the address shown above. 

Preparation of FSEIR and Public Hearing 

Written and oral comments received in response to the DSEIR will be addressed in a Final 
Subsequent Environmental Impact Report [FSEIR], which will include all comments 
received, responses to each, and a reprint of the DSEIR, updated as appropriate in 
underline/ strik e out in response to the comments. After review of the FSEIR, SCVWD staff 
will recommend to the SCVWD Board of Directors whether to approve or deny the Proposed 
Project. The Board then will review the FSEIR, consider staff recommendations and public 
testimony, and decide whether to certify the FSEIR and approve or deny the Proposed 
Project. 

If the Board approves the Proposed Project in spite of significant impacts identified by the 
FSEIR that cannot be mitigated, the Board must state in writing the reasons for its actions. A 
Statement of Overriding Considerations must be included in the record of the Proposed 
Project approval and mentioned in the Notice of Determination (14 CCR 15093[c]]. 

Areas of Known Controversy 

No areas of public concern have been identified regarding the SMP Update. 

Key Issues and Significant Impacts 

This section discusses key issues of concern relative to the Proposed Project and the 
conclusions of this document regarding those issues, as well as any significant impacts that 
were identified. This is not a comprehensive discussion of impacts of the Proposed Project; 
the reader is directed to Table ES-1, Summary of Impacts and Mitigation Measures, at the 
end of this chapter. Environmental factors potentially affected by the SMP include: 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-15 


December 2011 
Project No. 10.005 



Aesthetics 

Air Quality 

Biological Resources 

Cultural Resources 

Global Climate Change 

Hazards and Hazardous Materials 

Hydrology and Geomorphology 


Land Use and Planning 
Noise 

Public Services and Utilities 
Recreation 

Traffic and Transportation 
Water Quality 


Chapter 3, Environmental Setting and Impact Analysis, and Chapter 4, Other Statutory 
Considerations of this DSEIR address each of these environmental resource topics and the 
impacts of the SMP Update. 


Temporary Impacts from Maintenance Activities 

In general, the primary adverse impacts of SMP Update activities would be short term and 
would occur during maintenance and the period immediately following maintenance. 
Temporary impacts would include: 

■ adverse effects on aesthetics, dust and air emissions from maintenance vehicles and 
equipment, 

■ effects on riparian and aquatic habitats and associated species, 

■ potential exposure to sites of existing chemical contamination, 

■ potential for accidental releases of hazardous materials associated with 
maintenance vehicles and herbicide use, 

■ discharge of sediments and related effects on water quality, 

■ temporary exposure of the public to elevated noise levels associated with 
maintenance activities, 

■ temporary disruption of recreational opportunities or quality during maintenance, 
and 

■ effects on local traffic from maintenance vehicles and hauling of sediment and other 
debris. 


However, the SMP Update would include a multi-tiered program to avoid or minimize and 
compensate for impacts. First, the SMP Update would involve pre-maintenance impact 
avoidance through the use of maintenance principles. These principles would include 
conducting no unnecessary maintenance or intervention, and to target maintenance 
activities to reduce their impact. Second, during maintenance activities, a variety of BMPs 
would be implemented as part of the Proposed Project. These BMPs would be implemented 
before, during, and following maintenance. The BMPs would include avoidance of impacts, 
reducing the intensity/extent of potential impacts, and revegetation and other on-site 
activities that would be implemented to shorten the duration of site recovery. Finally, 
mitigation measures have been designed to address potential impacts that would remain 
after the implementation of BMPs, including a compensatory mitigation program to offset 
residual impacts related to biological resources and water resources (e.g., those potentially 
significant impacts remaining after implementation of BMPs and other issue specific 
mitigation measures]. With the exceptions of air and greenhouse gas emissions, habitat 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-16 


December 2011 
Project No. 10.005 






Executive Summary 


fragmentation, aesthetics, and noise impacts to sensitive receptors, all short-term impacts 
of the SMP Update would be reduced to a level of insignificance. 

Long-Term Impacts from Maintenance Activities 

Over the long term, SMP Update activities are anticipated to provide a variety of beneficial 
impacts. The Proposed Project would provide channel maintenance to maintain design 
flood conveyance capacity, as well as to help establish a developed riparian corridor along 
the maintained channels, resulting in incrementally improved conditions over time (i.e., 
ecological lift). This would result in enhanced habitat values, improved water quality, and 
better recreational value. 

Several long-term adverse impacts have also been identified, including the potential for SMP 
Update activities to result in cumulative adverse contributions of air emissions or 
greenhouse gases; impacts on biological resources and habitat fragmentation; harm to 
existing archeological or paleontological resources; as well as cumulative land use conflicts, 
noise generation, traffic disruption, and water quality effects. However, BMPs would be 
implemented, consistent with the 2012 SMP Manual, that would include measures to 
address these impacts. Furthermore, mitigation measures (described in Chapter 3.3, 
Biological Resources] would be applied to address cumulative impacts on biological 
resources. With the exception of cumulative impacts associated with air emissions, 
greenhouse gases, and habitat fragmentation, all long-term impacts of the SMP Update 
would be reduced to a level of insignificance. 

Significant and Unavoidable Impacts 

The following impacts have been identified as significant and unavoidable: 

■ Impact AES-3: Temporary Alteration of Visual Character or Quality from 
Maintenance Activities 

■ Impact AES-4: Permanent Alteration of Visual Character or Quality from 
Maintenance Activities 

■ Impact AIR- 1 : Temporary Increase in ROG, NOx, PMio, and PM2.5 Emissions during 
Maintenance Activities 

■ Impact BIO-45: Habitat Fragmentation 

■ Impact GCC-1: Temporary Increase in GHGs during Maintenance Activities 

■ Impact NZ-1: Temporary Exposure of the Public to Noise Levels in Excess of City or 
County Standards 

■ Impact NZ-3: Temporary Substantial Increase in Noise above Ambient Levels 

■ Cumulative Impact AIR-1: Emissions of ROG, NOx, PM10, and PM2.5 

■ Cumulative Impact AIR-2: Emissions of Greenhouse Gases 

■ Cumulative Impact BIO-2: Habitat Fragmentation 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-17 


December 2011 
Project No. 10.005 




Executive Summary 


Alternatives Considered 

The purpose of the alternatives analysis in an EIR is to describe a range of reasonable 
alternatives to the Proposed Project that could feasibly attain most of the objectives of the 
Proposed Project while reducing or eliminating one or more of the Proposed Project's 
significant effects. The range of alternatives considered must include those that offer 
substantial environmental advantages over the Proposed Project and may be feasibly 
accomplished in a successful manner considering economic, environmental, social, 
technological, and legal factors. 

The following alternatives have been evaluated for their feasibility and their ability to 
achieve most of the Proposed Project objectives while avoiding, reducing, or minimizing 
significant impacts identified for the Proposed Project: 

■ No Project Alternative 

■ Reduced Frequency Alternative 

■ Limited Work in Unmodified Channels Alternative 

■ Limited Activities Alternative 

No Project Alternative 

Under the No Project Alternative, SCVWD would continue conducting maintenance 
activities, including CEQA compliance and permitting, on an annual basis following the 
practices in the existing (2002] SMP. This would accomplished either be [1] conducting 
CEQA compliance and permitting on a project-by-project basis, or [2] by extending or 
renewing the existing SMP permits and relying on the prior CEQA document. SCVWD would 
conduct the same maintenance activities as done currently, using existing operation and 
maintenance guidelines and BMPs. One main difference between this alternative and the 
Proposed Project is that the Proposed Project would include an extension of the end of the 
maintenance period, from October 15 to December 31, as long as weather remained dry. If 
project-by-project permitting was implemented, some needed maintenance likely would 
not be conducted during the same season as the need for it was identified, resulting in the 
potential for increased flood risk. Therefore, possibly less maintenance work would get 
accomplished each year. 

If less maintenance work was completed each year, then maintenance activities would be 
performed at each reach less frequently, and/or less work would be completed overall. As a 
result, a variety of impacts would be slightly reduced, compared to the Proposed Project. 
Sediment discharges from areas requiring bank stabilization, combined with increased 
sediment accumulation resulting from the longer period between maintenance activities, 
would result in a greater temporary reduction in conveyance capacity than the Proposed 
Project. Consequently, it is expected that the No Project Alternative would provide a slightly 
lower level of flood protection than the Proposed Project. The existing BMPs, to the extent 
they would not be as protective as the BMPs proposed for the SMP Update, may not reduce 
the impacts of maintenance to the same extent as under the Proposed Project. Furthermore, 
because SCVWD may not know what the mitigation requirements would be more than one 
year in advance, biological impacts would need to be mitigated on an annual basis. Should 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-18 


December 2011 
Project No. 10.005 



Executive Summary 


project-by-project permitting lead to undertaking mitigation in smaller increments, the 
overall mitigation may be less ecologically significant than the comprehensive approach 
proposed by the SMP Update. 

Reduced Frequency Alternative 

Under the Reduced Frequency Alternative, the types of maintenance activities undertaken 
by SCVWD would not change, but the recurrence of sediment removal and vegetation 
management activities would occur less frequently than under the Proposed Project. 
However, bank stabilization, management of animal conflicts, and minor maintenance 
activities would continue to occur as needed. All other aspects of the Proposed Project (e.g., 
the currently proposed BMPs] would be implemented under this alternative. Under the 
Proposed Project, the recurrence of activities is projected for a 10-year period. Typically, 
the need for sediment removal or instream vegetation management is based on field 
observations of reduced channel capacity from sediment accumulation or vegetation 
growth; non-instream vegetation management addresses annual growth, including the 
removal of both pre-emergent and post-emergent vegetation. Under the Reduced 
Frequency Alternative, the recurrence of sediment removal and vegetation management 
activities at any particular location would be half as frequent as under the Proposed Project. 
For example, if a stream reach was projected to need sediment removed in 4 out of 10 years, 
under this alternative, sediment would be removed in 2 out of 10 years. 

Although maintenance activities would occur less frequently, the amount of maintenance 
done during each event would likely need to be greater to fulfill maintenance needs. For 
instance, a greater amount of sediment removal or instream vegetation management would 
need to occur during a maintenance event to maintain the design flood flow conveyance 
capacity during the longer periods between maintenance episodes. A greater amount of 
non-instream vegetation management also would need to occur during a maintenance 
event, to address fire hazards on roads and levees associated with a greater amount of 
vegetation growth. Similarly, different types of maintenance may be necessary (e.g., removal 
of larger trees may require larger equipment]. 

Compared to the Proposed Project, impacts would be theoretically reduced because 
maintenance events would occur less frequently; however, this may be offset by the 
increased intensity associated with the less frequent, larger maintenance events. The 
frequency and intensity of maintenance events would have various impacts. Increased 
sediment accumulation and instream vegetation resulting from the longer period between 
maintenance activities would result in a greater temporary reduction in conveyance 
capacity, and thus an increased flood risk, than the Proposed Project. However, because 
larger maintenance events would occur, flood flow conveyance capacity could be retained 
over the long term. Increased non-instream vegetation growth, resulting from the longer 
period between maintenance activities, would result in greater temporary fire hazards on 
roads and levees than the Proposed Project. 

Limited Work in Unmodified Channels Alternative 

Under the Limited Work in Unmodified Channels Alternative (Limited Work Alternative], 
maintenance activities that could be done in unmodified channels would be limited to 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-19 


December 2011 
Project No. 10.005 



Executive Summary 


within 100 feet upstream and downstream of human-made structures, such as bridges, road 
crossings, stream gages, outfalls, and trash racks. As a result, a reduced amount of annual 
maintenance would occur under this alternative. Maintenance near human-made structures 
would be necessary because it would keep these structures functioning properly and safely. 
Necessary maintenance activities in unmodified channels located away from human-made 
structures would not occur, resulting in increased flood risk or unaddressed maintenance 
needs. All other aspects of the Proposed Project (e.g., the currently proposed BMPs] would 
be implemented under this alternative. 

The primary goal of the Limited Work Alternative would be to reduce impacts to biological 
resources in unmodified channels, as the unmodified channels are believed to have the 
greatest ecological value overall. The majority of impacts to biological resources in 
unmodified channels would be eliminated, but some disturbance and impact to unmodified 
channels would be necessary to maintain human-made structures. Compared to the 
Proposed Project, the Limited Work Alternative may promote the ecological structure and 
function of unmodified reaches by reducing impacts to plant and animal species, riparian 
habitat, and wetlands. To the extent that maintenance activities would support or improve 
ecological structure and function (for instance, create conditions unfavorable to invasive 
exotic species], these benefits would not be realized to the same extent as under the 
Proposed Project. 

Under the Limited Work Alternative, the overall amount of maintenance would likely be 
reduced. As a result, various impacts would be reduced, compared to the Proposed Project. 
Sediment discharges from bank failures that would not be addressed under this alternative 
would result in a greater temporary reduction in conveyance capacity than the Proposed 
Project, and they would have adverse water quality (sedimentation] impacts. In addition, 
because flood flow capacities would not be maintained in these unmodified channels, flood 
risk may increase in these reaches. 

Limited Activities Alternative 

Under the Limited Activities Alternative, those maintenance activities with the greatest 
biological impacts would be eliminated or modified. For bank stabilization activities, no 
hardening of stream banks would be allowed and only "soft" stabilization measures would 
be used. For sediment removal activities, equipment would always be located at the top of 
the bank and would not be allowed in the stream channel. For vegetation management 
activities, no herbicide use would be allowed, and only mechanical vegetation management 
methods would be utilized. For management of animal conflicts, no rodenticide use would 
be allowed. Minor maintenance activities would be conducted as described under the 
Proposed Project. Relying on alternative methods would result in increased efforts to 
accomplish the same degree of necessary maintenance. Alternative methods also may result 
in higher implementation costs and/or less maintenance work getting accomplished each 
year. 

Under the Limited Activities Alternative, the avoidance of the most impactful activities 
would eliminate impacts but may increase others. For instance, eliminating the use of 
herbicides and rodenticides would reduce the potential for impacts on water quality. 
However, repeated hand-vegetation removal would be likely to result in greater trampling 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-20 


December 2011 
Project No. 10.005 



Executive Summary 


of vegetation/habitat than single events of herbicide application. Conducting sediment 
removal from the top of the stream bank may not allow for removal of sediment from 
certain channels that could not be accessed from the top of the bank. Therefore, this 
alternative would be likely to impede sediment removal that would be necessary to 
maintain flood flow conveyance capacity. As a result, the potential flooding risk would 
increase at these locations. 

Furthermore, reliance on alternative methods for implementing maintenance activities 
could result in new and/or increased environmental impacts, compared to the Proposed 
Project. For instance, relying solely on mechanical vegetation management, as opposed to 
herbicides, could result in greater noise and air quality impacts. Finally, restricting bank 
stabilization to "soft" methods could result in inadequate bank protection in instances 
where hard methods were needed for bank stability. This could result in repeated bank 
failures, with adverse impacts on habitat and water quality through direct loss of riparian 
habitat as well as sediment discharges. The need for repeat bank repairs could increase the 
impacts associated with such maintenance activities (e.g., increased air emissions, noise 
impacts]. 

Comparison of Alternatives and the Environmentally Superior Alternative 

Weighing all the issues, the Proposed Project is considered to be environmentally superior. 
Compared to any of the other alternatives, it strikes the most appropriate balance between 
managing flood risk, protecting the ecological integrity of the SMP channels, and addressing 
other short- and long-term impacts associated with proposed maintenance activities. 

However, CEQA requires that an environmentally superior alternative be selected from 
among the alternatives to the Proposed Project. The Reduced Frequency Alternative is 
considered the environmentally superior alternative because by limiting the amount of all 
annual maintenance activities, it would reduce the impacts associated with these activities. 
However, this alternative would provide less overall flood protection than the Proposed 
Project. Although flood flow capacity would be retained in the long-term by conducting 
larger maintenance events, flood risk would increase in the interim because needed 
maintenance events would be delayed so that they occurred no more frequently than every 
5 years. 

The other alternatives were not selected as the environmentally superior alternative for the 
following reasons: 

■ No Project Alternative. Although this alternative would provide only a slight 
reduction in the maintenance of the design flow or appropriate conveyance capacity 
of facilities, maintenance would not necessarily be conducted in a timely manner to 
avoid flood hazards. Furthermore, maintenance activities may not be implemented 
along with a comprehensive mitigation approach and consistent set of BMPs. 
Therefore, flood risk would be greater and, at the same time, more residual impacts 
would remain. 

■ Limited Work Alternative. As a result of reduced maintenance activities in 
unmodified reaches, this alternative would promote the ecological structure and 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-21 


December 2011 
Project No. 10.005 



Executive Summary 


function of these reaches and, therefore, would reduce a variety of impacts related 
to the Proposed Project in those locations. However, this alternative would result in 
increased flood risk along unmodified channels and resulting impacts on 
downstream creek systems. 

■ Limited Activities Alternative. This alternative would slightly reduce impacts to 
biological resources. However, new/increased impacts also could result from the 
use of alternative maintenance methods. This alternative also could result in a 
reduction in the maintenance of the design flow or appropriate conveyance capacity 
of facilities where sediment removal could not occur solely from the top of the bank, 
and increased water quality and habitat impacts where soft bank stabilization 
methods were not effective. 

Summary of Impacts and Levels of Significance 

The impacts of the Proposed Project, proposed mitigation, and significance conclusions are 
discussed in detail in Chapter 3, Environmental Setting and Impact Analysis, and Chapter 4, 
Other Statutory Considerations of this DSEIR. Table ES-1 summarizes the impacts, mitigation 
measures, and levels of significance identified in this document. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-22 


December 2011 
Project No. 10.005 



Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 


Potential Impact 

Level of 
Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

Direct and Indirect Impacts | 

3.1 Aesthetics 

AES-1: Alternation to a Scenic Vista 

LTS 

None Required 

LTS 

AES-2: Alteration to Scenic Resources Viewed 
from a State or County-designated 

Scenic Highway 

LTS 

None Required 

LTS 

AES-3: Temporary Alteration of Visual 

Character or Quality from Maintenance 
Activities 

PS 

MM BIO-1, MM BIO-2, and MM BIO-7 

SU 

AES-4: Permanent Alteration of Visual 

Character or Quality from Maintenance 
Activities 

PS 

MM BIO-1, MM BIO-2, and MM BIO-7 

SU 

AES-5: Substantial Alteration to Day or 
Nighttime Views resulting from 
Additional Light or Glare 

NI 

None Required 

NI 

AES-6: Impacts on Aesthetics Associated with 
sediment Disposal/Reuse 

LTS 

None Required 

LTS 

3.2 Air Quality 

AIR-1: Temporary Increase in ROG, NOx, 

PMio, and PM 2.5 Emissions during 
Maintenance Activities 

PS 

MM AIR-1A: Reduction in Fleet Emissions, 

MM AIR-1B: Off-site NOx Emissions Mitigation 
Program, MM AIR-1C: NOx Emissions Offsets 

LTS/SU 

AIR-2: Diesel PM Health Risk during 
Maintenance Activities 

LTS 

None Required 

LTS 

AIR-3: Creation of Objectionable Odors 

LTS 

None Required 

LTS 

3.3 Biological Resources 

BIO-1: Loss or Disturbance of Wetlands and 
Other Waters 

PS 

MM BIO-1: Implement Compensatory Mitigation for 
Wetlands and Other Waters 

LTS 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 


ES-23 

December 2011 
Project No. 10.005 


Final Subsequent Environmental Impact Report 












Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 



Potential Impact 

Level of 
Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

BIO-2: 

Loss or Disturbance of Woody Riparian 
Vegetation 

PS 

MM BIO-2: Implement Compensatory Mitigation for 
Woody Riparian Vegetation 

LTS 

BIO-3: 

Disturbance of Sensitive Plant 
Communities 

PS 

MM BIO-3: Implement Compensatory Mitigation for 
Serpentine Communities 

LTS 

BIO-4: 

Impacts to Serpentine-Associated 
Special-Status Plant Species 

PS 

MM BIO-4: Implement Compensatory Mitigation for 
Serpentine-Associated Special-Status Plant Species 

LTS 

BIO-5: 

Impacts to Non-Serpentine Special- 
Status Plant Species 

PS 

MM BIO-5: Implement Compensatory Mitigation for 
Impacts to Non-Serpentine Special-Status Plant Species 

LTS 

BIO-6: 

Impacts to Serpentine-Associated 
Special-Status Invertebrates 

PS 

MM BIO-6: Implement Compensatory Mitigation for 
Impacts to Serpentine-Associated Special-Status 
Invertebrates 

LTS 

BIO-7: 

Loss of Ordinance Trees 

PS 

MM BIO-7: Tree Replacement 

LTS 

BIO-8: 

Impacts on Steelhead 

PS 

MM BIO-1, MM BIO-2, MM BIO-8: Augmentation of 
Spawning Gravel, and MM BIO-9: Augmentation of 
Instream Complexity for Non-Tidal Stream Fish 

LTS 

BIO-9: 

Impacts on the Pacific Lamprey and 
Monterey Roach 

PS 

MM BIO-1, MM BIO-2, and MM BIO-9 

LTS 

BIO-10: 

Impacts on the Longfin Smelt and 

Green Sturgeon 

PS 

MM BIO-1 

LTS 

BIO-11: 

Impacts on the California Tiger 
Salamander 

PS 

MM BIO-1, MM BIO-2, and MM BIO-10: 
Implement Compensatory Mitigation for 
the California Tiger Salamander 

LTS 

BIO-12: 

Impacts on the California Red-Legged 
Frog 

PS 

MM BIO-1, MM BIO-2, 

and MM BIO-11: Implement Compensatory Mitigation 
for the California Red-Legged Frog 

LTS 

BIO-13: 

Impacts on the Foothill Yellow-Legged 
Frog 

LTS 

None Required 

LTS 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-24 


December 2011 
Project No. 10.005 









Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 


Potential Impact 

Level of 
Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

BIO-14: Impacts on Non-Special-Status Fish and 
Amphibians 

PS 

MM BIO-1, MM BIO-2, and MM BIO-9 

LTS 

BIO-15: Impacts on Essential Fish Habitat 

LTS 

None Required 

LTS 

BIO-16: Impacts on the Western Pond Turtle 

PS 

MM BIO-1, MM BIO-2, and MM BIO-9 

LTS 

BIO-17: Impacts on the California Horned 

Lizard 

LTS 

None Required 

LTS 

BIO-18: Impacts on the Black Skimmers 

LTS 

None Required 

LTS 

BIO-19: Impacts on the Western Snowy Plover 

LTS 

None Required 

LTS 

BIO-20: Impacts on the California Clapper Rail 
and Alameda Song Sparrow 

PS 

MM BIO-1 

LTS 

BIO-21: Impacts on the California Black Rail 
and Bryant’s Savannah Sparrow 

LTS 

None Required 

LTS 

BIO-22: Impacts on the San Francisco Common 
Yellowthroat 

LTS 

None Required 

LTS 

BIO-23: Impacts on the Least Bell’s Vireo 

PS 

MM BIO-2, and MM BIO-12: Implement Compensatory 
Mitigation for the Least Bell’s Vireo 
(MM BIO-12A or MM BIO-12B) 

LTS 

BIO-24: Impacts on the Burrowing Owl 

PS 

MM BIO-13: Implement Compensatory Mitigation for 
the Burrowing Owl 

LTS 

BIO-25: Impacts on the Golden Eagle and Bald 
Eagle 

LTS 

None Required 

LTS 

BIO-26: Impacts on the American Peregrine 
Falcon 

LTS 

None Required 

LTS 

BIO-27: Impacts on the Yellow Warbler 

PS 

MM BIO-2 and MM BIO-14: Implement Compensatory 
Mitigation for the Yellow Warbler 

LTS 

BIO-28: Impacts on the Yellow-Breasted Chat 

PS 

MM BIO-12 (MM BIO-12A or MM BIO-12B] 

LTS 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-25 


December 2011 
Project No. 10.005 








Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 


Potential Impact 

Level of 
Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

BIO-29: Impacts on the Grasshopper Sparrow 

LTS 

None Required 

LTS 

BIO-30: Impacts on the Northern Harrier 

LTS 

None Required 

LTS 

BIO-31: Impacts on the White-tailed Kite and 
Loggerhead Shrike 

LTS 

None Required 

LTS 

BIO-32: Impacts on the Redhead, Short-Eared 
Owl, Long-Eared Owl, Vaux’s Swift, and 
Olive-Sided Flycatcher 

LTS 

None Required 

LTS 

BIO-33: Impacts on the Tricolored Blackbird 

LTS 

None Required 

LTS 

BIO-34: Impacts on Non-Breeding, Special- 
Status Birds 

LTS 

None Required 

LTS 

BIO-35: Impacts on the Salt Marsh Harvest 
Mouse and Salt Marsh Wandering 

Shrew 

PS 

MM BIO-1 

LTS 

BIO-36: Impacts on the San Francisco Dusky- 
Footed Woodrat 

LTS 

None Required 

LTS 

BIO-37: Impacts on the Pallid Bat 

PS 

MM BIO-15: Provide Alternative Bat Roost 

LTS 

BIO-38: Impacts on the Western Red Bat and 
Townsend’s Big-Eared Bat 

LTS 

None Required 

LTS 

BIO-39: Impacts on Non-Special-Status Bats 

LTS 

None Required 

LTS 

BIO-40: Impacts on the San Joaquin Kit Fox 

LTS 

None Required 

LTS 

BIO-41: Impacts on the American Badger and 
Ringtail 

LTS 

None Required 

LTS 

BIO-42: Impacts on the Mimic Tryonia 

LTS 

None Required 

LTS 

BIO-43: Impacts on the Pacific Harbor Seal 

LTS 

None Required 

LTS 

BIO-44: Introduction of Invasive Species 

PS 

MM BIO-16: Invasive Plant Species Management 
Program 

LTS 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 


ES-26 

December 2011 
Project No. 10.005 


Final Subsequent Environmental Impact Report 









Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 


Potential Impact 

Level of 

Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

BIO-45: Habitat Fragmentation 

SU 

None Available 

SU 

BIO-46: Conflicts with Adopted Habitat 
Conservation Plans or Natural 
Community Conservation Plans 

LTS 

None Required 

LTS 

BIO-47: Resuspension of Mercury 

LTS 

None Required 

LTS 

3.4 Cultural Resources 

CR-1: Disturbance to Known and Previously 

Undiscovered Archaeological or 

Historic Resources 

LTS 

None Required 

LTS 

CR-2: Discovery of Human Remains 

LTS 

None Required 

LTS 

CR-3: Impacts to Sensitive Paleontological 

Resources as a Result of Maintenance 
Activities 

LTS 

None Required 

LTS 


3.5 Global Climate Change 


GCC-1: Temporary Increase in GHGs during 
Maintenance Activities 

PS 

MM AIR-1A and MM GCC-1A: On-site or Off-site GHG 
Emissions Mitigation Program, 
or MM GCC-1B: GHG Emissions Offsets 

LTS/SU 

3.6 Hazards and Hazardous Materials 

HAZ-1: Use, Transport, or Accidental Release 
of Hazardous Materials such that a 
Significant Hazard to the Public or 
Environment Would Result 

LTS 

None Required 

LTS 

HAZ-2: Potential to Interfere with Emergency 
Response 

LTS 

None Required 

LTS 

HAZ-3: Be Located on a Known Existing 
Contaminated Site 

LTS 

None Required 

LTS 

HAZ-4: Be Located on a Previously 

LTS 

None Required 

LTS 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-27 


December 2011 
Project No. 10.005 













Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 


Potential Impact 

Level of 

Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

Undiscovered Contaminated Site 

HAZ-5: Create Safety Hazards or Releases of 
Hazardous Materials in Proximity to a 
School 

LTS 

None Required 

LTS 

HAZ-6: Exacerbate Wildland Fires 

LTS 

None Required 

LTS 

HAZ-8: Disposal of Contaminated Sediments 

LTS 

None Required 

LTS 

3.7 Hydrology and Geomorphology 

HYD-1: Short-Term Instream Erosion or 
Sedimentation from Sediment 
Management Activities 

LTS 

None Required 

LTS 

HYD-2: Long-Term Instream Erosion or 

Sedimentation from Sediment Removal 
Activities 

B 

None Required 

B 

HYD-3: Short-Term Erosion or Sedimentation 
from Vegetation Management 

Activities 

LTS 

None Required 

LTS 

HYD-4: Short-Term Erosion, or Sedimentation 
from Bank Stabilization Activities 

LTS 

None Required 

LTS 

HYD-5: Long-Term Erosion and Sedimentation 
from Vegetation Management and 

Bank Stabilization Activities 

B 

None Required 

B 

HYD-6: Harm to People, Structures, or Water 
Quality from Flooding 

B 

None Required 

B 

HYD-7: Alterations to the Recharge, Quality, or 
Quantity of Groundwater 

B 

None Required 

B 

HYD-8: Occurrence of Seiche, Tsunami, or 
Mudflow 

NI 

None Required 

NI 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

ES-28 


December 2011 
Project No. 10.005 


Final Subsequent Environmental Impact Report 










Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 


Potential Impact 

Level of 

Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

HYD-9: Geomorphic Effects of Sediment Reuse 

LTS 

None Required 

LTS 

HYD-10: Creation of Runoff Water and 

Depletion of Surface Water Supplies 

LTS 

None Required 

LTS 

HYD-11: Short-Term Erosion and 

Sedimentation from Minor 
Maintenance, Management of Animal 
Conflicts, and Canal Maintenance 
Activities 

B 

None Required 

B 

HYD-12: Long-Term Erosion and 

B 

None Required 

B 


Sedimentation from Minor 
Maintenance, Management of Animal 
Conflicts, and Canal Maintenance 
Activities 


3.8 Land Use and Planning 

LU-1: Division of Existing Neighborhoods or 

Communities 

LTS 

None Required 

LTS 

LU-2: Incompatibility with Adjacent Land 

Uses 

LTS 

None Required 

LTS 

LU-3: Compatibility with Land Use Plans and 
Policies 

LTS 

None Required 

LTS 

3.9 Noise 

NZ-1: Temporary Exposure of the Public to 

Noise Levels in Excess of City or County 
Standards 

PS 

None Available 

SU 

NZ-2: Generate Groundborne Vibrations 

NI 

None Required 

NI 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-29 


December 2011 
Project No. 10.005 






Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 

Potential Impact 

Level of 

Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

NZ-3: Temporary Substantial Increase in 

Noise above Ambient Levels 

PS 

None Available 

SU 

3.10 Public Services and Utilities 

PSU-1: Effects on Public Facilities and Services 

LTS 

None Required 

LTS 

PSU-2: Disruption to Utilities and Service 

System Facilities 

LTS 

None Required 

LTS 

PSU-3: Insufficient Available Water Supplies 
resulting in the Need for New or 
Additional Water Supply or 

Distribution Facilities 

LTS 

None Required 

LTS 

PSU-4: Disposal of Excavated Sediment and 
Other Materials at Off-Site Locations, 
including Landfills 

LTS 

None Required 

LTS 

3.11 Recreation 

REC-1: Temporary Disturbance of 

Recreational Quality 

LTS 

None Required 

LTS 

REC-2: Permanent Changes to Recreation 
Quality 

B 

None Required 

B 

REC-3: Temporary Disruption of the Use of, or 
Access to, Recreational Facilities 

LTS 

None Required 

LTS 

REC-4: Permanent Use or Access Disruption of 
Recreational Facilities 

NI 

None Required 

NI 

3.12 Traffic and Transportation 

TR-1: Increase in Vehicle Miles Traveled 

LTS 

None Required 

LTS 

TR-2: Substantial Increase in Safety Hazards 

LTS 

None Required 

LTS 

TR-3: Inadequate Emergency Access 

LTS 

None Required 

LTS 

Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 

ES-30 


December 2011 
Project No. 10.005 





Executive Summary 


Table ES-1. Summary of Potential Impacts and Mitigation Measures 


Potential Impact 

Level of 

Significance 
before Mitigation 1 

Mitigation Measures 

Level of 

Significance after 
Mitigation 1 

TR-4: Disruption of Alternative 

Transportation Facilities or Services 

LTS 

None Required 

LTS 

TR-5: Insufficient Parking Capacity 

LTS 

None Required 

LTS 

3.13 Water Quality 

WQ-1: Water Quality Degradation Resulting in 
Violation of Water Quality Standards or 
Waste Discharge Requirements Caused 
by Ground-Disturbing Activities 

LTS 

None Required 

LTS 

WQ-2: Water Quality Degradation Resulting in 
Violation of Water Quality Standards or 
Waste Discharge Requirements Caused 
by Instream Maintenance Activities 

LTS 

None Required 

LTS 

WQ-3: Water Quality Degradation Resulting in 
Violation of Water Quality Standards or 
Waste Discharge Requirements Caused 
by the Accidental Release of Hazardous 
Materials 

LTS 

None Required 

LTS 

WQ-4: Water Quality Degradation Resulting in 
Violation of Water Quality Standards or 
Waste Discharge Requirements Caused 
by the Use of Pesticides, including 
Herbicides 

LTS 

None Required 

LTS 

WQ-5: Water Quality Degradation Resulting in 

LTS 

None Required 

LTS 


Violation of Water Quality Standards or 
Waste Discharge Requirements Caused 
by the Disturbance of Existing 
Contamination 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-31 


December 2011 
Project No. 10.005 







Table ES-1. Summary of Potential Impacts and Mitigation 


Potential Impact Level of 

Significance 
before Mitigation 1 

WQ-6: Compliance with CWA Section 303(d] LTS 

Total Maximum Daily Loads 

WQ-7: Water Quality Degradation Resulting in LTS 

Violation of Water Quality Standards or 
Waste Discharge Requirements Caused 
by Sediment Handling and Disposal 

WQ-8: Create or Contribute Runoff Water that B 

Would Provide Substantial Additional 
Sources of Polluted Runoff 

WQ-9: Alterations to the Quality of B 

Groundwater 


Cumulative Impacts 


AIR-1: Emissions of ROG, NOx, PMio, and PM 2.5 PS 

AIR-2: Emissions of Greenhouse Gases PS 

BIO-1: Effects on Biological Resources PS 

BIO-2: Habitat Fragmentation PS 

CR-1: Effects on Cultural Resources LTS 

LU-1: Land Use Conflicts LTS 

NZ-1: Project-Related Noise Emissions LTS 

TR-1: Disruption to Automobile Traffic LTS 

Patterns 

PSU-1: Effects on Public Services and Utilities B 

WQ-1: Effects on Water Quality LTS 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


Executive Summary 



MM AIR-1A, MM AIR-1B, and MM AIR-1C LTS/SU 

MM AIR-1A, and MM GCC-1A or MM GCC-1B LTS/SU 

MM BIO-1, MM BIO-2, MM BIO-3, MM BIO-4, MM BIO-5, LTS 

MM BIO-6, MM BIO-7, MM BIO-8, MM BIO-9, 

MM BIO-10, MM BIO-11, MM BIO-12, MM BIO-13, 

MM BIO-14, MM BIO-15, and MM-BIO-16 

None Available SU 

None Required LTS 

None Required LTS 

None Required LTS 

None Required LTS 

None Required B 

None Required LTS 


i-32 


December 2011 
Project No. 10.005 













1 Definitions: 

B Beneficial 

LTS Less-than-Significant 

NI No Impact 

PS Potentially Significant 

SU Significant and Unavoidable 

Source: Compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


ES-: 


Executive Summary 


December 2011 
Project No. 10.005 




Chapter 1 

Introduction 


The Santa Clara Valley Water District (SCVWD] has prepared this Draft Subsequent 
Environmental Impact Report (DSEIR] to provide the public, responsible agencies, and 
trustee agencies with information about the potential environmental effects of the proposed 
Stream Maintenance Program (SMP] Update (SMP Update or Proposed Project], This DSEIR 
was prepared in compliance with the California Environmental Quality Act (CEQA] of 1970 
(as amended] and the State CEQA Guidelines (14 California Code of Regulations [CCR]] 
15000 et seq.]. 

1.1 General Background 

SCVWD is a special district created by the State Legislature to act not only as Santa Clara 
County (County]'s water wholesaler but also as its flood protection agency and the steward 
for its streams and creeks, underground aquifers, and SCVWD-built reservoirs. SCVWD 
carries out its responsibilities in an environmentally responsible and cost effective manner, 
led by a Board of Directors composed of seven members, each elected from geographical 
areas within the county. 

As the County's water wholesaler, SCVWD ensures a dependable supply of clean, safe water 
for homes and businesses. As the agency responsible for local flood protection, the SCVWD 
works diligently to protect Santa Clara Valley residents and businesses from the devastating 
effects of flooding. SCVWD's stream stewardship includes creek restoration and wildlife 
habitat projects, mitigation monitoring, pollution prevention efforts, and a commitment to 
natural flood protection. 

1.2 Proposed Project Background 

SCVWD is responsible for water supply, flood protection, and stream stewardship in Santa 
Clara County, California. SCVWD manages streams, canals, reservoirs, dams, pipelines, 
groundwater percolation facilities, and water treatment plants throughout the county to 
fulfill its responsibilities. SCVWD-owned flood protection facilities require maintenance to 
ensure that the designed function of each facility is maintained. Before 2002, SCVWD 
conducted maintenance activities as needed. In 2002, SCVWD implemented the SMP as an 
ongoing program with an indefinite time horizon to guide routine maintenance activities 
within SCVWD’s creeks and canals. The difference between stream maintenance conducted 
before the SMP (pre-2002] and the initial SMP (2002-2012] is the SMP's comprehensive 
approach to managing and tracking the maintenance work and costs, its monitoring of 
environmental conditions, and its mitigating for the program as a whole, rather than on an 
individual project basis. The SMP is used by SCVWD staff to ensure that routine stream 
maintenance practices are conducted in an efficient, consistent, and environmentally 
sensitive manner. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-1 


December 2011 
Project 10.005 



1. Introduction 


Although the SMP is an ongoing program, the initial 2002 SMP Manual and Final 
Environmental Impact Report used a 20-year planning horizon to forecast SMP activities 
and consid e r pot e ntial e nvironm e ntal e ff e cts . In 2009, SCVWD initiated an SMP Update 
process to renew necessary SMP permits as well as to review and update the SMP Manual 
and environmental compliance documentation. For the purposes of regulatory permitting. 
Tthe SMP Update (including the 2012 SMP manual and this CEQA document] is intended to 
cover the 10-year planning period beginning in 2012 and ending in 2022. These SMP 
Update documents are intended to fully replace the original documents that guided the SMP 
from its inception through 2011. In general, the SMP Update is a continuation of past 
routine creek and canal maintenance activities in most of the same areas, using many of the 
same techniques. The SMP Update includes some new work areas and new work activities. 
More details regarding the SMP Update are provided in Chapter 2, Project Description. 

The 2012 SMP Manual (included as Appendix A in this DSEIR] and the contents of the DSEIR 
are meant to be read as complementary volumes. As such, the DSEIR references or 
summarizes information presented in the 2012 SMP Manual frequently to avoid repeating 
information. The reader is encouraged to review the 2012 SMP Manual while reviewing the 
DSEIR. 

1.3 Overview of CEQA Requirements and the 2002 SCVWD 
Stream Maintenance Program EIR 

CEQA is the cornerstone of environmental law and policy in California. CEQA's primary 
objectives are to (State CEQA Guidelines Section 15002]: 

■ ensure that the significant environmental effects of proposed activities are disclosed 
to decision makers and the public; 

■ identify ways to avoid or reduce environmental damage; prevent environmental 
damage by requiring implementation of feasible alternatives; and avoid, minimize, 
reduce and/or compensate for environmental impacts through implementation of 
mitigation measures; 

■ disclose the reasons for agency approval of projects with significant environmental 
effects; 

■ foster multidisciplinary interagency coordination in the review of projects; and 

■ allow for public participation in the planning process. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-2 


December 2011 
Project 10.005 



1. Introduction 


With certain strictly limited exceptions, CEQA requires all state and local government 
agencies to consider the environmental consequences of projects over which they have 
discretionary authority before taking action on those projects. It establishes both 
procedural and substantive requirements that agencies must satisfy to meet CEQA's 
objectives. For example, the agency with decision-making authority (the lead agency] must 
first assess whether a proposed project would result in significant environmental impacts. If 
the project could result in significant environmental impacts, CEQA requires that the agency 
prepare an environmental impact report (EIR], analyzing both the proposed project and a 
range of feasible alternatives. 

As described in Section 15121(a) of the State CEQA Guidelines, an EIR is a public 
information document that assesses potential environmental effects of a proposed project 
as well as identifies mitigation measures and alternatives to the project that could reduce or 
avoid adverse environmental impacts (14 CCR 15121 [a]). Other key procedural 
requirements include developing a plan for mitigation measure reporting and monitoring, 
and carrying out specific noticing and distribution steps to facilitate public involvement in 
the environmental review process. 

In 2001, for its SMP the SCVWD complied with CEQA through a comprehensive evaluation 
and disclosure of potential environmental effects. This included the preparation of a public 
Draft Environmental Impact Report (DEIR) and a Final Environmental Impact Report 
(FEIR), which incorporated public comments and responses to comments on the DEIR. A 
Notice of Determination was filed on July 12, 2002 with the State Clearinghouse (SCH No. 
200102055), completing the CEQA review requirements for the SMP. The requirements and 
policies of the SMP were finalized in 2002 when SCVWD received authorizations from all 
the permitting agencies with jurisdiction over the program, as shown in Table 2-10 in 
Chapter 2, Project Description. 

1.3.1 CEQA Requirements for Subsequent EIR 

The SMP that was evaluated in SCVWD's certified 2002 EIR was intended to be 
implemented indefinitely and, under ordinary circumstances, the EIR should have been 
sufficient to cover implementation of the SMP indefinitely. 

According to Section 15162 of the State CEQA Guidelines, when an EIR has been certified for 
a project, no subsequent EIR shall be prepared for that project unless the lead agency 
determines, on the basis of substantial evidence in the light of the whole record, one or 
more of the following: 

■ Substantial changes are proposed in the project which will require major revisions 
of the previous EIR due to the involvement of new significant environmental effects 
or a substantial increase in the severity of previously identified significant effects; 

■ Substantial changes occur with respect to the circumstances under which the 
project is undertaken which will require major revisions of the previous EIR due to 
the involvement of new significant environmental effects or a substantial increase in 
the severity of previously identified significant effects; or 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-3 


December 2011 
Project 10.005 



1. Introduction 


■ New information of substantial importance, which was not known and could not 
have been known with the exercise of reasonable diligence at the time the previous 
EIR was certified as complete shows any of the following: 

o The project will have one or more significant effects not discussed in the 
previous EIR; 

o Significant effects previously examined will be substantially more severe 
than shown in the previous EIR; 

o Mitigation measures or alternatives previously found not to be feasible 
would in fact be feasible, and would substantially reduce one or more 
significant effects of the project, but the project proponents decline to adopt 
the mitigation measure or alternative; or 

o Mitigation measures or alternatives which are considerably different from 
those analyzed in the previous EIR would substantially reduce one or more 
significant effects on the environment, but the project proponents decline to 
adopt the mitigation measure or alternative. 

Section 15162 also states that a subsequent EIR shall be given the same notice and public 
review as required under Section 15087 or Section 15072. A subsequent EIR shall state 
where the previous document is available and can be reviewed. 

SCVWD has determined that its 2002 SMP and related circumstances have changed 
substantially enough that the preparation of a Subsequent EIR is appropriate. Specifically, 
the following changes to the SMP contributed to this decision: 

■ Maintenance activities are being proposed in new locations not included in the 2002 
SMP. 

■ At some existing locations, different types of maintenance activities are now being 
proposed. 

■ New maintenance activities are being proposed. 

■ SCVWD is proposing a modified approach to mitigation than what was adopted 
under the 2002 EIR. 

In addition, several changes in the physical and regulatory environment have occurred, as 
follows: 


■ Several species are now listed as threatened or endangered under either the 
California or federal Endangered Species Act that were not listed in 2002. 

■ CEQA has been updated with additional requirements regarding the analysis of 
greenhouse gas emissions and global climate change. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-4 


December 2011 
Project 10.005 



1. Introduction 


1.4 Public Involvement Process 

As described above, public disclosure and dialogue are priorities under CEQA. Accordingly, 
CEQA mandates two periods during the SEIR process when public and agency comments on 
the impacts of the Proposed Project are solicited: during the scoping comment period, and 
during the review period for the DSEIR. CEQA and the State CEQA Guidelines also encourage 
lead agencies to hold public meetings or hearings to review both the draft and final versions 
of an SEIR. Brief descriptions of these milestones are provided below, as they apply to this 
document. 

1.4.1 Scoping Comment Period 

Scoping refers to the public outreach process used under CEQA to determine the coverage 
and content of an SEIR. The scoping comment period offers an important opportunity for 
public review and comment in the early phases of a project. The scoping process for an SEIR 
is typically initiated by publication of the Notice of Preparation (NOP] required by CEQA, 
which provides formal notice to the public and to interested agencies and organizations that 
a DSEIR is in preparation. During the scoping period, agencies and the public are invited to 
comment on the project, the approach to environmental analysis, and any issues of concern 
to be discussed in the DSEIR. Scoping also can assist the lead agency with identification of 
project alternatives and mitigation measures. CEQA does not require public meetings 
during the scoping phase. 

In accordance with State CEQA Guidelines (14 CCR 15082[a], 15103, 15375], SCVWD 
circulated an NOP for the Proposed Project on August 31, 2010 (Appendix B], The NOP, in 
which SCVWD was identified as lead agency for the Proposed Project, was circulated to the 
public; to local, state, and federal agencies; and to other interested parties. The purpose of 
the NOP was to inform responsible agencies and the public that the Proposed Project could 
have significant effects on the environment and to solicit their comments so that any 
concerns raised could be considered during the preparation of the DSEIR. In addition, 
SCVWD held a public scoping meeting on September 22, 2010, to provide the public with 
another opportunity to comment. Comments received in response to the NOP are included 
in Appendix B, and the preparers of this DSEIR considered these comments. No comments 
were received at the public scoping meeting. 

1.4.2 Dr a ft EIR DSEIR Comment Period 

After the DSEIR is completed, the District will issue a notice of availability, providing 
agencies and the public with formal notification that the document is available for review. 
The notice will be sent to the State CEQA Clearinghouse, all responsible and trustee 
agencies, any person or organization requesting a copy, and the county clerk's office for 
posting. The notice also will be published in a general-circulation newspaper. These actions 
will trigger a 45-day public review period, during which the District will receive and collate 
public and agency comments on the project and the document. 

SCVWD will host a public hearing approximately 30 days after release of the document. The 
purpose of public circulation and the public hearings are to provide agencies and interested 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-5 


December 2011 
Project 10.005 



1. Introduction 


individuals with opportunities to comment on or express concerns regarding the contents 
of the DSEIR. 

For those interested, written comments or questions concerning this DSEIR can be 
submitted within this review period and directed to the name and address listed below. 
Submittal of written comments via e-mail (Microsoft Word format] will be greatly 
appreciated. 

Santa Clara Valley Water District 
Attention: Sunny Williams 
5750 Almaden Expressway 
San Jose, CA 95118-3686 

E-mail: smp_update@valleywater.org 
Subject Line: SMP Update EIR Comments 

All documents mentioned herein or related to the Proposed Project can be reviewed on any 
SCVWD business day between the hours of 8:00 a.m. and 5:00 p.m. Monday through Friday 
at SCVWD headquarters, located at the address shown above, or on the SCVWD Web site at 
www.valleywater.org under Quick Links, Public Review docs. The documents also will be 
available at the libraries listed below during their normal operating hours. 

Dr. Martin Luther King, Jr. Library 
150 E. San Fernando Street 
San Jose, CA 95112 

Morgan Hill Public Library 
660 W. Main Avenue 
Morgan Hill, CA 95037 

Palo Alto Public Library 
1213 Newell Road 
Palo Alto, CA 94303 

Cupertino Public Library 
10800 Torre Avenue 
Cupertino, CA 95014-3207 

Milpitas Public Library 
160 N. Main Street 
Milpitas, CA 95035 

Alviso Library 

5050 N. 1st St. 

San lose. CA 95134 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-6 


December 2011 
Project 10.005 







1. Introduction 


Written and oral comments received in response to the DSEIR will be addressed in the Final 
Subsequent Environmental Impact Report (FSEIR], which will include all comments 
received, responses to each, and a reprint of the DSEIR, updated as appropriate in 
underline/ strik e out in response to the comments. 

1.4.3 Preparation of Fina l EIR FSEIR and Public Hearing 

CEQA requires the lead agency to prepare an FSEIR, addressing all substantive comments 
received on the DSEIR before approving a project. The FSEIR must include a list of all 
individuals, organizations, and agencies that provided comments on the DSEIR, and must 
contain copies of all comments received during the public review period along with the lead 
agency's responses. 

After review of the FSEIR, SCVWD staff will recommend to the SCVWD Board of Directors 
whether to approve or deny the Proposed Project. This governing body then will review the 
FSEIR, consider SCVWD staff recommendations and public testimony, and decide whether 
to certify the FSEIR and approve or deny the Proposed Project. 

If significant impacts are identified in the SEIR that cannot be mitigated, a statement of 
overriding considerations must be included in the record of the Proposed Project approval 
and mentioned in the Notice of Determination, to be filed with the State Office of Planning 
and Research and at the office of the County Clerk (14 CCR 15093[c]]. 

1.5 Organization of this DSEIR 

This DSEIR contains the following components: 

Table of Contents. The Table of Contents include an outline of the document, lists of the 
appendices, tables, and figures, acronyms, and a glossary of significant terms. 

Executive Summary. A summary of the Proposed Project, a description of the issues of 
concern, alternatives to the Proposed Project, and a summary of environmental impacts are 
provided. 

Chapter 1, Introduction. This chapter describes the statutory basis, purpose, and 
organization of the DSEIR and its preparation, review, and certification process. 

Chapter 2, Project Description. This chapter summarizes the Proposed Project, including: a 
description of the Proposed Project purpose and goals; a brief description of the Proposed 
Project area and facilities where the SMP is implemented; the Proposed Project approach 
and activities; Proposed Project implementation and oversight; avoidance and minimization 
measures (best management practices]; and required permits and approvals. 

Chapter 3, Environmental Setting and Impact Analysis. This chapter begins with an 
introductory section which identifies resource areas determined not to be affected by the 
Proposed Project. Chapter 3 then presents thirteen sections that describe existing 
environmental conditions, the Proposed Project's anticipated environmental impacts, and 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-7 


December 2011 
Project 10.005 



1. Introduction 


mitigation measures proposed for any significant impacts. The following resource topics are 
addressed these sections: 

3.1 Aesthetics 

3.2 Air Quality 

3.3 Biological Resources 

3.4 Cultural Resources 

3.5 Global Climate Change 

3.6 Hazards and Hazardous Materials 

3.7 Hydrology and Geomorphology 

3.8 Land Use and Planning 

3.9 Noise 

3.10 Public Service and Utilities 

3.11 Recreation 

3.12 Traffic and Transportation 

3.13 Water Quality 

Chapter 4, Other Statutory Considerations. This chapter addresses the Proposed Project's 
potential to contribute to cumulative impacts in the Project Area. Chapter 4 also outlines the 
Proposed Project's potential to induce growth and identifies significant, irreversible 
environmental changes that could result from implementation of the Proposed Project. 

Chapter 5, Alternatives Analysis. This chapter describes the process through which 
alternatives to the Proposed Project were developed and screened, evaluates their likely 
environmental impacts, and identifies the environmentally superior alternative. 

Chapter 6, Report Preparation. This chapter lists the individuals involved in preparing this 
DSEIR and their responsibilities. 

Chapter 7, References. This chapter provides a bibliography of printed references, Web sites, 
and personal communications used in preparing this DSEIR. 

Appendix A 2012 Stream Maintenance Program Manual 

Appendix B Notice of Preparation and Comments Received 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-8 


December 2011 
Project 10.005 



1. Introduction 


Appendix C 
Appendix D 
Appendix E 
Appendix F 

Appendix G 

Appendix H 

Appendix I 

Appendix J 
Appendix K 
Appendix L 
Appendix M 


2012-2022 SMP Update Mitigation Approach Memorandum 

General Plan Policies and Ordinances 

Air Quality and Greenhouse Gas Emissions Calculations 

Taxonomic Crosswalk between the Jepson Manual First Edition and Second 
Edition (second edition in preparation] 

Special-Status and Locally Significant Plant Species 
Considered but Rejected for Occurrence in the Project Area 

Detailed Descriptions of Special-Status and Locally Significant Plant Species 
Potentially Occurring in the Project Area 

Detailed Descriptions of Special-Status Wildlife Species Potentially 
Occurring in the Project Area 

Pesticide Regulatory Information 

Traffic and Transportation Calculations 

Mitigation Monitoring and Reporting Program 

Fish Relocation Guidelines 


1.6 Impact Terminology 

This DSEIR uses the following terminology to describe the environmental effects of the 
Proposed Project. 

■ A finding of no impact is made when the analysis concludes that the Proposed 
Project would not affect the particular environmental resource or issue. 

■ An impact is considered less than significant if the analysis concludes that a 
substantial adverse change in the environment related to this impact would not 
occur and, therefore, no mitigation is needed. 

■ An impact may be considered significant or potentially significant if the analysis 
determines that a substantial adverse effect on the environment could occur. 
Depending on the nature of the impact and feasibility of mitigation which could be 
implemented, such impacts would result in one of the following two conclusions: 

o An impact is considered less than significant with mitigation if the analysis 
concludes that a substantial adverse change in the environment related to 
this impact would not occur with the inclusion of the mitigation measures 
described. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-9 


December 2011 
Project 10.005 



1. Introduction 


o An impact is considered significant and unavoidable if the analysis 
concludes that a substantial adverse effect on the environment related to 
this impact could occur and no feasible mitigation measures are available to 
reduce the impact to a less-than-significant level. 

■ An impact is considered beneficial if the analysis concludes that a positive change in 
the environment would occur related to this impact. 

■ Mitigation refers to specific measures or activities adopted to avoid or substantially 
reduce a significant impact. 

■ A cumulative impact is the environmental change resulting from the incremental 
impact of a project when added to other related past, present, or reasonably 
foreseeable future projects. Significant cumulative impacts may result from 
individually minor but collectively significant projects. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


1-10 


December 2011 
Project 10.005 



Chapter 2 

Project Description 


2.1 Introduction 

Since the summer work season of 2002, SCVWD has implemented the SMP to guide routine 
maintenance activities within its creeks and canals. In 2009, SCVWD initiated the SMP 
Update process to: 1] review SMP activities and revise the program manual, 2] update its 
environmental compliance documentation, and 3] renew necessary SMP permits. 

Although the SMP is an ongoin g, continuous program (with an indefinite time horizon], the 
2002 SMP Manual and Final Environmental Impact Report used a 20-year planning horizon 
to forecast SMP activities and consid e r pot e ntial e nvironm e ntal e ff e cts . The proposed SMP 
Update (including the revised SMP manual and this document] is intended to address eover 
the 10-year planning period from 2012-2022 for the purposes of regulatory permitting . The 
updated SMP documents are intended to fully replace the original documents that have 
guided the SMP from its inception in 2002 through the present. 

2.1.1 Project Purpose 

As discussed in Chapter 1, Introduction, SCVWD has prepared this Draft Subsequent 
Environmental Impact Report (DSEIR] to provide the public, responsible agencies, and 
trustee agencies with information about the potential environmental effects associated with 
the adoption and implementation of the updated SMP for the 2012-2022 period. The SMP 
was developed to provide guiding policies, specific direction on approach, and regulatory 
authorization for routine stream and canal maintenance. The SCVWD Board of Directors 
(SCVWD Board] adopted a series of Ends Policies to guide SCVWD activities toward 
achieving SCVWD's mission. The SMP integrates several of the Ends Policies in order to 
guide staff in conducting routine maintenance activities and to provide the foundation for 
obtaining regulatory authorizations. The SMP supports updates, as necessary, to meet new 
conditions or maintenance needs of SCVWD. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-1 


December 2011 
Project 10.005 



2. Project Description 


Applicable Ends Policies of the Board of Directors (as of June 2010 J ulv 2011) 


E-l Mission and General Principles 

The mission of SCVWD is to provide for a healthy, safe, and enhanced quality of 
living in Santa Clara County through watershed stewardship and comprehensive 
management of water resources in a practical, cost-effective, and environmentally- 
sensitive manner for current and future generations. 

E-2 Water Supply: There is a reliable, clean water supply for current and future 
generations. 

Goal 2.1 _ Current and future water supply for municipalities. 

industries, agriculture and the environment is reliable. 

Objective 2.1.1 Aggressively protect groundwater basins from the threat of 
contamination and maintain and develop the groundwater 
basms to optimize reliability and to minimize land subsidence 
and salt water intrusion. 

Objective 2.1.2 Protect, maintain and develop local surface water. 

E-3 Natural Flood Protection: There is a healthy and safe environment for residents, 
businesses and visitors, as well as for future generations. 

Goal 3.1 _ Natural flood protection for residents, businesses and visitors 

Objective 3.1.1 Balance environmental quality and protection from flooding. 
in a cost e ff e ctiv e mann e r 


Objective 3.1.2 Preserve flood conveyance capacity. 

E-4 Water Resources Stewardship: There is water resources stewardship to protect 
and enhance watersheds and natural resources and to improve the quality of life in 
Santa Clara County. 

Goal 4.1 _ Healthy creek, aud-bav and other aquatic ecosystems 

Objective 4.1.1 Balance water supply, flood protection and environmental 
stewardship functions. 

Objective 4.1.2 Protect and improve watersheds, streams, and natural 
resources. 


Objective 4.1.3 
Goal 4.2_ 


Promote awar e n e ss the protection of aquatic cr ee k and bay 
ecosystem functions. 

Clean, safe water in creeks and bay 


Objective 4.2.1 Preserve or improve surface and ground water quality for 
beneficial uses. 


Objective 4.2.2 Promote awar e n e ss the protection of water quality and 
stream stewardship. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-2 


December 2011 
Project 10.005 





2. Project Description 


District Mission and the SMP 

Flood protection under the SMP is an integral part of SCVWD's mission, integrating the 
efficient management of SCVWD assets within the context of environmental requirements 
(Ends Policy E-l], Creek maintenance preserves flow capacity of SCVWD creeks to reduce 
the risk of flooding, and improves water quality through the stabilization of eroding creek 
banks and removal of excess sediment (Ends Policies E-3.1 and E-4.2], 

Maintenance of canals ensures that water conveyance systems are functioning, sustainable, 
and able to move water between reservoirs, creeks, percolation ponds, and water treatment 
plants (Ends Policy E-2.1], Water released into creeks and percolation ponds helps to 
replenish local groundwater aquifers and manage environmental needs (Ends Policy E-2.1], 

SMP mitigation measures are designed to avoid, minimize, or mitigate potential impacts in 
balance with the need to conduct work in creeks and canals while carrying out SCVWD's 
mission. 

2.1.2 Project Objectives 

The overall flood management goals of the SMP Update are to maintain the design flow or 
appropriate conveyance capacity of SCVWD facilities, and to maintain the structural and 
functional integrity of SCVWD facilities. To meet these goals and to implement the 
applicable ends policies described above, the SMP Update would prioritize and administer 
maintenance activities to achieve the following objectives: 

■ remove sediment to maintain the hydraulic, safety, and habitat functions of the 
creek systems; 

■ manage vegetation to maintain the hydraulic, safety, and habitat functions of the 
creek systems, and to allow for levee inspections and maintenance access; 

■ stabilize beds and banks of creeks and canals to protect existing infrastructure, 
maintain public safety, reduce sediment loading, protect water quality, and protect 
habitat values; and 

■ avoid, minimize, or mitigate impacts on the environment by incorporating stream 
stewardship measures into maintenance activities. 

The SMP Update also seeks to obtain and maintain multi-year programmatic permits to 
regulate Proposed Project activities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-3 


December 2011 
Project 10.005 



2. Project Description 


2.1.3 Project Background 

SCVWD is responsible for water supply, flood protection, and stream stewardship in Santa 
Clara County, California. SCVWD manages streams, canals, reservoirs, dams, pipelines, 
groundwater percolation facilities, and water treatment plants throughout the county to 
fulfill its responsibilities. SCVWD flood protection facilities require maintenance to maintain 
the designed function of each facility. The routine activities covered by the existing SMP are 
undertaken on SCVWD property and easements in streams, canals, levees, and adjacent 
property. The principal maintenance activities are: 

■ Bank stabilization 

■ Sediment removal 

■ Vegetation management 

■ Management of animal conflicts 

■ Minor maintenance 


Historically, SCVWD has implemented these activities as needed. Therefore, the SMP Update 
would be a continuation of past routine creek and canal maintenance activities in most of 
the same areas using many of the same techniques. The difference between stream 
maintenance conducted before the SMP [pre-2002], and the initial SMP period (2002- 
2012], is the SMP Update's comprehensive approach to managing and tracking the 
maintenance work and costs, monitoring environmental conditions, and providing program 
mitigation. The SMP Update would be used by SCVWD staff to conduct routine stream 
maintenance practices in an efficient, consistent, and environmentally-sensitive manner. 

The existing SMP complied with the requirements of CEQA through a comprehensive 
evaluation and disclosure of potential environmental effects. This included the preparation 
of a public Draft Environmental Impact Report [DEIR] and a Final Environmental Impact 
Report [FEIR], which incorporated public comments and responses to comments on the 
DEIR. A Notice of Determination was filed on July 12, 2002 with the State Clearinghouse 
(SCH No. 200102055], completing the CEQA review requirements for the SMP. The 
requirements and policies for the existing SMP document were finalized in 2002, when 
SCVWD received authorizations from all the permitting agencies with jurisdiction over the 
program. Work under the existing SMP began in 2002. 

Tables 2-1 and 2-2 summarize sediment removal and vegetation management work 
conducted in the SMP's first decade. The tables compare the sediment removal and 
vegetation maintenance work originally projected for the 2002-2012 period with the actual 
work conducted to date between 2002 and 2009. As shown in the tables, projected 
sediment removal activities were greatly overestimated. Table 2-3 summarizes the bank 
stabilization work conducted during 2002-2009. Bank stabilization work was not projected 
as it was uncertain where such work would be needed until after the winter season 
occurred. Table 2-11, at the end of this chapter, highlights key differences between the 
Proposed Project that is being evaluated in this document, and the SMP adopted in 2002. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-4 


December 2011 
Project 10.005 




2. Project Description 


Table 2-1. Sediment Removal, 2002-2009 


Watershed 

Length (miles) 

Volume Removed (cubic yards) 

Projected 

Work 

2002-2012 

Actual Work 
(2002-2009) 

Projected 

Work 

2002-2012 

Actual Work 
(2002-2009) 

Work 

Completed 1 

Avg 

Annual 2 

Work 

Completed 

Avg 

Annual 

Santa Clara Basin 

47 

28.21 

3.53 

730,700 

364,018 

45,502 

Pajaro Basin 

11 

4.13 

0.52 

64,900 

7,274 

909 

Total 

58 

32.34 

4.04 

795,600 

371,292 

46,411 


Notes: 

1. Certain locations may have been the subject of sediment removal more than once during 2002-2009, but 
their lengths are only counted once in this column. 

2. In contrast with (1) above, the average annual length as presented on this table considers locations of 
repeat work. 

Source: Data compiled by Horizon Water and Environment in 2011 


Table 2-2. Vegetation Management, 2002-2009 


Watershed 

Channel Hand Removal 

Herbicide Application 

Projected 

Work 

(miles) 

2002-2012 

Actual Work 
(2002-2009) 

Projected 

Work 

(miles) 

2002-2012 

Actual Work 
(2002-2009) 

Work Length 
Completed 1 

Avg 

Annual 

Work 

Length 2 

Work Length 
Completed 

Avg 

Annual 

Santa Clara 

Basin 

44 

28.49 

3.56 

183 

172.86 

21.6 

Pajaro Basin 

16 

18.25 

2.28 

0 

0 

0 

Stream Total 3 

60 

46.74 

5.84 

183 

172.86 

21.6 


Notes: 

1. Certain locations may have been the subject of s e dim e nt channel hand- removal more than once during the 
2002-2009 period, but their lengths are only counted once in this column. 

2. In contrast with (1) above, the average annual length as presented on this table considers locations of 
repeat work. 

3. Canals are included in lengths 

Source: Data compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-5 


December 2011 
Project 10.005 



2. Project Description 


Table 2-3. Bank Stabilization, 2002-2009 


Watershed 

Length (feet] 

Total Work 
Completed 
(miles) 

Avg Annual 
(miles) 

Hardscape 

Softscape 

In-Kind 

Repair 

Santa Clara Basin 

7,373 

24,621 

1 

6.06 

0.76 

Pajaro Basin 

10 

1,063 

6,403 

1.42 

0.18 

Total 

7,383 

25,684 

6,404 

7.48 

0.94 


Source: Data compiled by Horizon Water and Environment in 2011 


2.1.4 Project Area 

The Project Area includes the portions of Santa Clara County below the 1,000-foot elevation 
contour, as shown in Figure 2-1. SCVWD maintains only those sections of creeks and canals 
where it has fee title or maintenance easements (including property and easements that 
will be acquired in the future], or where the SCVWD Board has provided specific direction. 
The maintenance work area is the stream channel or canal itself, and typically extends past 
the top-of-bank, where access is provided. Where levees have been constructed, the work 
area extends at least to the outside toe of the levee. 

As shown in Figure 2-1, SCVWD is divided into two major hydrologic basins [watersheds]: 
the Santa Clara Basin drains to San Francisco Bay, and the Pajaro River Basin drains to the 
Monterey Bay. The Santa Clara Basin encompasses approximately 716 square miles. The 
Pajaro River Basin covers approximately 1,300 square miles, of which only 370 square 
miles is within Santa Clara County. The Project Area consists of 315 named rivers, streams, 
channels, drains and ditches, and 7 canals. Figures 2-2 through 2-6 (provided at the end of 
this chapter] provide more detailed maps of the Project Area, including the Lower 
Peninsula, West Valley, Guadalupe, Coyote, and Pajaro watersheds. 

The SMP (both the existing SMP and the Proposed Project] does not include maintenance 
activities in or at reservoirs, dams, pipelines, groundwater percolation facilities, or water 
treatment plants. The SMP does include channel maintenance at dam outlet structures 
immediately downstream of reservoirs. The SMP also includes stream maintenance 
upstream of reservoirs, up to the 1,000 feet elevation contour. In addition, work activities 
performed to maintain creek and canal flow conveyance capacity cannot be used to increase 
the designed flow conveyance capacity of the facility; furthermore, work activities cannot be 
performed if they are specifically excluded in the SMP. 

Municipalities within the Project Area include the cities of Campbell, Cupertino, Gilroy, Los 
Altos, Milpitas, Morgan Hill, Monte Sereno, Mountain View, Palo Alto, San Jose, Santa Clara, 
Saratoga, and Sunnyvale, and the towns of Los Altos Hills and Los Gatos. SCVWD does not 
provide maintenance on private property where no easement exists, unless expressly 
authorized by the SCVWD Board of Directors. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-6 


December 2011 
Project 10.005 



s:/2010/Horizon/SCVWD/GIS/Layouts/Fig1 ProjectArea.mxd (05.16.11) mg 


San 
Francisco 
Bay 


SAN L> ' 
BIATEO / 
COUNTS .. 



Detail Area 



Pacific 

Ocean 


Elevation (feet) 

Below Sea Level 


□ 0-10 


^ 10 -20 


^ 20-30 


H 30 - 40 


o 

LO 

o 

0 



50-100 
100-250 
250 - 500 
500- 1,000 
1,000- 1,500 
Above 1,500 


- County Boundary 

Major Hydrologic Features 
—(#)— Major Roads 

- Upper Elevation Boundary of SMP 

- Watershed Boundaries 


A 

N 

1 inch = 7.75 miles 


I Miles 


2.5 


10 


Horizon 

VVAlift •-* IV*- tUHKIvr 


Figure 2-1: Project Area 




















































2. Project Description 


This page intentionally left blank. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-8 


December 2011 
Project 10.005 



2. Project Description 


2.1.5 Project Channel Types 

SCVWD actively manages over 1,000 miles of channels and creeks. For purposes of this 
document, the channels within SCVWD's jurisdiction are classified as earthen, concrete, 
tunnel, siphon, pipeline, or waterbody. The majority of SMP channels are earthen, having 
earthen channel bed and banks. SCVWD-maintained earthen channels may be either 
engineered and natural stream channels. 

Figure 2-7 (all remaining figures can be viewed at the end of this chapter; photo figures are 
available on the page following their introduction] illustrates a generalized cross section of 
a SCVWD-maintained channel. Note that Figure 2-7 represents the wider and more complex 
channels in the Project Area, similar to the photo of lower Coyote Creek seen in Figure 2-8. 
This figure illustrates many of the channel features (e.g. top-of-bank, toe-of-slope, etc.] that 
are referred to throughout this document. Figure 2-9 provides a generalized illustration of 
an even wider channel alignment where a secondary channel area provides additional 
conveyance. Note that the channel maintenance zone in Figure 2-9 is still defined by the top 
of the outer levees. Figure 2-10 is a photo of the lower Guadalupe River, where this type of 
wide channel alignment with a secondary channel occurs. 

Not all SMP channels are as wide and complex as those shown in Figures 2-7 through 2-10. 
Many of SCVWD's flood protection channels are narrow, linear, and uniform. Figure 2-ll(a] 
depicts a linear trapezoidal channel built in concrete. This type of channel is demonstrated 
by the photo of San Tomas Aquino Creek (Figure 2-12], Figure 2-ll(b] shows a simple 
trapezoidal channel with earthen banks and bed. These channels are very common in the 
Project Area and typically have maintained, grass-lined banks. These channels generally do 
not provide complex or high quality instream features or habitats. The photograph of Sierra 
Creek (Figure 2-13] illustrates this common channel type. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-9 


December 2011 
Project 10.005 



2. Project Description 



Figure 2-8. Coyote Creek 

These photos show the vegetated benches adjacent to the low-flow channel and instream 
bar features. The upper banks are grass covered without taller canopy riparian vegetation. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-10 


December 2011 
Project 10.005 



2. Project Description 



Figure 2-10. Guadalupe River 

The photo shows wide overall channel alignment, with secondary back channel. 



Figure 2-12. San Tomas Aquino Creek 

The photo illustrates a concrete linear trapezoidal channel. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-11 


December 2011 
Project 10.005 











2. Project Description 



Figure 2-13. Sierra Creek 

Sierra Creek is a uniform and linear trapezoidal flood protection channel, characterized by 
limited vegetation, grass lined streambanks, and narrow easement because of adjacent 
homes to left. Maintenance access road is seen to the right. 

2.1.6 Overview of SMP Approach 

Work Area Projections and Annual Work Plans 

Based on the work performed during the SMP 2002-2009, SCVWD has developed 
projections for reasonably anticipated work expected to occur over the next 10-year period 
of its maintenance program (2012-2022], The estimated work projections identify the 
potential creek and maintenance activities by watershed. Although general maintenance 
needs have shown a relatively consistent pattern historically, projections of future stream 
maintenance activities are not meant to represent the exact extent or volume of work that 
may occur. 

Actual stream maintenance activities vary from year-to-year, depending on weather and 
hydrologic conditions, frequency and extent of past maintenance activities, and 
budget/funding availability. Future maintenance needs may occur, consistent with overall 
SMP Update projections, but they may vary from the specific location originally projected. 
Some maintenance activities, such as bank stabilization, cannot be reasonably projected 
because they happen in response to hydrologic events and a variety of site-specific factors. 
Under the SMP Update, maintenance activities would be conducted throughout the program 
area, as long as they do not result in new or more significant environmental effects than 
those evaluated and disclosed in this document. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-12 


December 2011 
Project 10.005 





2. Project Description 


Work site projections for specific activities are described in greater detail below. Based on 
SCVWD's experience during the 2002-2009 period (see Tables 2-1, 2-2, and 2-3], it is likely 
that the actual maintenance conducted during 2012-2022 will be less than the projected 
values. 

Although the SMP Update work projections provide an overview of expected maintenance 
needs over the period 2012-2022 (as described above], maintenance needs in any given 
year would reflect a variety of factors. Each year, SCVWD would develop an annual stream 
maintenance work plan. The work plan would identify the locations, lengths, and areas for 
the given year's proposed maintenance activities. This information would be provided to 
overseeing regulatory agencies in the annual Notice of Proposed Work (NPW] and provided 
at http://www.valleywater.org/Services/StreamMaintenanceProgram.aspx, SCVWD's Web 
site. The actual maintenance activities that were conducted in a given year would be 
summarized and verified in the end of year annual Post Construction Report (PCR], and also 
would be made available to regulatory staff and the public. 

Adaptability 

The existing SMP was designed to be adaptable, to be updated and modified as conditions 
require. One way the SMP Update would achieve this would be by supporting site-specific 
assessments to determine the most effective method to achieve the maintenance goal. As 
conditions allow and technologies and environmental regulations evolve, this would 
support an assessment for work activity modifications that could result in decreased 
impacts. In addition, annual post-maintenance meetings, or "lessons learned" meetings, are 
planned so that SCVWD and resource agency staff can evaluate the effectiveness of both the 
resource protection and the maintenance methods used. These evaluations would be used 
to update Best Management Practices (BMPs] and SMP processes to create a greater 
understanding of how to accomplish environmentally-sensitive, fiscally-sound maintenance 
work. 

2.1.7 Maintenance Guidelines 

SCVWD undertakes three primary assessment programs to provide maintenance guidelines, 
standards, and baseline conditions to help prioritize and guide maintenance activities. 
These three programs include the District's Maintenance Guidelines standards, Watershed 
Asset Management Program, and Geomorphic Data Collection Program. These programs are 
briefly summarized below: 

■ Maintenance Guidelines: In the late 1980s and through the 1990s, the District 
developed the "Engineering-Based Maintenance Guidelines,” or Maintenance 
Guidelines, to document the ongoing need for maintenance of flood protection 
channels to provide adequate flood conveyance capacity. The Maintenance 
Guidelines are organized into five volumes: Northwest Zone, North Central Zone, 
Central Zone, East Zone, and South Zone. A variety of information is provided for 
channels, including: channel location maps, summary data tables, background 
information, maintenance thresholds, maintenance history, and data and 
calculations used to develop the maintenance thresholds. Some creeks have the full 
set of information listed above; while some channels only have a subset of this 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-13 


December 2011 
Project 10.005 



2. Project Description 


information. Most commonly, a maintenance history of past District actions is 
provided for included creeks. The District has not evaluated all the channels in the 
SMP program area and some channel evaluations are more complete than others. 
However, the District frequently relies on the information within the Maintenance 
Guidelines to identify maintenance needs. 

■ Asset Management Program: Begun in 2008, the District has undertaken an 
inventory of all assets within watersheds including creeks, levees, channels, 
mitigation sites, and other features. Through the inventory, District channels and 
other features are assessed for their condition and performance. This assessment 
provides a baseline to develop and optimize maintenance strategies and capital 
improvement programs. It is anticipated that integrating operations, maintenance, 
and capital investment decision-making processes will minimize the cost of owning 
these assets without jeopardizing financial health, the environment, the community, 
or service delivery and reliability. This program improves on existing practices by 
utilizing more advanced tools and protocols (making better use of information 
systems and technology], incorporating enhanced planning processes (using best 
practices and established models], and through increased consistency and 
standardization. 

■ Geomorphology Data Collection Program: In 2011, the District initiated this 
program to provide geomorphic support to the District's capital projects and 
maintenance activities, collect geomorphic data, and develop and maintain a 
geomorphic database. Through the Geomorphology Program, the District is building 
an understanding of creek geomorphology to improve the planning, design, and 
implementation of stream and channel maintenance and capital projects. The 
program's database directly assists the operations and maintenance activities in 
District watersheds and also provides information to support the evaluation of the 
Maintenance Guidelines described above. The Geomorphology Program includes 
collecting standard channel geometry, creek profile, and sediment conditions data. 
The program uses this information to evaluate bankfull flow elevations and 
discharge, and other conditions. Channel photos are included in the database. The 
Geomorphology Program assesses streams and channels to identify existing erosion 
conditions and practical solutions where appropriate, to improve stream stability 
within a dynamic equilibrium. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-14 


December 2011 
Project 10.005 



2. Project Description 


2.2 Maintenance Activities 

The 2012 SMP Update would involve five categories of work activities: bank stabilization, 
sediment removal, vegetation management, management of animal conflicts, and minor 
maintenance. In addition, the SMP Update would include maintenance of canals, which may 
include any of the five activities described above. Full details regarding these maintenance 
activities are provided in Appendix A, and are summarized below. 

2.2.1 Bank Stabilization 

Stabilizing and repairing eroding stream channel banks and levees is a routine SMP activity. 
Based on the maintenance work conducted from 2002-2010, the District stabilizes about 
0.94 mile of stream channel banks or levees on average per year. Although bank 
stabilization is routine and expected, the specific work locations are not certain until after 
each winter season. As a result, this type of maintenance (unlike sediment removal and 
vegetation management] is not a projected work activity. Rather, bank stabilization 
maintenance needs are assessed annually on an as-needed basis. Mitigation for bank 
stabilization projects is also determined on an annual basis depending on the identified 
work need. 

For the SMP Update, the District has slightly revised and reorganized the list of suitable SMP 
bank stabilization treatments. These techniques are described in detail in the 2012 SMP 
Manual (Appendix A] and summarized in Table 2-4, which identifies the SMP's 13 bank 
stabilization treatments (and variations], shows mitigation ratios, describes whether the 
technique uses softscape or hardscape elements, and notes whether the technique requires 
review by regulatory agencies. SCVWD favors the use of soft bank stabilization approaches 
that use bio-technological approaches in place of methods that create more hardened banks. 


Table 2-4. SMP Bank Stabilization Methods (SMP Update 2012) 


ID 

No 

Method 

Mitigation Ratio 

Hard/ 

Softscape 

Requires 

Plan 

Review by 
Agencies 

1 

Earth Repair 

1:1 

Soft 

No 

IB 

Earth Repair with Buried Rock 

1:1 

Soft 

No 

2 

Live Construction 

1:1 

Soft 

No 

2 A 

Live Construction with Boulder Toe 

1:1 if boulder toe is 
vegetated 

1.5:1 if boulder toe is not 
vegetated 

Vegetated: Hybrid 
Not Vegetated: 
Hard 

No 

2B 

Live Construction with Log Toe 

1:1 

Soft 

No 

3 

Contour Wattling 

1:1 

Soft 

No 

3A 

Contour Wattling with Boulder Toe 

1:1 if boulder toe is 
vegetated 

1.5:1 if boulder toe is not 
vegetated 

Soft 

No 

3B 

Contour Wattling with Log Toe 

1:1 

Soft 

No 

4 

Brush Mattress (Brush Layering) 

1:1 

Soft 

No 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-15 


December 2011 
Project 10.005 



2. Project Description 


Table 2-4. SMP Bank Stabilization Methods (SMP Update 2012) 


ID 

No 

Method 

Mitigation Ratio 

Hard/ 

Softscape 

Requires 

Plan 

Review by 
Agencies 

4A 

Brush Mattress (Brush Layering) 
with Boulder Toe 

1:1 if boulder toe is 
vegetated 

1.5:1 if boulder toe is not 
vegetated 

Vegetated: Hybrid 
Not Vegetated: 
Hard 

No 

4B 

Brush Mattress (Brush Layering) 
with Log Toe 

1:1 

Soft 

No 

5 

Surface Matting (Erosion Mats) 

1:1 

Soft 

No 

5A 

Surface Matting (Erosion Mats) with 
Boulder Toe 

1:1 if boulder toe is 
vegetated 

1.5:1 if boulder toe is not 
vegetated 

Vegetated: Hybrid 
Not Vegetated: 
Hard 

No 

5B 

Surface Matting (Erosion Mats) with 
Log Toe 

1:1 

Soft 

No 

6 

Add Rock to Invert 

1:1 

Hybrid 

No 

6 A 

Rock Cross Vanes 

1:1 

Hybrid 

No 

6B 

Root Wads and Boulders 

1:1 

Hybrid 

No 

6C 

Live Log Crib Walls 

1:1 

Soft 

No 

6D 

Log Revetment 

1:1 

Hybrid 

No 

7 

Cellular Confinement System 

2:1 

Hard 

Yes 

8 

Rock Blanket 

2:1 

Hard 

Yes 

8A 

Boulder Revetment 

2:1 

Hard 

Yes 

8B 

Boulder Revetment with Soil and 
Vegetation 

1:1 

Hybrid 

Yes 

9 

Articulated Concrete Blocks 

3:1 

Hard 

Yes 

9 A 

Articulated Concrete Blocks with 
Planted Areas 

2:1 

Hard 

Yes 

10 

Concrete Crib Walls 

3:1 

Hard 

Yes 

11 

Sacked Concrete 

3:1 

Hard 

Yes 

12 

Gunite Slope Protection 

3:1 

Hard 

Yes 

13 

Earth with Rock Toe on Grass Lined 
Channels 1 

2:l 2 None if rock is below 
bankfull depth, and 
includes some element of 
instream complexity. 

For areas above bankfull 
depth, use mitigation 
ratios as specified in ID 
Nos.l thru 12 above. 

Soft/Hybrid 

No 


1 Grass lined channels are those where grass is the predominant or sole vegetation, and that contain no significant 
riparian structure. The NPW submittal will include photographs and descriptions to justify use of this line item. 

2 None if rock is below bankfull depth and includes some element of instream complexity. 

Source: Data compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-16 


December 2011 
Project 10.005 



2. Project Description 


Through the SMP, SCVWD may implement stream bank stabilization activities when the 
problem: causes or could cause significant damage to SCVWD property and/or adjacent 
property; or is a public safety concern. Additional benefits of stabilizing eroding stream 
banks include reducing instream sedimentation, and protecting water quality and other 
beneficial uses such as riparian habitat and recreation. 

As described in the SMP Manual, sites with eroding or destabilized banks are evaluated for 
their local on-site soil conditions, slope stability, channel position, and geomorphic 
processes. An overall assessment is performed to determine the most appropriate 
treatment to stabilize the bank, with consideration of habitat, species use, and other site 
beneficial uses. Based on the condition assessment, the SCVWD design engineer will 
develop a treatment approach that stabilizes the streambank while trying to minimize the 
use of hardscape. Depending on work site conditions and hydraulic forces, the design 
engineer may favor the use of hardscape elements over softscape treatments if there is an 
increased risk for potential failure of the softscape treatments over the longer-term. 

2.2.2 Sediment Removal 

Sediment removal is the act of mechanically removing sediment deposited within a flood 
protection channel. Sediment removal is required when accumulated sediment reduces a 
channel's flow conveyance capacity, prevents facilities or appurtenant structures from 
functioning as intended, or impedes fish passage and access to fish ladders. Sediment is 
removed from SCVWD facilities to assist a channel to convey flow and minimize flood 
hazard, according to the existing channel design. Sediment removal under the SMP Update 
would not include increasing a channel's flow conveyance capacity beyond the as-built 
design. Sediment removal activities may occur along creeks, canals or at stream gauges. 

Sediment removed from SCVWD channels and facilities would be assessed according to the 
appropriate Sediment Characterization Plan established by the RWQCBs. These 
characterization plans would be used to determine the physical and chemical properties of 
the removed sediment using continuous core, discrete sampling, and residual sampling 
methods. Collected sediment that met wetland reuse criteria area could be transferred to 
the south Bay Pond A8 to support tidal habitat restoration efforts at the pond. Sediment that 
did not meet these standards but met standards for landfill disposal would be disposed at a 
local landfill. Sediment that exceeded hazardous waste criteria would be disposed at an 
appropriate hazardous waste facility (e.g., Kettleman Hills hazardous waste landfill]. Pond 
A8 is anticipated to have sufficient capacity for sediment disposal for the next 2-5 years. 
Additional ponds, including ponds A5, Al, A2W, and A9 have been identified as potentially 
suitable long-term sediment reuse locations. SCVWD also may add other upland or aquatic 
sites to its disposal options. Potential upland sites include the abandoned quarry pond next 
to the Coyote Parkway site, as well as the U.S. Fish and Wildlife Service refuge at Bair Island 
and Phase 2 of the South Bay Salt Pond restoration effort. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-17 


December 2011 
Project 10.005 



2. Project Description 


Sediment removal is a projected work activity. However, as discussed above, decadal 
projections may not reflect the actual maintenance work conducted. Annual sediment 
removal needs would vary, depending on yearly climate and hydrologic conditions. Since 
2002, annual sediment removal volumes have ranged from a minimum of 8,845 cubic yards 
(cy) in 2008 to a maximum of 96,240 cy in 2006 (see Table 2-5], 


Table 2-5. Actual Sediment Removal Work, 2002-2009 



New Work 

Repeated Work 

Sediment 

Annual 


Length (feet) 

Length (feet) 

Removed (cy) 

Precipitation (in) 


Santa Clara Basin 


2002 

36,664 

0 

51,368 

12.98 

2003 

32,946 

4,608 

85,504 

13.62 

2004 

29,205 

30,559 

35,899 

15.10 

2005 

9,170 

45,315 

39,420 

22.80 

2006 

10,199 

22,238 

95,379 

20.42 

2007 

17,989 

13,027 

33,523 

8.38 

2008 

7,229 

5,245 

8,205 

10.71 

2009 

5,512 

5,294 

14,720 

13.83 

Total 

148,914 feet 
(28.20 miles) 

126,286 feet 
(23.92miles) 

364,018 
cubic yards 



Pajaro Basin 


2002 

2,532 

0 

751 

17.36 

2003 

0 

0 

0 

15.93 

2004 

2,853 

0 

1,765 

19.66 

2005 

13,161 

0 

2,664 

24.95 

2006 

1,760 

0 

861 

18.45 

2007 

0 

0 

0 

5.84 

2008 

600 

0 

640 

14.62 

2009 

903 

0 

594 

20.31 

Total 

21,809 feet 
(4.13 miles) 

- 

7,274 

cubic yards 



Source: Data compiled by Horizon Water and Environment in 2011 


As summarized in Table 2-6, over the next 10 years, estimated sediment removal activities 
may include 43 miles of creeks and canals in the Project Area, with approximately 35.4 
miles in the Santa Clara Basin and 7.4 miles in the Pajaro River Basin. Table 2-6 also 
identifies how much of the work estimated for 2012-2022 would be located in "new" 
channel areas (i.e., areas where work was not previously projected for the 2002-2012 
period in the existing SMP). For 2012-2022, about 19 miles of new channel areas are 
projected to have sediment removal work not included in the original program. For 
example, the Guadalupe Watershed will contain over 8 miles of these new work areas. 
However, as shown in the fourth column of Table 2-6, about 15 miles of channel area that 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-18 


December 2011 
Project 10.005 




2. Project Description 


were included in the existing SMP projection for the 2002-2012 work period are no longer 
included in the current projections for the coming decade of work. For example, the West 
Valley Watershed would decrease in sediment removal activities by over 8 miles. Thus, as a 
program, the SMP Update would gain about 4 miles of net additional projected sediment 
removal activities. 

Figures 2-14 through 2-18 (provided at the end of this chapter] are maps that show past 
and future projected sediment removal activities for the primary watersheds of the Project 
Area. More specifically, in Figures 2-14 through 2-18, sediment removal work that was 
projected for the first decade of the SMP [2002-2012] is shown in red. The areas shown in 
goldenrod are reaches where maintenance work was projected for the original decade 
2002-2012 that also has been projected for the next decade. Finally, the areas shown in 
blue are reaches where new work areas have been projected for the 2012-2022 
maintenance period. 


Table 2-6. Projected Sediment Removal Work, 2012-2022 


Watershed 

2012-2022 

Total Projected 
Sediment Removal 
(miles)* 

New Work Areas 
for 2012-2022 
(miles) 

Work Areas from 
2002-2012 

Not Projected for 
2012-2022 (miles) 

Santa Clara Basin 


Lower Peninsula 

3.9 

0.7 

2.6 

West Valley 

3.8 

0.9 

8.3 

Guadalupe 

11 

8.7 

0 

Coyote 

16.7 

5.9 

0.7 

Pajaro Basin 


Pajaro 

7.4 

3.1 

3.5 

Total 

42.8 miles 

19.3 miles 

15.1 miles 


Source: Data compiled by Horizon Water and Environment in 2011 


2.2.3 Vegetation Management 

Similar to sediment removal activities, vegetation management activities are intended to 
maintain the hydraulic conveyance and flood safety functions of SCVWD's channels. 
Vegetation maintenance would seek to trim, thin, or remove vegetation that was causing 
flow blockages or significantly increasing hydraulic roughness and thereby reducing 
channel conveyance capacity. Vegetation management methods would include pruning, 
hand or mechanical removal, herbicide application, mowing, discing, flaming, and grazing. 
These methods are described in detail in the SMP Manual. Vegetation management activities 
may occur along creeks, canals or at stream gauges. Protective measures associated with 
these approaches are described in the BMP Listings (Table 2-12], provided at end of this 
chapter. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-19 


December 2011 
Project 10.005 



2. Project Description 


Certain types of vegetation management work (hand removal, herbicide, pruning, mowing, 
and discing] are projected activities as shown in Table 2-7. As defined in the projections, 
vegetation management may occur from the creek center to the outer edge of SCVWD 
property line/SCVWD management area. Other types of vegetation management (e.g., 
flaming and grazing] would be performed on an as-needed basis along any creek within the 
Project Area where SCVWD has fee title or easement. Tree removals may occur on a site- 
specific basis, per the criteria and mitigation described in the SMP Manual. 


Table 2-7. Projected Vegetation Management Work Type by Watershed 


Watershed 

Hand 

Removal 

(miles) 

Herbicide 

(miles) 

Pruning 

(miles) 

Mowing 

(miles) 

Discing 

(miles) 

Santa Clara Basin 

Lower Peninsula 

2.5 

47.8 

22.7 

3.8 

0 

West Valley 

3.2 

146 

61.7 

32.6 

0 

Guadalupe 

6.9 

277.7 

211.6 

146.8 

.4 

Coyote 

88.6 

213.4 

159.5 

58.3 

.5 


Pajaro Basin 


Pajaro 

49.7 

162 

156.6 

45.9 

.9 

Total 

150.9 miles 

846.9 miles 

612.1miles 

287.4miles 

1.8 miles 


Note: 

Values do not account for overlapping work areas. 

Source: Data compiled by Horizon Water and Environment in 2011 


SCVWD's preference is to first thin or prune trees before considering tree removal. 
However, when tree removal is necessary, SCVWD prioritizes retaining native trees in place 
of non-native species. In general, the program includes the removal of trees and shrubs less 
than or equal to 12 inches diameter at breast height [dbh]. Chapter 2 of the SMP Manual 
describes the District's vegetation management and tree removal activities in detail. 

Several maps, provided at the end of this chapter, describe the location of vegetation 
maintenance activities within the primary watersheds of the SMP. Hand removal, pruning, 
and mowing vegetation management activities that occur below the bankfull elevation 
("instream activities"] are shown in Figures 2-19 through 2-23. Similar to the sediment 
removal maps, the three colors on the map indicate locations for: 

■ projected activities for the first decade of the SMP, 2002-2012 (shown in red]; 

■ projected activities for both the first decade (2002-2012] and second decade 
(2012-2022] of the stream maintenance program (shown in goldenrod]; and 

■ projected activities for only the SMP Update, 2012-2022 (shown in blue as new 
maintenance areas]. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-20 


December 2011 
Project 10.005 



2. Project Description 


Figures 2-24 through 2-28 show the location of hand removal, pruning, mowing, and discing 
vegetation activities that occur above the bankfull elevation in the channel ("non-instream"] 
and are differentiated according to the first or second decade of the SMP, using the same 
three-color system as in the other maps. 

Figures 2-29 through 2-33 include maps that show where instream (below bankfull 
elevations] herbicide application is projected to be applied. Figures 2-34 through 2-38 show 
where non-instream herbicide application (above bankfull elevation] is projected for the 
SMP Update. Because most of the Project Area channels have maintenance road access from 
either side of the channel (see Figures 2-8 and 2-13], vegetation maintenance requiring 
large mechanized equipment typically would occur from the top-of-bank access road and 
the upper bank/bench zone. Large mechanized equipment would not be used to cross an 
active/wet stream channel. Vegetation management occurring in mid-channel areas that 
are separated by active wet creeks would only be conducted with hand-held tools 
(including mechanized hand-held tools], to prevent the need of crossing an active wet 
stream course with large mechanized equipment; although small trucks may need to cross 
wetted areas for creek access. 

2.2.4 Management of Animal Conflicts 

In the Project Area, animals can damage SCVWD channels, facilities, and infrastructure. The 
stability of banks and levees may be reduced as a result of animal burrowing, foraging on 
mitigation sites, and interfering with work activities. Management of animal conflicts refers 
to the use of avoidance tactics, biological control, site alterations, habitat alteration, and 
lethal control to reduce conflicts between SCVWD facilities and local species. These control 
methods are described in the Management of Animal Conflicts chapter of the SMP Manual 
(see Appendix A], Animal conflict management can occur year-round, though the selected 
control methods are dependent on the site conditions, animal specific life cycles, and 
applicable regulatory permits. 

Although routine, the extent and specific locations for animal conflict management are 
generally not known in advance of the conflict itself. As such, animal conflict management 
activities are not projected, with the exception of rodent control activities on designated 
levee reaches. Rodent control activities are estimated to occur on approximately 115 miles 
of creeks and canals in the Santa Clara Basin and approximately 15 miles in the Pajaro Basin 
annually (whereby each bank is counted separately]. 

2.2.5 Minor Maintenance 

Minor maintenance activities would be performed to repair and maintain SCVWD facility 
functions. Minor maintenance activities may occur along creeks, canals or at existing stream 
gauges. Minor activities are small in size and have limited potential to impact environmental 
resources. A minor activity is defined as an activity that results in removing less than 0.05 
acres (2,178 square feet] of wetland or riparian vegetation. The minimum size for any 
minor vegetation work to be notified in SCVWD's NPW is 0.01 acres (436 square feet] per 
project, which includes any vegetation work necessary for access or staging. 

Minor maintenance activities proposed under the SMP Update would include: 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-21 


December 2011 
Project 10.005 



2. Project Description 


■ cleaning and minor sediment removal at outfalls, culverts, flap gates, tide gates, 
inlets, grade control structures, fish ladders, and fish screens (limited to 50 cy]; 

■ minor in-channel (or canal] sediment removal (less than 10 cy]; 

■ trash and debris removal; 

■ repair and installation of fences and gates; 

■ grading and other repairs to restore the original contour of existing maintenance 
roads; 

■ grading small areas without vegetation above stream banks to improve drainage 
and reduce erosion; 

■ repair of structures with substantially similar materials within approximately the 
same footprint (i.e., replacement of concrete linings, culverts, pipes, valves]; 

■ graffiti removal; 

■ installation and on-going maintenance of mitigation and landscape sites (including 
irrigation, weed control, and replanting of dead or declining individual plants until 
success criteria were met]; 

■ removal of obstructions at structures to maintain function (i.e., bridges, stream flow 
measuring stations, box culverts, storm drain outfalls and drop structures]; and 

■ stream gauge maintenance including stilling well cleaning, painting of gauge house, 
replacing/adding antenna or solar panels to existing structures, replacing 
instrumentation, cableway repair, weir cleaning of algae and debris, and unburying 
staff markers/orifice/communication pipes. 

Minor maintenance activities are not projected and may occur anywhere within the Project 
Area. The minimum reporting size for any minor vegetation work is 0.01 acres per project. 
Yearly minor maintenance activities would be limited to less than 0.2 acres of wetland or 
riparian vegetation impact per year. Similarly, cumulative minor maintenance activities 
would be limited to 2 acres total wetland or riparian vegetation impact over the 10-year 
planning period. 

2.2.6 Canal Maintenance 

The SMP Update would include routine and periodic maintenance conducted by SCVWD on 
its canals. The location of SCVWD canals is shown in Figure 2-39, and representative photos 
are provided in Figure 2-40. Unlike the streams and flood protection channels that are the 
primary focus of the existing SMP, SCVWD's canals are primarily water supply transport 
facilities, but they do provide additional flood management functions locally. 

Routine canal maintenance may include all of the general work activities discussed above, 
including: sediment removal, vegetation management, management of animal conflicts, 
bank stabilization, and minor maintenance. 

Sediment removal in canals is typically small in scale and localized (generally 10 cy or less 
per occurrence], and is conducted to clear small sediment deposits ("plugs"] where local 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-22 


December 2011 
Project 10.005 



2. Project Description 


sediments have either entered the canal or have been deposited. Canal sediment removal 
activities are generally performed using a small loader from the top of the adjacent canal 
access road. Canal sediment removal may also be conducted using hand tools because of its 
small volume. 



Figure 2-40. The Almaden-Calero Canal 


Sediment removal may occur anywhere along the canals; however, no more than 1,000 cy of 
sediment would be removed per calendar year from all SCVWD canals. 

Vegetation management along the canals would include some periodic herbicide use, inside 
the canals and along the access roads to address weed growth. In the upland margins 
adjacent to the canals, SCVWD would conduct periodic and routine tree hand pruning, hand 
removal, and grass mowing, using the same techniques described above in the Vegetation 
Management section. In general, vegetation management may occur anywhere along or 
within the canals; however, no more than 6 acres of work would be performed in a given 
calendar year. In addition, discing would be restricted to the right bank of Coyote Alamitos 
canal only. 

Additional minor maintenance activities performed along the canals would include minor 
grading of the access road, graffiti removal, fence repair, erosion repairs, management of 
animal conflicts, and bank stabilization activities. Minor structural repairs may include 
repairing a concrete lining, culvert, pipe, valve, weir, instream orifice, or communication 
pipe. These canal maintenance activities, because of their small-scale and uncertain 
location, are not projected activities and may occur anywhere along the canals as needed. 

2.2.7 Activities Not I nc l ud e d in the SMP Update 

The SMP Update would not include the following activities, which are therefore not 
analyzed in this document: 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-23 


December 2011 
Project 10.005 






2. Project Description 


■ work that would increase the designed flood conveyance or water supply capacity of 
a facility; 

■ maintenance work in stream reaches that are above the 1,000-foot elevation 
contour 

■ removal of hazard trees; 

■ maintenance work of dams, reservoirs and other water supply facilities, such as 
pipelines outside of stream corridors, groundwater percolation ponds, and instream 
summer dams; 

■ installation of new or major modification of fish ladders; 

■ work conducted on private property by others; 

■ work performed by other agencies; 

■ other large construction projects or capital improvement projects; 

■ area-wide, intensive maintenance, or rehabilitation of large (greater than 0.05 acre] 
mitigation projects installed as part of SCVWD Capital Improvement Projects (CIPs] 

■ emergency repair work; and 

■ continued implementation of mitigation measures in the existing SMP. 

A situation is considered an emergency if it is a sudden, unexpected occurrence involving a clear 
and imminent danger that demands immediate action to prevent or mitigate loss of or damage to 
life, health, property, or essential public services (Public Resource Code Section 21060.3], Although 
emergency situations will not be covered in the SMP, SCVWD would make every effort to follow the 
guidance provided in the SMP Manual (Appendix A] when implementing activities under 
emergency conditions. 

Large construction projects and CIPs are not considered routine stream maintenance and are not 
addressed through the SMP. Future CIPs will analyze and account for long-term maintenance 
impacts under the CIP's environmental review. 

2.3 Stream Maintenance Process Overview 

2.3.1 Annual Work Sequence 

Annual administration of the SMP Update would occur in three phases (as shown in Figure 
2-41], In the winter and early spring, maintenance needs would be assessed and prioritized, 
the annual maintenance work plan would be developed, and the regulatory agencies would 
be notified through the Notification Notice of Proposed Work (NPW] document. During the 
summer and early fall, maintenance projects would be more specifically planned and 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-24 


December 2011 
Project 10.005 




2. Project Description 


implemented. Toward the end of the year and into the following early winter, the annual 
Post-Construction Report (PCR] would be developed, distributed, and SCVWD staff and 
managers would meet with regulatory partners to review the past year's work. These work 
phases are described in more detail below. 

Phase 1: Annual Maintenance Activity Identification, Development and 
Documentation 

The first phase of the annual work sequence would begin with identifying maintenance 
needs. Maintenance work could be proposed either as part of the annual work plan through 
the NPW submittal, subsequent regulatory notifications/submittals, or as identified 
throughout the year via individual work orders. SCVWD internal work orders would 
provide a description of the project, schedule of implementation, estimated costs, permit 
requirements, and other special conditions. 

For minor maintenance projects, the appropriate resource protection measures and BMPs 
would be identified and work would proceed. For other maintenance activities, a more 
detailed review process would occur and may include site assessment and/or engineering 
evaluations. These activities would be reviewed to verify they were covered under the long¬ 
term regulatory clearances provided in conjunction with the SMP Update. If the work was 
not covered by the SMP Update, the appropriate project development process would be 
followed, and may include individual CEQA review and project-specific regulatory permits 
or clearances. For covered activities, appropriate resource protection measures and BMPs 
would be identified and added to the work order. For maintenance activities requiring 
compensatory mitigation, mitigation would be planned and notified according to Appendix 
C (2012-2022 SMP Update Mitigation Approach Memorandum] and summarized in Section 
2.4.3 below. Pre-work meetings would be held with appropriate SCVWD staff to discuss 
site-specific requirements, environmental constraints, and BMPs. 

Phase 2: Implementation of Annual Routine Stream Maintenance Work 

Maintenance activities would be implemented during the relevant work season (as 
described below] or as described in the work order. Specific maintenance steps and 
methods are described in more detail below. In addition, direct field monitoring of 
maintenance work would occur for both sediment removal and bank repair activities. This 
would be done so that work would be conducted as described in the annual NPW. Field 
monitoring would include inspections of BMPs so that they would be effective in preventing 
adverse impacts to water quality and stream habitats. 

Maintenance Timing 

Work windows for sediment removal, instream vegetation and herbicide application, and 
bank stabilization generally would be conducted between June 15 and October 15. 
However, if the fall season remained dry, work could continue until the first significant 
rainfall event occurred. A significant rainfall event is defined as local rainfall of 0.5 inches or 
greater within the watershed over a 24-hour period. The following precipitation gages are 
used to determine maintenance work allowance. Each SMP watershed has a target rain gage 
to assess rainfall conditions and to determine if a significant rain event has occurred. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-25 


December 2011 
Project 10.005 



2. Project Description 


■ Lower Peninsula Watershed (station located in the City of Mountain View 
Corporation Yard] 

■ West Valley Watershed (station located at Santa Clara County West Yard 
Maintenance facility] 

■ Guadalupe Watershed (station located near the City of San Jose, Office of Emergency 
Services] 

■ Coyote Watershed ( Penitencia Water Treatment Plant, station located at Anderson 
Dam.] 

* Pajaro Watershed f Church Ave percolation ponds, station located in Morgan Hill] 

Even if no significant rainfall occurred, no instream work (excluding hand pruning and hand 
removal in non-steelhead streams] would continue later than December 31. 

SCVWD also relies on weather forecasts to prepare for situations when significant rains are 
anticipated. After October 15, 72-hour look-ahead weather forecasts from the National 
Weather Service (or local vendor such as the Western Weather Group] would be consulted. 
If a significant rainfall was forecast within the 72-hour forecast window, maintenance work 
that may result in sediment runoff to the stream would be stopped, to allow adequate time 
to complete erosion control measures. 

In general, permits issued by regulatory agencies for the SMP and/or mitigation 
requirements stemming from the CEQA analysis may place additional limitations on work 
types and windows; these would be verified and incorporated into the Proposed Project 
implementation as applicable. 

Other activity-specific requirements related to work windows would include: 

■ Bank Stabilization: 

- Projects that w e r e mor e than 50 p e rc e nt compl e t e on Octob e r 15 may continue 
until the approved date stated below completion or until the first 3-day forecast 
that includeds significant rainfall. 

- In Creeks Supporting Anadromous Fish 

o An extended work window may occur until October 31 st for bank 
stabilization projects that will be 50% complete by October 15 th . 

- In Creeks Not Supporting Anadromous Fish 

o An extended work window may occur until November 30 th for projects 
that will be 50% complete by October 15 th or until significant rainfall. 
o An extended work window may occur until November 30 th for new bank 
stabilization projects that will be completed in five f51 days or less, or 
until significant rainfall. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-26 


December 2011 
Project 10.005 



2. Project Description 


- After October 15, all incomplete bank repair projects would be winterized 1 
before the date when the forecast included significant rainfall. 

■ Sediment Removal: 

- Work may occur until December 31. 

- Additional sediment removal work may occur aft e r th e first significant rainfall 
e v e nt — only within Berryessa Creek (0-88+80; 232+70-236+00; 284+30- 
288+00], Lower Silver Creek (Reach 3 between Stations 37+40 and 381+19], 
Thompson Creek (0+00-10+00], Canoas Creek (0+00-390+00], Ross Creek 
(0+00-86+30], Calabazas Creek (35+00-105+00], and San Tomas Aquino Creek 
(80+00-100+00], if clearance was provided through a preconstruction biological 
survey; site conditions were dry; vehicles would not impact roadways; no water 
diversions were used; and work would stop in the event of any rainfall forecast 
3 days in the future ; and e- mail notification of work would b e provid e d to 
r e gulatory ag e nci e s 2 days b e for e start of work . 

- Sites would be maintained in a winterized state during extended work windows. 

- Work may occur after a significant rainfall event but no later than December 31. 

■ Vegetation Management: 

- As a non-ground disturbing activity, instream hand pruning may occur year- 
round except where equipment would need to access the site by crossing a creek 
or otherwise affect water quality, or in steelhead creeks wh e r e th e g e n e ral work 
window would apply to Dec 31 or significant rainfall . As described above, 
mechanized equipment would not cross an active (wet] creek. 

- Upland vegetation activities and all other non-projected non-instream 
maintenance work may occur year-round, weather permitting. Upland 
vegetation activities would include work occurring above the bankfull hinge 
point (see Figure 2-7] to the outer edge of SCVWD management area. 

Bank Stabilization 

As summarized in Table 2-4, the SMP Update would include several bank stabilization 
approaches, ranging from "soft structures" (e.g., willow brush mattresses, log crib walls, and 
pole plantings], to "hard structures" (e.g., concrete, and sacked concrete , and gabions ], or a 
combination of hard and soft structures. Bank stabilization measures that create extensive 
inflexible, impervious channel banks with essentially no revegetation ability or habitat 
opportunities are termed "hard" and the product is called "hardscape." Measures that retain 


1 Winterization is the process to prepare and maintain work sites with the appropriate BMPs to prevent erosion, 
sediment transport, and protect water quality during the rainy season. Winterization occurs on completion of bank 
repairs or on incomplete projects after October 15 and before the forecast of significant rainfall, 0.5 inches or greater 
of local watershed rainfall within 24 hours. Winterization would be completed before the occurrence of such actual 
significant rainfall. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-27 


December 2011 
Project 10.005 



2. Project Description 


natural earthen banks and have higher capacity to support vegetation or habitat are termed 
"soft" and the product is called "softscape." 

Hybrid bank stabilization refers to a combination approach whereby softscape bank 


stabilization aooroaches like live construction, contour wattline, brush mattresses. 

or 

surface erosion matting are combined with a limited amount of rock toe orotection at the 

base of the bank stabilization site. Additional boulders at the toe of the bank treatment 

is 

onlv aDDlied if necessary, if there are hydraulic shear forces affecting the bank site, 

or 

geologic slumping or mass wasting forces affecting the site fbecause of the site's position 

or 


slope] that require the additional presence of mass /rock at the base of the slope. 

SCVWD has committed that no more than half of non-in-kind bank repairs would consist of 
impervious hardscape each year. Bank stabilization also would include preventative 
maintenance to reduce the chances of banks eroding in the future. Refer to the Bank 
Stabilization Methods table in the Bank Stabilization chapter of the SMP Manual for further 
descriptions of each method (see Appendix A}. Equipment used for bank stabilization 
activities may include excavators, bulldozers, and front-end loaders for bank grading and 
earth-moving activities. Staging typically would occur on adjacent access roads. Soil and 
other repair materials typically would be staged in areas that were previously disturbed 
(i.e., service roads, turn-outs, etc]. In some cases, bank stabilization projects may require 
the installation of temporary roads and ramps to access the work site. Where tree pruning 
would not provide adequate clearance for maintenance vehicles and heavy equipment, 
SCVWD would make an effort to select an access route that would avoid mature, native 
trees. Where trees may have to be removed, SCVWD would target non-native trees for 
removal. Removal of large branches from mature trees for equipment access would be 
evaluated carefully and avoided whenever possible. The average duration of bank 
stabilization work is 10 working days per site. 

Sediment Removal 

Sediment may be removed by excavators, grade-alls, draglines, and/or loaders. Temporary 
dams, pipes, and existing overflow channels would be used if water needed to be bypassed 
around the site during work. Sediment removed from the channel typically would be placed 
in 10- or 20-cy dump trucks, and prepared for off-site hauling and disposal. Stockpiling of 
sediment to allow for drying before disposal only would be done when sufficient space 
would allow the temporary piling of material; however, this would not be typical. The 
average duration of a sediment removal project would be 10 days, although it could last up 
to several weeks, depending on the size of the project. Further details regarding the specific 
methods used for sediment removal are provided in Appendix A. 

Vegetation Management 

Vegetation management techniques would include hand removal, using small tools and 
hand-held equipment (chainsaws, weed-eaters, flamers], mechanical removal using heavy 
equipment, herbicide application, and grazing. Heavy equipment used for vegetation 
removal may include a disc attachment on a tiller to clear aboveground herbaceous plants 
on the upland parcels outside of stream banks; flail mowers to cut weeds and other 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-28 


December 2011 
Project 10.005 



2. Project Description 


vegetation on the inside slope of some levees or stream banks; or a backhoe or rubber- 
tracked excavator, used for removing material from the channel. 

New techniques described in the 2012 SMP Manual (Appendix A] would include grazing and 
the use of flamers to manage vegetation. In limited circumstances, SCVWD may use various 
domestic animals to provide non-specific weed control. Such animals may include sheep, 
goats, or other appropriate species. Larger scale grazing by cattle is normally not 
appropriate for SCVWD facilities. Flaming would involve the use of a hand-held, propane gas 
powered flamer to control weed seedlings. 

Herbicide application in upland areas typically would be sprayed from a truck-mounted rig 
or applied using a controlled drop applicator. Spray trucks would be used to apply 
herbicides to areas such as maintenance roads. Herbicides may be selectively sprayed 
instream following appropriate biological surveys and clearances. Only herbicides and 
surfactants approved for aquatic use by the USEPA and registered for use by the California 
Department of Pesticide Regulation would be used for SCVWD's aquatic vegetation control 
work. 

The SMP Update includes an expanded list of herbicide types and a broader area of 
application. For example, application of herbicides in the Pajaro River watershed was not 
included in the existing 2002 SMP Manual and FEIR. This restriction was self-imposed and 
later was formalized in some of the regulatory permits issued for the SMP in 2002. Use of 
surfactants also was limited under the original program. 

The Proposed Project would enable herbicide use within the Pajaro River watershed and 
incorporate surfactants under restricted conditions as an application aid. Additional 
application adjustments would include: a longer work window (see above]; application in 
upland areas; and application in sensitive species habitat under certain restrictions. See 
Table 2-11 at the end of this chapter for a comparison between existing SMP (2002-2012] 
and the SMP Update (2012-2022] approaches. 

Once vegetation management was complete, a portion of the woody green waste would be 
chipped for mulch and stored for later use at SCVWD property, while the remainder would 
be transferred to a composting landfill. 

Management of Animal Conflicts 

Management of animal conflicts generally would be conducted with the use of hand-placed 
materials using small tools and hand-held equipment. This would include establishing 
buffers and biological repellants, trapping, as well as lethal baiting and fumigant 
applications (see Appendix A for more details on methods]. Heavy equipment may be used 
to modify habitat conditions and reduce or eliminate burrowing animals through surface 
compaction, filling of burrows with slurry, and tilling areas to destroy food sources. All 
lethal control methods would be designed to comply with the County Agriculture 
Commission requirements and would be implemented using BMPs that would be designed 
to avoid or minimize effects on special-status species. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-29 


December 2011 
Project 10.005 



2. Project Description 


Minor Maintenance and Canal Maintenance 

In general, Minor Maintenance and Canal Maintenance would include activities already 
described under the previous four categories. Further information regarding their 
implementation can be found in Appendix A. 

Phase 3: Annual Reporting 

At the conclusion of each year's maintenance season, a Post-Construction Report (PCR] 
would be developed and submitted to the appropriate resource agencies. This report would 
include a summary of the year's maintenance projects, describing what activities occurred 
and where, a description and confirmation of the restoration and mitigation activities 
implemented, and other SMP updates as necessary. 

Annual Program Review 

Following the submittal of the PCR, resource agency staff would be invited to meet with 
SCVWD staff for an annual “lessons learned meeting," to be held in February or March of 
each year, to evaluate the effectiveness of both resource protection and maintenance 
methods used in the preceding construction season. The information discussed at these 
annual lessons learned meetings would be used to adaptively manage the BMPs and SMP 
processes to improve SMP effectiveness. 

2.4 Programmatic Impact Avoidance, Minimization, and 
Compensatory Mitigation 

A three-part sequence would occurs so that Proposed Project impacts would be avoided, 
minimized, or addressed through compensatory mitigation. First, the SMP Update itself has 
several built-in or internal restrictions and protocols to avoid or minimize impacts by 
limiting how and where maintenance could occur. Second, the operational implementation 
of maintenance activities would be required to adhere to specific BMPs. Thirdly, residual 
impacts remaining after these two impact avoidance and minimization efforts would be 
addressed through compensatory mitigation. These three approaches to address potential 
Proposed Project impacts are further described next. 

2.4.1 Programmatic Impact Avoidance and Minimization 

The Proposed Project would incorporate the following overarching principles to protect 
natural resources and guide decision-making for stream maintenance activities and 
projects. Proposed Project BMPs (discussed further below] were developed to be consistent 
with these principles. 

Principle 1: SCVWD will implement all routine stream maintenance activities 
according to the process and protocols established in the SMP Update. 

Principle 2: Decisions regarding the necessity of routine sediment removal and 
vegetation management activities (to restore channel flow capacities] 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-30 


December 2011 
Project 10.005 



2. Project Description 


will be made following the thresholds and standards provided in the 
District's Maintenance Guidelines and Asset Management Program. 

Principle 3: SCVWD will implement measures to avoid and minimize impacts to 
native species and habitat. 

Principle 4: All maintenance activities will be performed in a manner that has the 
least impact to the natural flora, fauna, and aquatic resources while 
meeting SMP Update objectives. 

Supporting these SMP principles, the following measures and protocols would be applied by 
SCVWD so that the work would be effective and also would avoid or minimize potential 
environmental impacts: 

■ No work above 1,000-foot contour level. This elevational boundary would limit the 
extent of the SMP and prevent maintenance work in the higher watershed lands. 

■ Identifying the Minimum Maintenance Need: SCVWD would identify and evaluate 
maintenance needs using the standards and thresholds in the Maintenance 
Guidelines and Asset Management Program. These guidelines are based on the 
engineered design of the channel and outline the level of maintenance required to 
maintain adequate flood protection capacity in the streams and canals within 
SCVWD's jurisdiction. This measure would minimize unnecessary intervention in 
stream processes and restrict maintenance to only necessary and appropriate 
activities. 

■ Consideration of Existing Channel Features in Analysis and Design: SCVWD would 
attempt to retain the functions of instream habitat features such as low-flow 
channels and pools after sediment removal in areas used for migration by 
salmonids. In such areas, the geomorphic functions of existing channel features 
would be incorporated into the project design approach, as feasible, to restore 
instream habitat functions. Similarly, SCVWD would consider the hydraulic 
influences upstream and downstream of bank stabilization sites to address potential 
stream velocity and erosion effects. Bank stabilization projects would be designed to 
minimize impacts to the stream channel. 

2.4.2 Best Management Practices 

The maintenance activities would incorporate a range of measures to minimize undesired 
effects on the environment and to implement the SMP principles described above. BMPs 
specifically created for the SMP Update encompass the range of proposed maintenance 
activities and the environmental conditions of the Project Area. The BMPs for the SMP 
Update are listed in Table 2-12 at the end of this chapter. These BMPs include general BMPs 
that would apply to all work, as well as activity-specific BMPs designed to address 
anticipated effects of certain work activities or particular types of resources. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-31 


December 2011 
Project 10.005 



2. Project Description 


2.4.3 Compensatory Mitigation 1 

SMP Mitigation Program under the Existing 2002 SMP 

SMP mitigation measures were developed in 2002 to compensate for anticipated impacts 
caused by SMP activities. Mitigation for sediment removal and vegetation management was 
based on a comprehensive accounting in 2002 of the potential impacts from maintenance 
activities on instream wetlands, tidal wetlands, riparian vegetation, and other sensitive 
habitats in the program area. Table 2-8 summarizes the existing mitigation requirements 
for ongoing SMP activities. The SMP mitigation program includes land acquisition, habitat 
protection, and wetland restoration/creation , and invasiv e sp e ci e s control activiti e s to 
mitigate for maintenance activities. 

An important aspect to the original mitigation approach was that the "programmatic" or "up 
front" mitigation was calculated based on the maximum work projections. The 
programmatic mitigation included coverage for repeat maintenance work at sites in 
perpetuity. Impacts from other non-projected maintenance activities such as bank 
stabilization projects are mitigated on an "as-needed" basis using defined mitigation ratios 
as maintenance projects occur. 

As shown in Table 2-8, to date not all of the SMP’s mitigation requirements have been met. 
The District is committed to completing all remaining mitigation requirements. Appendix A 
of the Mitigation Approach Memorandum fwhich is included in the DSEIR as Appendix Cl 
includes a letter from the District to San Francisco Bay RWOCB that describes the current 
status of the SMP mitigation program and presents a plan to meet all of the District's SMP 
mitigation requirements identified in the 2002 SMP and the associated permits for the 
2002-2012 program period. The District Board has recently approved the purchase of a 
property fknown as the "Castle & Cooke property"! The District continues to pursue land 
acquisition opportunities for Stream and Watershed Protection. In addition, a propos e d 
proj e ct to r e stor e w e tlands at Laguna S e ca is curr e ntly und e r t e chnical r e vi e w. If f e asibl e , 
this proj e ct could provid e som e or all of th e r e maining n ee d e d w e tland mitigation cr e dit. 

The mitigation requirements shown in Table 2-8 were established in 2002 based on the 
maximum SMP work projections at that time. The actual amount of sediment removal work 
conducted during the 2002-2012, as shown in Table 2-1, was 371,292 cy, which is about 47 
percent of the total sediment removal volume of 795,600 cy projected in 2002. Or, in terms 
of length, 32.3 miles of sediment removal have been conducted to date, about 56 percent of 
the 2002 projected length of 58 miles. Completed vegetation management activities since 
2002 have been more consistent with the original work projections. 


1 While the mitigation program is not technically part of the Proposed Project, it is summarized in this chapter for 
clarity and because the impacts of the mitigation program were considered in the environmental analysis in this 
DSEIR. A more complete description of the mitigation program is presented in Appendix C, and mitigation 
measures for significant impacts have been included in the impact analysis. These mitigation measures would direct 
the District to implement the mitigation program, and each mitigation measure describes the manner in which it 
would be implemented to addresses a significant impact. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-32 


December 2011 
Project 10.005 



2. Project Description 


As shown in Table 2-8, 30 acres of required tidal wetland mitigation for the program have 
been completed. This is approximately 21 acres greater than the mitigation that would have 
been required based on the area of tidal wetland impacted to date. The District is proposing 
to use the 21+ acres already provided as mitigation as credit toward future tidal habitat 
impacts that are not yet identified or accounted for. The smooth cordgrass control 
mitigation component compensates for the time-lag between immediate impacts to tidal 
wetlands from SMP activities and the delay in the creation of a functional tidal wetland 
mitigation project. The smooth cordgrass control mitigation requirement is complete. 
Freshwater wetland mitigation in the Santa Clara Basin is not yet complete, but in the 
Pajaro Basin, freshwater wetland impacts have been mitigated fully. As described above, 
SCVWD is committed to completing the mitigation requirements assigned for the 2002 
program work projections, for which the 2002 projected areas will have mitigated for work 
activity impacts in perpetuity. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-33 


December 2011 
Project 10.005 



2. Project Description 


Table 2-8. 2002 SMP Mitigation Program 


Mitigation Type 

Mitigation Purpose 

Mitigation Requirement 

Mitigation 
Completed to Date 

Percent of 
Requirement 
Completed* 

Tidal Wetland Restoration 

Restore Bay salt ponds to tidal 
marsh conditions, provides 
mitigation for tidal wetland 
impacts 

30 acres 

30 acres 

100% 

Freshwater Wetland 

Creation/Restoration 

Convert or restore areas to 
seasonal or perennial wetlands, 
provides mitigation for non-tidal 
wetland impacts 

10-acre Santa Clara Basin 
4-acre Pajaro Basin 

7-acre Santa Clara Basin 

4-acre Pajaro Basin 

70% Santa Clara Basin 
100% Pajaro Basin 

Stream and Watershed 
Protection 

Preserve, protect, and improve 
streams and associated 
watersheds, provides mitigation 
for non-tidal wetland and CRLF 
impacts 

Freshwater wetland habitat: 

■ 820-1080 acres acquired 
(81-acre credit) for Santa 
Clara Basin 

■ 11-acre credit for Pajaro 
Basin 

■ CRLF Habitat—108-acre 
credit District-wide 

Freshwater wetland habitat: 

■ 10-acre credit (125 ac 
total) for Santa Clara 

Basin 

■ 11-acre credit (138 ac 
total) for Pajaro Basin 

■ CRLF Habitat - 56-acre 
credit Santa Clara Basin 

■ 12% Santa Clara 
Basin 

■ 100% Pajaro Basin 

■ 52% CRLF Habitat 

Giant reed (Arundo donax) 
Control 

Control giant reed outbreaks; 
map, revegetate, educate, and 
coordinate reed control efforts in 
the county 

125 ac District-wide 

116 acres District-wide 

93% 

Invasive Smooth Cordgrass 
Control ( Spartina a Item if lorn) 

Control Invasive Cordgrass along 
tidal shorelines, provides 
mitigation for time lag until tidal 
wetland mitigation is established 

Up to 10 acres in tidal areas 

10 acres 

100% 


* With the purchase of the Castle & Cooke property, some of the mitigation requirements not yet complete as shown above would be completed. Also, this 
status summary does not include achievement of final success criteria at completion of the monitoring period. 

Source: Data compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-34 


December 2011 
Project 10.005 



2. Project Description 


2012 Updates to the 2002 SMP Mitigation Program 

The proposed SMP Update process includes reviewing and revising the existing 
compensatory mitigation package that was established in 2002. The 2002 SMP Mitigation 
Program that covers the original projected activities (sediment removal and vegetation 
management] would remain in place to provide compensatory mitigation in perpetuity for 
the channels identified in the 2002 work projections. The channel reaches shown in red in 
the maps at the end of this chapter (Figures 2-14 through 2-38] have all had their mitigation 
provided for through the original mitigation program. Because the original programmatic 
mitigation was developed to address compensatory mitigation for the 2002 SMP identified 
channels based on full work projections, the mitigation provided for these reaches (shown 
in red and gold colors in the maps] continues in perpetuity. No new significant 
environmental effects or a substantial increase in the severity of previously identified 
significant effects are anticipated under the SMP Update in these locations. 

As described in Appendix C to the DSEIR fMitigation Approach Memorandum! SCVWD 
would provide compensatory mitigation for SMP Update activities requiring mitigation by 
acquiring or protecting appropriate mitigation lands (including populations of special- 
status species, where impacts are to such species! using conservation easements or other 
vehicles as appropriate, or would provide suitable ecological services-based mitigation as 
needed to compensate for annual impacts. SCVWD would identify funding mechanisms to 
support the long-term maintenance and conservation of such mitigation lands and projects. 

The compensatory mitigation program proposed for the SMP Update addresses potential 
impacts anticipated for new work sites that were not included in the original SMP work 
projections and not accounted for in the initial compensatory mitigation package. These 
sites are the blue channel reaches shown in the maps of Figures 2-14 through 2-38. 
Potential residual impacts from maintenance that would require mitigation in new work 
sites are similar in nature to the potential impacts that were identified in the 2002 SMP 
FEIR. Although the existing SMP mitigation would continue to serve as mitigation for the 
original work sites identified in the 2002 SMP, additional mitigation would be required for 
the new work sites. 

The District identified the new work sites based on its understanding of maintenance needs 
for the 10-year period beginning in 2012. However, as observed from 2002 until the 
present, it is highly unlikely that all of the identified potential new sites will have actual 
work conducted. Because of the potential inaccuracy of using projected work estimates 
developed in 2010-2011 as a basis for defining mitigation requirements until 2022, the 
District has adjusted its approach in mitigation requirement identification. The District is 
now using the actual work sites (versus work site projections] as the final basis for 
mitigation requirements in new work sites. The SMP Update projects some "new" 
maintenance activities in previously mitigated areas. The impacts of this "new" work are 
considered to have been mitigated by the previous mitigation program because they are in 
the same work category (e.g., vegetation management]. 

The 2012-2022 maintenance work projections provided in the 2012 SMP Update DSEIR are 
useful estimates of where work would be conducted. The projections represent the 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-35 


December 2011 
Project 10.005 



2. Project Description 


District's best estimate of where work would occur. The work projections are 
"conservative" because work likely would not occur in all of the newly identified reaches 
shown in the maps provided at the end of this chapter. The work projections are a useful 
basis to consider potential programmatic impacts to wetlands and other habitats and 
develop a suitable mitigation approach that can guide the next decade of the program. 

Besides addressing mitigation for these new work sites, the compensatory mitigation 
program has been revised to improve overall mitigation feasibility and quality. A key 
constraint to the original SMP mitigation approach was its emphasis on land acquisition. As 
a result, feasible mitigation was often not available in a manner to support the program's 
needs. For the 2012 SMP Update, a broader suite of suitable mitigation approaches has been 
developed to provide increased flexibility while maintaining high mitigation quality. 

As a result of this revised approach, three two key changes are being made to the existing 
programmatic mitigation program (for sediment removal and vegetation management] for 
the 2012 SMP Update: 

1. Ecologic Services. In addition to land acquisition-based mitigation projects that 
provide mitigation in perpetuity (i.e., mitigate for repeat impacts in the same work 
location], programmatic mitigation for sediment removal and vegetation 
management also would include ecologic services-based mitigation projects for 
individual maintenance projects. These approaches would provide mitigation on a 
"pay as you go" or incremental basis. Ecologic services-type mitigation projects 
would only mitigate for an individual work activity. Service-based "pay as you go" 
mitigation would be identified annually based on the annual maintenance work 
plan, provided in the annual NPW, and verified in the end of year annual PCR. 

2. Project Specific Accounting. Rather than identifying all the necessary mitigation 
areas (acreages] for sediment removal and vegetation management activities "up 
front" in 2012 for the new work sites where maintenance would occur between 
2012 and 2022, mitigation criteria and metrics would be identified by standard unit 
measures (typically acreages]. The specific extent of mitigation required for any 
given year's work will be defined annually when the work areas are precisely 
identified. This annual mitigation analysis will clearly distinguish mitigation 
requirements for new work areas from mitigation already accomplished for work in 
areas projected in 2002. Th e actual mitigation r e quir e m e nt would b e calculat e d 
annually wh e n th e work sit e s w e r e mor e pr e cis e ly d e fin e d. 

S -.— N e w Programmatic Mitigation. In addition to th e mitigation approach e s d e scrib e d 
above, the District would provide additional programmatic habitat mitigation 
through th e instr e am compl e xity and grav e l augm e ntation mitigation programs. 

These two three adjustments to the programmatic mitigation program are further described 
in Appendix C (2012-2022 SMP Update Mitigation Approach Memorandum], The District 
would be able to use "pay as you go" mitigation projects/services to provide incremental 
mitigation annually on an as-needed basis. The District also could continue to purchase 
lands to provide longer-term mitigation needs. In this way, the District would have more 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-36 


December 2011 
Project 10.005 








2. Project Description 


flexibility to pursue suitable mitigation opportunities through either long-term land 
acquisition or annual mitigation project approaches. Mitigation credits from the 2002 SMP 
mitigation program (Stream and Watershed Protection] may potentially be applied to new 
work areas in need of mitigation support. The District would work with the appropriate 
regulatory staff to identify, review, and approve the potential application of existing 
mitigation credit toward new work areas. 

As described above, the location and extent of bank stabilization activities are difficult to 
predict and have never been projected work activities. Since 2002, bank stabilization 
projects that required mitigation have been mitigated using an annual assessment and “pay 
as you go" incremental mitigation process. For bank stabilization projects, identifying 
impacts and necessary mitigation would continue to occur annually, depending on what 
bank work was needed. Bank stabilization treatments and their associated mitigation ratio 
requirements are listed in Table 2-4, and may include programmatic mitigation components 
(instream complexity] as well. 

Table 2-9 summarizes the key attributes of the updated mitigation approach for sediment 
removal and vegetation management activities. Details for these programs are provided in 
Appendix C (2012-2022 SMP Update Mitigation Approach Memorandum], 


Table 2-9. 2012-2022 Mitigation Approach for Sediment Removal and Vegetation 
Management Activities 


Mitigation Component 

Ratio/ 

Metric 

Notes 

Land acquisition (in-kind 
preservation/enhancement] 

3:1 

Mitigation applied in perpetuity 

Land acquisition (in-kind restoration] 

1.5:1 

Mitigation applied in perpetuity 

Land acquisition (watershed lands out of kind] 

8:1 

Mitigation applied in perpetuity 

Invasive plant management program 

1.2:1 

Mitigation assessed and applied annually 

Riparian restoration and planting program 

1.2:1 

Mitigation assessed and applied annually 

Tree plantings for removal of trees less than or 

1:1 

Mitigation ratio determined by tree scoring 

equal to 12 inches dbh 

2:1 

3:1 

protocol provided in the 2012-2022 SMP 
Update Mitigation Approach Memorandum 
(Appendix C of this document], in its 
Appendix B. 

Instream habitat complexity features 

<151:1 

Mitigation can be applied either through a 
number of projects or according to project 
area, using the 115-1:1 ratio 

Gravel augmentation in steelhead creeks 

1:1 

Mitigation option for impacts in steelhead 
creeks due to sediment removal activities 


Source: Data compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-37 


December 2011 
Project 10.005 



2. Project Description 


In addition to the programmatic mitigation described in Table 2-9 for sediment removal 
and vegetation management, mitigation would be provided to compensate for impacts to 
individual special-status species resulting from SMP Update activities. The species for which 
compensatory mitigation would be provided, and the form that this mitigation would take, 
is identified in Section 3.3, Biological Resources and will be further described in pending 
Biological Opinions [BOs] for the 2012 SMP Update to be issued by the National Marine 
Fisheries Service (NMFS] and the U.S. Fish and Wildlife Service UJSFWS 1 as well as the 
Incidental Take Permit that will be issued by the California Department of Fish and Game 
fDFGl . The impact analysis in this document is intended to provide CEQA coverage for all 
mitigation activities under the Proposed Project, to the extent that the mitigation projects 
would not result in any new or more significant impacts than those disclosed in this DSEIR. 

The mitigation approach presented in this DSEIR has been developed to meet the 
requirements of CEQA. However, it is anticipated that the mitigation approach will be 
further refined as part of the programmatic permit renewal process. Therefore, in no case 
would the mitigation program be changed so that it would be less protective of the 
impacted resources in question, compared to the approach presented in this DSEIR. Once 
mitigation requirements have been finalized, SCVWD staff would track and report annual 
and cumulative work quantities to verify compliance with the one-time accounting 
mitigation package. 

2.5 Permits and Approvals 

Several state and federal agencies granted permits and approvals to SCVWD to implement 
the 2002-2012 SMP. These same agencies are working together as the Inter-Agency Work 
Group (IAWG] in an effort to refine the SMP Update and required mitigation, and issue new 
multi-year permits and approvals to authorize SCVWD to continue implementing the SMP 
between 2012 and 2022. As CEQA responsible agencies, state permitting agencies will 
utilize this SEIR (once it is certified] as their CEQA compliance document in issuing permits. 
If applicable, the U.S. Army Corps of Engineers [USACE] will use this SEIR as background 
information for Section 404 permit NEPA compliance, and the USFWS and NMFS will use 
this SEIR as background information for Section 7 consultation with the USACE. A summary 
of agencies, applicable laws/regulations, and existing permits proposed for renewal is 
provided in Table 2-10 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-38 


December 2011 
Project 10.005 



2. Project Description 


Table 2-10. Agency Approvals 


Agency 

Applicable 

Law/Regulations 

Guiding 

Jurisdiction 

Current or Prior Permits or Approvals for Maintenance 

Description 

Original Date 
of Issuance 

Date of 
Expiration 

California 
Department of 

Fish and Game 
(DFG) 

Fish and Game Code 
Section 1602 

Lake and Streambed Alteration 
Agreement, Notification No. 
R3-200-0119 

July 8, 2002 

Dec 31, 

204410 

Lake and Streambed Alteration 
Agreement. Notification No. 
1600-2009-0361-R3 

lan 21. 2011 

Dec 31.2014 

Fish and Game Code 
Section 2081 
(California 
Endangered Species 
Act) 

N/A 

N/A 

N/A 

California State 
Lands 

Commission 

State Lands Act 

Lease of State Lands 

Various 

Various 

NOAA National 
Marine Fisheries 
Service 

Endangered Species 
Act (ESA) Section 7 

Biological Opinion 

AR: 151422-SWR-01-SR-408 

July 3, 2002 

July 15, 2012 

Central Coast 
Regional Water 
Quality Control 
Board 

Porter-Cologne 

Water Quality 

Control Act 

Clean Water Act 
(CWA) Section 401, 
Water Quality 
Certification 

Waste Discharge 

Requirements 

Order No. R3-2002-0008 

March 22, 2002 

March 2012 

San Francisco 

Bay Regional 
Water Quality 
Control Board 

Porter-Cologne 

Water Quality 

Control Act 

CWA Section 401, 
Water Quality 
Certification 

Waste Discharge 

Requirements and Water 

Quality Certification— 

Order No. R2-2002-0028 

Feb 27, 2002 

February 2012 

San Francisco 

Bay 

Conservation 

and 

Development 

Commission 

Federal Coastal 

Zone Management 

Act of 1972 

Permit No. M77-113 

Authorization to conduct work 
in tidal sloughs in Santa Clara 
County 

Feb 8, 1978 

June 1, 2015 

U.S. Army Corps 
of Engineers 
(USACE) 

CWA Section 404 

Rivers and Harbors 
Act of 1899, 

Section 10 

NEPA 

Permit Number 22525S 

August 7, 2002 

July 15, 2012 

U.S. Fish and 

Fish and Wildlife 

Biological Opinion Permit 

July 5, 2002 

July 15, 2012 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-39 


December 2011 
Project 10.005 



2. Project Description 


Table 2-10. Agency Approvals 


Agency 

Applicable 

Law/Regulations 

Guiding 

Jurisdiction 

Current or Prior Permits or Approvals for Maintenance 

Description 

Original Date 
of Issuance 

Date of 
Expiration 

Wildlife Service 

Coordination Act 
Endangered Species 
Act 

Number 22525S 




N/A = Not applicable; the District was not required to obtain a Section 2081 take permit in the 2002 SMP. 
Source: Data compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-40 


December 2011 
Project 10.005 



2. Project Description 


Table 2-11. Comparison of Key Differences between 2002 SMP and 2012 SMP Update 


Description of Activity 2002 SMP 2012 SMP Update 


Bank Stabilization 


Work Window 


Generally between July 1 and October 15, 

50 percent completed project may extend to 
October 30. 


July 1 lune 15 to October 15. Projects may continue until the 
approved date stated below 50 p e rc e nt compl e t e d proj e cts by 
Octob e r 15 may continu e until compl e tion, or until the first 5 - day 
72-hour forecast that includes significant rainfall (greater than 
0.5 inch/24 hours]. 


• In Creeks Supporting Anadromous Fish 

o An extended work window may occur until October 31 st 
for bank stabilization projects that will be 50% complete 
by October 15 th . 

• In Creeks Not Supporting Anadromous Fish 

o An extended work window may occur until November 
30 th for projects that will be 50% complete by October 
15 th or until significant rainfall. 

o An extended work window may occur until November 
30 th for new bank stabilization projects that will be 
completed in five (5] days or less, or until significant 
rainfall. 


Exclusions 


Does not cover certain bank stabilization methods 
in high-quality fish or riparian habitat. 


Preference is for softscape methods. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-41 


December 2011 
Project 10.005 





2. Project Description 


Table 2-11. Comparison of Key Differences between 2002 SMP and 2012 SMP Update 


Description of Activity 

2002 SMP 

2012 SMP Update 

Methods Table 

29 methods (see SMP Manual) 

Methods list revised, 9 methods updated (see below), 7 methods 
eliminated (see Table 2-4): 

• lB-Earth Repair with Buried Rock 

• 2 B- Live construction with Log Toe 

• 3B-Contour Wattling with Log Toe 

• 4B-Brush Mattress (Brush Layering) with Log Toe 

• 5B-Surface Matting (Erosion Mats) with Log Toe 

• 6-Add Rock to Invert 

• 6A-Rock Cross Vanes 

• 6D-Log Revetment 

• 13-Earth with Rock Toe Below OHW 

Agency Review Time for 

Bank Stabilization Designs 

45 days for review and response 

30 days for review and response 

Mitigation Requirements 

Based on stream-side impact mitigation matrix and 
standard success criteria (see BMP 2.4) 

Mitigation will be determined via the Bank Stabilization Methods 
Table and the programmatic mitigation approach for instream 
complexity. 

Success criteria to be determined based on specific site 
conditions reviewed via the Mitigation Feasibility Assessment. 

Winterization 

Required for active instream work sites if 
significant rainfall (greater than 0.5 inch/24hours) 
occurs after October 15. 

Considered to occur upon completion of bank repairs or on 
incomplete projects after October 15 and prior to forecast of 
significant rainfall (greater than 0.5 inch/24hours) 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-42 


December 2011 
Project 10.005 





2. Project Description 


Table 2-11. Comparison of Key Differences between 2002 SMP and 2012 SMP Update 


Description of Activity 2002 SMP 2012 SMP Update 


Management of Animal Conflicts 


General 


Included as part of "Minor Activities.. Incorporated 
rodent control using rodenticide, traps, and smoke 
bombs. Limited detail. 


New section of SMP Manual describing in detail, the management 
of animal conflicts. Now includes: 

• Maintenance of Sanitary Conditions 


• Avoidance 


• Biological control 

• Physical alterations 

• Habitat alterations 


• Non-lethal trapping/relocation; and 


Requirements 


• Lethal control 


BMP 3.21 listing of several requirements including: 


Additional requirements include: 


• No rodenticides or fumigant application near 
salt harvest mouse range, one-half mile of 
burrowing owl locations, or potential range of 
sensitive amphibians 

• Minimization of secondary poisoning impacts 
including carcass clean-up and surveys 


• No rod e nticid e s or fumigant application within the current 
mapped potential range of sensitive amphibians. 

• Specifically designed bait stations to prevent entry of 
California Ttiger ^salamander, California Rred-Llegged Ffrog, 
or Ffoothill ¥yellow-tlegged Ffrog species , or Salt Marsh 
Harv e st Mous e. 


• Live traps will be designed to allow salt marsh harvest mouse 
to enter and exit easily. 

• Minimization of secondary poisoning impacts including clean¬ 
up and disposal of spilled bait 


• A 656-vard buffer will be established around known 

burrowing owl locations where no rodenticides or fumigants 
fincluding smoke bombs') will be used. A 0.5-mile buffer will 
be established around known bald eagle and golden eagle 
nesting locations where no rodenticides will be used. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-43 


December 2011 
Project 10.005 





2. Project Description 


Table 2-11. Comparison of Key Differences between 2002 SMP and 2012 SMP Update 


Description of Activity 

2002 SMP 

2012 SMP Update 

Minor Maintenance | 

Work Activities 

Approximately 12 distinct work activities. 

Updated list of 11 work activities. Pruning/ vegetation control 
and animal control activities are no longer classified as Minor 
Maintenance (included in Vegetation and Animal Conflict 
management instead) 

Definition of Minor 

No size limitations described for clearing and 
minor sediment removal activities 

• Cleaning and minor sediment removal activities at 
facilities/structures are limited to 50 cubic yards 

• Minor sediment removal less than 10 cubic yards per site may 
be removed anywhere instream 

Mitigation/Limitations 

Equivalent area of mitigation provided for annual 
impacts greater than 0.2 acres to wetland and 
riparian vegetation removed by minor work 
activities (or 2 acres for the 10 year program). 

• Less than 0.01 acre not reported 

• .01-.05 accounted 

• 0.2 acre annual max/year 

• 2 acres max per 10-year permit 

• Coverage per compensatory mitigation 

• See Appendix C for a description of mitigation requirements. 

• Minor maintenance requirements for annual impacts less 
than or equal to 0.2 acres per year remain the same. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-44 


December 2011 
Project 10.005 






2. Project Description 


Table 2-11. Comparison of Key Differences between 2002 SMP and 2012 SMP Update 

Description of Activity 2002 SMP 


Sediment Removal 


Work Window 


Instream work limited to June 15-0ctober 30 or 
first significant rainfall after October 15 (greater 
than 0.5 inch/24 hours], whichever occurs first. 


2012 SMP Update 


June 15-October 15, with extended work window under the 
following conditions: 

* Creeks Supporting Anadromous Fish: 

An extended work window may occur from October 15 
through October 31. or until local rainfall of 0.5 inches or 
greater falls within the subject watershed within a 24-hour 
period, whichever occurs first . 

* Creeks Not Supporting Anadromous Fish: 

An extended work window may occur from October 15 
through November 30 th . or until local rainfall of 0.5 inches or 
greater falls within the subject watershed within a 24-hour 
period, whichever occurs first. 

* In lower quality areas. w Work may occur after a significant 
rainfall event but no later than stops at first significant rainfal 
(0.5 inch e s of rain in a 24 - hr p e riod] or December 31r-per 


Vegetation Management 


General Description of 
Activities 


• In-Channel 

• Upland 


Additional conditions needed for work on Berryessa 
Creek (0-88+80; 232+70-236+00; 284+30-288+00], 
Lower Silver Creek (Reach 3 between Stations 37+40 and 
381+19], Thompson Creek (0+00-10+00], Canoas Creek 
(0+00-390+00], Ross Creek (0+00-86+30], Calabazas 
Creek (35+00-105+00], and San Tomas Aquino Creek 
(80+00-100+00], after a rainfall event (0.5 inch/24 
hours] 

Sites maintained in a winterized state during extended 
work window 


• Woody 

• Herbaceous 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-45 


December 2011 
Project 10.005 







2. Project Description 


Table 2-11. Comparison of Key Differences between 2002 SMP and 2012 SMP Update 


Description of Activity 2002 SMP 2012 SMP Update 

Pruning Activities 

Identified as a means to remove over-hanging 
growth in upland areas. 

Removal of instream vegetation by hand can occur 
between July 1-March 1 

• Now defined as a work activity which includes corrective 
pruning and coppicing, (for both in-channel and upland areas] 

• Outside the bankfull area, activity may occur year round, 
weather permitting. 

• Activity permitted year-round within the instream area 
except: 

- Where equipment would need to access a site by 
crossing a creek or would affect water quality 

- In steelhead streams - where work would be allowed 
until Dec. 31 or first significant rainfall occurs (greater 
than 0.5 inch/24 hours]/watershed, whichever 
transpires first. 

Hand Removal Activities 

Described as a means to remove vegetation both 
in-channel (trees, shrubs, and weeds] and upland 
areas, less than 6 inches dbh only, everywhere. 
Removal of instream vegetation by hand can occur 
between July 1-March 1 

Greater description of activity includes: 

• Hand-removal of woody vegetation occurs for the following 
reasons: 

- Maintenance (retain conveyance capacity] 

- Bank Stabilization 

- Ecological Health/Stewardship (includes habitat 
improvement, snag removal] 

• Stump treatment is included as hand removal (not considered 
Herbicide work], 

• Tree/shrub removal 6-12 inches dbh. Tree removal is subject 
to removal assessment process and criteria. 

• Timing same as described for Pruning Activities 

• "Pay as you go" mitigation 

• Additional requirements include supervision by qualified 
specialist for certain pruning types, and tree removal 
compliance with local tree ordinances. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-46 


December 2011 
Project 10.005 




2. Project Description 


Table 2-11. Comparison of Key Differences between 2002 SMP and 2012 SMP Update 


Description of Activity 2002 SMP 2012 SMP Update 

Mechanical Removal 

For control of herbaceous vegetation. Includes 
mowing and discing in upland areas. 

• Mowing work window=May-October 

• Discing work window= undefined 

Similar, though now includes instream mowing. 

• Mowing work window= February 1-November 30 

• Discing work window= February 1-October 15 

• Instream mowing work window= June 15-October 15 

Flaming 

Not included or described in the SMP. 

• Countywide, year-round 

• Limitations include application by trained staff, no use during 
periods of high fire danger, and notification to local fire 
districts upon request prior to use. 

Grazing 

Not included or described in the SMP 

• Where other herbaceous work activity is projected. 

• Year-round 

Herbicide Use 

• Limitations in Pajaro River Basin 

- Allowed only within channel for invasive 
vegetation removal. 

• BMPs call for avoidance of serpentine habitats. 

• Work windows 

- In aquatic areas July 1-October 15 

- Guadalupe River work window July 1- 
August 15 

- No application if rain is forecast within 72 
hours 

- Upland Areas year round except when rain 
is forecast within 72 hours 

• Additional guidance 

- Refer to product label and Endangered 
Species database for pesticide regulation 
for use within 1.25 miles of known CRLF 

areas 

Expanded activity location and timing: 

• Similar application in Santa Clara and Pajaro River Basins 

• Instream application window June 15-October 15 with 
extended window until Dec 31 or first significant rainfall 
(greater than 0.5 inch/24 hoursj/watershed, whichever 
transpires first. 

• Upland application window year-round, weather permitting 

• Limitations include 

- biological clearance required 

- pest control recommendation 

- Foliar application only to less than 2 inches dbh and less 
than 8-foot tall woody vegetation 

- Application allowed in serpentine areas with additional 
limitations 

- Use of aquatic herbicides in CRLF and CTS mapped areas 
only if creek is dry and no rain forecast for 48 hrs. 

• Includes use of surfactants on the 14 steelhead streams with 
additional limitations/considerations 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-47 


December 2011 
Project 10.005 




2. Project Description 


Table 2-12. BMPs Listings 

SECTION A -Pre-Project Planning and General BMPs 

General BMPs are applicable program-wide, for most routine SMP maintenance activities. These measures include standard construction 
practices and impact avoidance measures that will minimize potential environmental impacts. These BMPs will be implemented by the stream 
maintenance crew, as appropriate and as overseen by site managers, for all activities associated with the maintenance program. The majority of 
these BMPs are implemented prior to and during maintenance operations, though the level of activity varies depending on the work type. 


Other General BMPs are conducted prior to implementing maintenance activities on site. This group of measures includes procedures to identify 
site or maintenance constraints, such as biological or cultural resource surveys which coincide with permit compliance requirements. Site design 
constraints for sediment and bank stabilization activities in particular are also identified as part of the pre-project planning process. 


BMP Number 

BMP Title 

BMP Description 

GEN-1 

In-Channel Work Window 

All ground-disturbing maintenance activities (i.e., sediment removal, bank stabilization, tree removal, and 
mechanized vegetation management) occurring in the channel (below bankfull) will take place between June 15 
and October 15. Reauests for work window extensions must be submitted to the requlatorv aaencies bv October 

1 st , listinq the creek names and reaches where a work extension will occur. Work extensions vary per work activity. 

The aqencies will provide a sinqle response within one week. Siqnificant rainfall applies after October 15. An 

extension through December 31 may apply if the following requirements are met and regulatory agency approval is 
received: 

For ground-disturbing activities: 

■ Work may continue if no significant rainfall, defined as greater than 0.5 inches per 24 hours within a local 
watershed, is either forecasted 1 or observed. Following October 15 th , maintenance work shall cease for 
the season if such a rain event is forecasted or observed. 

Sediment removal 

■ Extended Work Window: 

1. Creeks Supportinq Anadromous Fish: 

An extended work window mav occur from October 15 throuqh October 31, or until local rainfall of 0.5 

inches or qreater falls within the subject watershed within a 24-hour period, whichever occurs first. 

2. Creeks Not SuoDortinq Anadromous Fish: 

An extended work window mav occur from October 15 throuqh November 30 th , or until local rainfall of 

0.5 inches or qreater falls within the subiect watershed within a 24-hour period, whichever occurs first. 

■ Extended Work Window in Lower Quality Areas: 

1. After a significant rainfall event (0.5 in/24 hrs), sSediment removal work mav occur until December 31. 


1 Weather Forecasts. No phase of the project may be started if that phase and its associated erosion control measures cannot be completed prior to the onset of a 
storm event if that construction phase may cause the introduction of sediments into the stream. Seventy-two-hour weather forecasts from the National Weather 
Service or other localized and more detailed weather forecast service will be consulted prior to start up of any phase of the project that may result in sediment 
runoff to a stream. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-48 


December 2011 
Project 10.005 





















2. Project Description 


BMP Number 

BMP Title 

BMP Description 



2. Work will onlv occur on Berrvessa Creek (0-88+80; 232+70-236+00; 284+30-288+00), Lower Silver 
Creek (Reach 3 between Stations 37+40 and 381+19), Thomason Creek (0+00-10+00), Canoas 

Creek (0+00-390+00), and-Ross Creek (0+00-86+30), Calabazas Creek (35+00-105+00), and San 
Tomas Aquino Creek (80+00-100+00) can continue with the followinq conditions: 

o site conditions are dry and access for all construction equipment and vehicles will not impact 
waterways; and 

o all work will stop if any rainfall is forecast for the next 72 hour period.r-artd 
e—email notification of work status will be provided to regulatory agencies two days in advance of 

scheduled work. 

3. Work mav occur after a sianificant rainfall event but no later than December 31. 

4. Sites must be maintained in a rapidly winterizable 1 state (implement control measures BMP GEN-20). 
Bank stabilization oroiects that are 50% complete bv October 15 mav continue until the approved date stated 
belowcompletion or until 0.5 inches of rain is predicted in the next 24-hr period. Prior to a forecasted siqnificant 
rainfall event (0.5 in/24 hrs), all incomplete bank stabilization projects must be winterized. 

1. In Creeks Supportinq Anadromous Fish 

o An extended work window mav occur until October 31 st for bank stabilization projects that will be 

50% complete bv October 15 tn . 

2. In Creeks Not Supportina Anadromous Fish 

o An extended work window mav occur until November 30 th for oroiects that will be 50% complete 

bv October 15 th or until sianificant rainfall. 

o An extended work window mav occur until November 30th for new bank stabilization projects that 

will be completed in five (5) days or less, or until siqnificant rainfall. 

■ Instream hand pruning and hand removal of vegetation will occur year round, except when: 

o Wheeled or tracked equipment needs to access the site by crossing a creek, ponded area, or 
secondary channel; or 

o Work occurs in streams that support steelhead. In these streams instream vegetation 
maintenance will cease on December 31 or when local rainfall greater than 0.5 inches is 
predicted within a 24-hour period of planned activities, whichever happens first. 

Modification and removal of instream larqe woodv debris will occur at anv time of the year, and as further described 
in the NMFS Bioloqical Opinion, if imminent danger of a flood threat precludes leaving the wood in place. 

GEN-2 

Instream Herbicide 
Application Work Window 

Instream herbicide applications will take place between June 15 and October 1534, with an extension through 
December 31 or until the first occurrence of any of the following conditions; whichever happens first: 

■ local rainfall greater than 0.5 inches is forecasted within a 24-hour period from planned application events; 
or 

■ when steelhead begin upmigrating and spawning in the 14 steelhead creeks, as determined by a qualified 


1 Winterization is the process to maintain work sites with the appropriate BMP’s to prevent erosion, sediment transport, and protect water quality. Winterization 
occurs upon completion of bank repairs or on incomplete projects after October 15 and prior to the forecast of significant rainfall, 0.5 inches or greater of local 
watershed rainfall within 24 hours. Winterization shall be completed prior to the occurrence of such actual significant rainfall. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-49 


December 2011 
Project 10.005 




































2. Project Description 


BMP Number 

BMP Title 

BMP Description 



biologist (typically in November/December), 

o A qualified biologist will determine presence/absence of sensitive resources in designated 
herbicide use areas and develop site-specific control methods (including the use of approved 
herbicide and surfactants). Proposed herbicide use would be limited to the aquatic formulation of 
qlvphosate (Rodeo or equal). Surfactant use would be limited to non-ionic products, such as Aqri- 
dex, Competitor, or another brand name using the same ingredients. Any modifications to these 
materials would require review and approval bv NMFS and CDFG. 
o A qualified fisheries biologist will review proposed herbicide application methods and stream 
reaches. The fisheries biologist would conduct a pre-construction survey (and any other 
appropriate data research) to determine whether the proposed herbicide application is consistent 
with SMP approvals concerning biological resources and determine which BMPs would be 
instituted for work to proceed. 

In addition, herbicide application requirements are as follows: 

■ no direct application into water; 

■ herbicide application shall not occur when wind conditions mav result in drift; 

■ herbicide shall only be applied after the surfactant has a “wet” appearance on the tarqet plants in order to 

avoid run off; and 

■ where permitted, surfactants shall be added to the SDrav solution Drior to aDDlication. 

GEN-3 

Avoid Exposing Soils with 
High Mercury Levels 

Sediment removal and bank stabilization projects in portions of the Guadalupe River watershed affected by historic 

mercury mining may expose soils containing mercury. 

1. In specified maintenance reaches in the Guadalupe River Basin, soils that are likely to be disturbed or excavated 

shall be tested for mercury (Hg). Soils shall be remediated if: 

a. disturbed or excavated soils exposed to streamflow below the elevation of the 2.33-year flow event exceed 

1 ppm Hg; or 

b. disturbed or excavated soils above the 2.33-year flow level exceed 20 ppm Hg. 

2. Remediation may be accomplished either by: 

a. treating the site so that contaminated soils excavated for the purpose of bank stabilization shall not be 
susceptible to erosion; or 

b. further excavating contaminated soils and replacing them with clean fill or other bank stabilization 
materials that are free from contaminants. 

c. Soils with mercury concentrations exceeding 20 mg/kg shall be removed and disposed of in a Class 1 
landfill following established work practices and hazard control measures. Soils with mercury 
concentrations less than 20 mg/kg will remain at the project site. 

3. To ensure worker safety during sediment removal and bank stabilization projects with elevated mercury 

concentrations in the exposed surfaces, personal protective equipment will be required during project 

construction to maintain exposure below levels established by the Occupational Safety and Health Agency 

(OSHA). 


Biological Resources 


GEN-4 


Minimize the Area of 


To minimize impacts to natural resources, soil disturbance will be kept to the minimum footprint necessary to 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-50 


December 2011 
Project 10.005 




















2. Project Description 


BMP Number 

BMP Title 

BMP Description 


Disturbance 

complete the maintenance operation. 

GEN-5 

Mitten Crab Control 

Measure 

Sediment from the San Francisco Bay Watershed, including that for reuse, cannot be moved to areas any farther 
south than Coyote Creek Golf Drive in south San Jose, and the intersection of McKean and Casa Loma Roads. 

GEN-6 

Minimize Impacts to 

Nesting Birds via Site 
Assessments and 

Avoidance Measures 

1. For activities occurring between January 15 and August 31, project areas will be checked by a qualified 
biologist or Designated Individuals (Dl - for limited ground nesting species surveys) T for nesting birds within 2 
weeks prior to starting work. If a lapse in project-related work of 2 weeks or longer occurs, another focused 
survey will be conducted before project work can be reinitiated. 

2. If nesting birds are found, a buffer will be established around the nest and maintained until the young have 
fledged. Appropriate buffer widths are 0.5 mile for bald and golden eagles; 250 feet for other raptors and the 
least Bell’s vireo, herons, and egrets; 25 feet for ground-nesting non-raptors; and 50 feet for non-raptors 
nesting on trees, shrubs and structures. A qualified biologist may identify an alternative buffer based on a site 
specific-evaluation. No work within the buffer will occur without written approval from a qualified biologist, for 
as long as the nest is active. 

3. All vegetation management, sediment reuse, road grading, or other SMP activities in or immediately adjacent 
to suitable California clapper rail or Alameda song sparrow nesting habitat, as determined by a qualified 
biologist, shall not be conducted prior to September 1 (the non-nesting season). 

4. If a pre-activity survey in high-quality San Francisco common yellowthroat breeding habitat (as determined by 
a qualified biologist) identifies more singing male San Francisco common yellowthroats than active nests, then 
the inconspicuous nests of this species might have been missed. In that case, maintenance activities in that 
area shall be delayed until the San Francisco common yellowthroat non-breeding season (i.e., August 16- 
March 14). 

5. The boundary of each buffer zone will be marked with fencing, flagging, or other easily identifiable marking if 
work will occur immediately outside the buffer zone. 

6. All protective buffer zones will be maintained until the nest becomes inactive, as determined by a qualified 
biologist. 

7. If monitoring shows that disturbance to actively nesting birds is occurring, buffer widths will be increased until 
monitoring shows that disturbance is no longer occurring. If this is not possible, work will cease in the area 
until young have fledged and the nest is no longer active. 

GEN-6.5 

Protection of Nestinq Least 

Bell’s Vireos 

1. To the extent feasible, SMP activities within woodv riparian habitat alonq portions of lower Llaqas Creek 

downstream from Hiqhwav 152, the Paiaro River from Llaqas Creek downstream, and lower Uvas/Carnadeo 

Creek downstream from Hecker Pass Road shall be scheduled to occur outside of the least Bell’s vireo nestinq 

season (March 15 - July 31). 

2. For activities within woodv riparian habitat alonq the aforementioned creek reaches that will occur between 

March 15 and July 31, anv work will be preceded bv a focused survey for least Bell’s vireos. Pre-activitv 

surveys will consist of two site visits, conducted on separate days within 14 days before the initiation of 

maintenance activities in the qiven area, with at least one of these surveys occurrinq within 7 days before the 

initiation of such activities. Surveys will be conducted between dawn and 11:00 a.m., durinq mild weather 

conditions (i.e., not durinq excessive cold, heat, wind, or rain}, within all riparian habitat in and within 250 feet 

of anv proposed maintenance location alonq these reaches. The surveys will be conducted bv a qualified 

bioloqist who is familiar with the visual and auditory identification of this species. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-51 


December 2011 
Project 10.005 

























2. Project Description 


BMP Number 

BMP Title 

BMP Description 



3. To minimize impacts to nestina least Bell’s vireos and other birds, the bioloaist will not initially be lookina for 

Bell’s vireo nests durina these surveys. Rather, the bioloaist will look and listen for individual vireos. If a least 

Bell’s vireo is detected, it will be observed to determine whether it is actively nestina. The bioloaist will note the 

nest location, or if findina the actual nest could result in excessive disturbance or risk damaaina the nest, the 

bioloaist will determine the approximate location, based on observation of birds carrvina nestina material, 

carrvina food, or repeatedly visitina a certain area. 

4. If an active nest is found, a minimum 250-foot no-activitv buffer will be established around the nest. If a 

territorial male is found but no nest can be detected, then the aooroximate centroid of the bird’s area of activitv 

will be the point from which the buffer will be applied. The reauired buffer mav be reduced in areas where 

dense riparian forest occurs between the construction activities and the active nest or where sufficient barriers 

or topoaraphic relief exists to protect the nest from excessive noise or other disturbance. The bioloaist will 

coordinate with the USFWS and CDFG to evaluate exceptions to the minimum no-activitv buffer distance on a 

case-bv-case basis. 

5. No work will occur within the buffer without verification bv a bioloaist that the nest is inactive and until anv 

fledaed vouna are no lonaer dependent on adults for food. 

GEN-7 

Protection of Burrowing 

Owls 

1. If burrowina owls are present, then wWork within 250 feet of an occupied burrow will be delayed until after the 
nesting season. 

2. If suitable burrowing owl habitat is identified where mowing is proposed, or active burrows are found, they will 
be marked in such a way that the mower can identify the locations of such burrows. Mowing can then occur 
anywhere beyond the 250 foot buffer zone. Within the 250 foot buffer zone mowing may be done to within 10 
feet of an active burrow provided there areis no burrowing owls active on the surface. An on-site monitor will 
observe the area in front of the mower from a safe vantage point while it is in operation. In areas within 10 ft of 
active burrows the vegetation may be removed by hand (e.g., weed-whackers). All mowing and hand-removal 
of vegetation within 250 ft of a burrow will be done as quickly as possible to minimize disturbance of burrowing 
owls. 

3. All markers will be removed once mowing is complete. 

4. For burrow destruction work, all burrows within the 250-foot buffer zone around known, occupied burrows will 
be inspected with a burrow camera prior to destruction to ensure no entrapment of burrowing owls. Burrows 
that are difficult to inspect due to intricate subterranean configuration or depth will be inspected in stages 
where the uninspected section of the burrow will be protected while the previously inspected section is 
excavated. 

If maintenance activities will directly impact occupied burrows the District will consult with the DFG and FWS on 
establishing alternative burrows (including artificial burrows) and a process for removing owls from the active 
burrow. No burrowing owls will be evicted from burrows during the nesting season. 

GEN-8 

Protection of Sensitive 
Fauna Species from 
Herbicide Use 

Approved herbicides and adjuvants may be applied in habitat areas for sensitive wildlife species (including 
steelhead, California red-legged frog, California tiger salamander, salt marsh harvest mouse, and Bay checkerspot 
butterfly); all applications will occur in accordance with federal and state regulations. 

For sprayable or dust formulations: when the air is calm or moving away from sensitive wildlife habitat, applications 
will commence on the side nearest the habitat and proceed away from the habitat. When air currents are moving 
toward habitat, applications will not be made within 200 yards by air or 40 yards by ground upwind from occupied 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-52 


December 2011 
Project 10.005 


























2. Project Description 


BMP Number 

BMP Title 

BMP Description 



habitat. However, these distances may be modified for the control of invasive species on salmonid streams if the 
following measures are implemented: 

■ A qualified biologist will determine presence/absence of sensitive resources in designated herbicide use 
areas and develop site-specific control methods (including the use of approved herbicide and surfactants). 
Proposed herbicide use would be limited to the aquatic formulation of glyphosate (Rodeo or equal). 
Surfactant use would be limited to non-ionic products, such as Aqri-dex, Competitor, or another brand 
name using the same ingredients. Any modifications to these materials would require review and approval 
bv NMFS and CDFG. 

■ A qualified fisheries biologist will review proposed herbicide application methods and stream reaches. The 
fisheries biologist would conduct a pre-construction survey (and any other appropriate data research) to 
determine whether the proposed herbicide application is consistent with SMP approvals concerning 
biological resources and determine which BMPs would be instituted for work to proceed. 

GEN-9 

Avoid Impacts to Special- 
Status Plant Species and 
Sensitive Natural 

Vegetation Communities 

A qualified botanist will identify special status plant species and sensitive natural vegetation communities and 

clearly map or delineate them as needed in order to avoid and/or minimize disturbance, usinq the DFG protocols 

and the CNPS Botanical Survey Guidelines to formulate the followinq protocols: 

1. A qualified botanist will use the GIS database, CNDDB, and/or other suitable tools to identify special status 
plants and sensitive natural vegetation communities located within or near work areas. 

2. Surveys of areas identified as sensitive natural communities or suitable habitat for special status plant species 
will be conducted by a qualified botanist prior to commencement of work. 

3. Surveys will be conducted durinq the appropriate time of the year to adequately identify special-status plants 
that could occur on the site of proposed maintenance activities. 

4. The qualified botanist will ensure avoidance and/or minimize impacts by implementing one or more of the 
following, as appropriate, per the botanist’s recommendation: 

a) Flag or otherwise delineate in the field the special status plant populations and/or sensitive natural 
community to be protected; 

b) Allow adequate buffers around plants or habitat; the location of the buffer zone will be shown on the 
maintenance design drawings and marked in the field with stakes and/or flagging in such a way that 
exclusion zones are visible to maintenance personnel without excessive disturbance of the sensitive 
habitat or population itself (e.g., from installation of fencing). 

c) Time construction or other activities during dormant and/or non-critical life cycle period; 

d) Store removed sediment off site; and 

e) Limit the operation of maintenance equipment to established roads whenever possible. 

5. No herbicides, terrestrial or aquatic, will be used in areas identified as potential habitat for special status 
plants species or containing sensitive natural communities, until a qualified botanist has surveyed the area 
and determined the locations of special status plant species present. 

6. If special status plant species or sensitive communities are present, then a qualified botanist will determine if a 
given type of vegetation management method is ecologically appropriate for a given area. Alternative 
strategies based on the botanist’s recommendations will be coordinated with appropriate staff. 

7. All impacts to sensitive natural communities and special status plants identified by the qualified botanist will be 
avoided and/or minimized 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-53 


December 2011 
Project 10.005 














2. Project Description 


BMP Number 

BMP Title 

BMP Description 

GEN-10 

Avoid Impacts to Bay 
Checkerspot Butterfly and 
Associated Critical Habitat 

1. Areas supporting Bay checkerspot larval host plants will be identified by a qualified botanist and protected 
from disturbance to the extent feasible, bv establishinq buffer zones around individual plants or copulations. 
The size of the buffer will be determined by a qualified botanist; the actual distance will depend on the plant 
species potentially affected and the type of disturbance. No herbicide will be applied to the buffer area, and 
to the extent feasible, maintenance personnel and equipment will not operate within such areas. 

2. Herbicides may be used in serpentine areas that do not contain Bay checkerspot butterfly larval host plants 
or sensitive plant species and habitat when approved by a qualified botanist and for the following 
maintenance purposes: 

a) To protect sensitive species and habitat; 

b) To manage for control of invasive and non-native plants; and/or 

c) To maintain access to a facility. 

GEN-11 

Protection of Salt Marsh 
Harvest Mouse and 
California Clapper Rail 

1. A District qualified biologist will conduct a desk audit to determine whether suitable Salt Marsh Harvest Mouse 
(SMHM) or California Clapper Rail (CCR) habitat is present in or adjacent to a maintenance activity. 

2. Within 7 days prior to work within the range of the Salt Marsh Harvest Mouse (SMHM) or California Clapper 

Rail (CCR), as depicted on the District’s GIS layers, the proposed project area will be surveyed by a qualified 
biologist to identify specific habitat areas. Surveyed areas will include work locations and access routes. 

3. To minimize or avoid the loss of individuals, activities within or adjacent to California clapper rail and salt marsh 
harvest mouse habitat will not occur within two hours before or after extreme high tides (6.5 feet or above) 
when the marsh plain is inundated, because protective cover for those species is limited and activities could 
prevent them from reaching available cover. 

4. Specific habitat areas are veaetated areas of cordaass (Soartina sod), marsh aumolant (Grindelia sood, 
pickleweed ( Sarcocornia pacifica ), alkali heath, ( Frankenia sp.), and other high marsh vegetation, brackish 
marsh reaches of creek with heavy accumulations of bulrush thatch (old stands), and high water refugia habitat 
that may include annual grasses, and shrubs immediately adjacent to channels. 

5. Within the identified specific habitat areas, vegetation will be removed by hand from areas to be directly 
impacted by the work activities if possible (hand removal of vegetation in some channels may not be possible). 

6. Prior to the initiation of work each day for all vegetation management work, ground or vegetation disturbance, 
operation of large equipment, grading, sediment removal, and bank stabilization work and prior to expanding 
the work area, if suitable habitat occurs within the immediate work area, a qualified biologist will conduct a pre¬ 
construction survey of all suitable habitat that may be directly or indirectly impacted by the day’s activities 
(work area, access routes, staging areas). 

a. If during the initial daily survey or during work activities a CCR is observed within or immediately 
adjacent to the work area (50 feet), initiation of work will be delayed until the CCR leaves the work area. 

b. If during the initial daily survey or during work activities a SMHM or similar rodent is observed within or 
immediately adjacent to the work area (50 feet), initiation of work will be delayed until a Site Specific 
Species Protection Form can be developed and implemented by a qualified biologist to protect the 

SMHM or similar rodent is developed and implemented by the qualified biologist. Acceptable plan 
activities may include one or more of the following activities: 1) establishment of a buffer zone at least 50 
feet in radius from the rodent; 2) ongoing active monitoring, 3) construction of silt fence barrier between 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-54 


December 2011 
Project 10.005 











2. Project Description 


BMP Number 

BMP Title 

BMP Description 



maintenance work and location of the rodent, 4) delay of work activity until the qualified biologist can 
contact DFG and USFWS for additional direction. 

7. Mowing using heavy equipment (tractors, boom mowers, rider mowers) will not be conducted in habitat areas 
or within 50 feet of habitat areas. If mowing with hand equipment is necessary within 50 feet of habitat areas, 
an on-site monitor will observe the area in front of the mower from a safe vantage point while it is in operation. 

If SMHM are detected within the area to be mown, no mowing will occur in that area. If CCR are detected 
within the area to be mown, the mowing will stop until the individual(s) have left the work area. 

8. See ANI-2 for additional restrictions. 

GEN-12 

Protection of Special-Status 
Amphibian and Reptile 
Species 

1. A District qualified biologist will conduct a desk audit to determine whether suitable special-status amphibian or 
reptile habitat is present in or adjacent to a maintenance activity. 

2. If the District Wildlife or Fisheries Biologist determines that a special-status amphibian or reptile could occur in 
the activity area, a qualified biologist will conduct one daytime survey within a 7 day period preceding the onset 
of maintenance activities. 

a. If a special-status amphibian or reptile, or the eggs or larvae of a special status amphibian or reptile, 
isare found within the activity area during a pre-activity survey or during project activities, the qualified 
biologist shall notify the project proponent about the special-status species and conduct the following 
work specific activities: 

i. For minor maintenance activities and for vegetation removal activities that will take less than 1 day, 
the qualified biologist shall conduct a special status species survey on the morning of and prior to the 
scheduled work. 

A. If no special status species is found, the work may proceed. 

B. If eggs or larvae of a special status species are found, a buffer will be established around the 
location of the eggs/larvae and work may proceed outside of the buffer zone. No work will 
occur within the buffer zone. Work within the buffer zone will be rescheduled until the time that 
eggs have hatched and/or larvae have metamorphosed. 

C. If an active western pond turtle nest is detected within the activity area, a 25-50-foot buffer 
zone around the nest will be established and maintained during the breeding and nesting 
season (April 1 - August 31). The buffer zone will remain in place until the young have left the 
nest, as determined by a qualified biologist. 

D. If adults or non-larval juveniles of a special status species are found, one of the following two 
procedures will be implemented: 

i. If, in the opinion of the qualified biologist, capture and removal of the individual to a safe 
place outside of the work area is less likely to result in adverse effects than leaving the 
individual in place and rescheduling the work (e.g., if the species could potentially hide 
and be missed during a follow-up survey), the individual will be captured and relocated 
by a qualified biologist (with USFWS and/or CDFG approval, depending on the listing 
status of the species in question), and work may proceed. 

ii. If, in the opinion of the qualified biologist, the individual is likely to leave the work area 
on its own, and work can be feasibly rescheduled, a buffer will be established around 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-55 


December 2011 
Project 10.005 








2. Project Description 


BMP Number 

BMP Title 

BMP Description 



the location of the individual(s) and work may proceed outside of the buffer zone. No 
work will occur within the buffer zone. Work within the buffer zone will be rescheduled. 

ii. For minor maintenance and vegetation removal activities that will take more than 1 day, the qualified 
biologist shall conduct a special-status species survey on each morning of and prior to the scheduled 
work commencing. 

E. If eggs or larvae of a special status species are found, a buffer will be established around the 
location of the eggs/larvae and work may proceed outside of the buffer zone. No work will 
occur within the buffer zone. Work within the buffer zone will be rescheduled until the time that 
eggs have hatched and/or larvae have metamorphosed. 

F. If an active western pond turtle nest is detected within the activity area, a 2550 ft-buffer zone 
around the nest will be established and maintained during the breeding and nesting season 
(April 1 - August 31). The buffer zone will remain in place until the young have left the nest, as 
determined by a qualified biologist. 

G. If adults or non-larval juveniles of a special status species are found, the individual will be 
captured and relocated by a qualified biologist (with USFWS and/or CDFG approval, 
depending on the listing status of the species in question), and work may proceed. 

iii. For Sediment Removal and Bank Stabilization Projects the wildlife or fisheries biologist in cooperation 
with the project proponent shall complete a Site Specific Species Protection Form for the project. 
Elements of the form include: work rescheduling, training work crews, daily surveys, establishment of 
buffers and buffer fencing, on-site monitoring, habitat modification in advance of work activities, capture 
and relocation of individual special-status species, methods of documentation, and reporting of results. 

b. If no special status amphibian or reptile is found within the activity area during a pre-activity survey, the 
work may proceed. 

c. During animal conflict management activities, if special status species are found within a burrow proposed 
for destruction, a qualified biologist will determine an appropriate buffer distance around that burrow to 
ensure adequate protection of the habitat. The buffer area may include not destroying adjacent burrows as 
that may damage subterranean networks of the occupied burrow or produce substrate vibrations which 
could interfere with prey detection mechanisms. If two consecutive follow up surveys are conducted (spaced 
30 days apart) in which the burrow is found to be unoccupied, work can proceed as planned. A naturally 
found back filled burrow known to have been inhabited by a special-status species will be presumed to still 
be occupied by that species and a clearly delineated buffer demarcation of the burrow area will be in place 
for the duration of nearby work activities. In rare instances in which destruction of the burrow is not 
avoidable during animal conflict management, the animal will be relocated to a safe burrow outside the 
impact area, with USFWS and/or CDFG approval, depending on the listing status of the species in question. 
A biologist will observe the relocated animal until it is certain that the animal is not in immediate danger of 
desiccation or predation. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-56 


December 2011 
Project 10.005 







2. Project Description 


BMP Number 

BMP Title 

BMP Description 

GEN-13 

Protection of Bat Colonies 

1. A District Wildlife Biologist will conduct a desk audit to determine whether suitable habitat (appropriate roost 
trees or anthropogenic structures) is present for bat colonies within 100 feet of the work site, staging areas, or 
access routes. 

2. If potential bat colony habitat is determined to be present, within two weeks prior to the onset of work activities 
a qualified biologist will conduct a survey to look for evidence of a bat use. If evidence is observed, or if 
potential roost sites are present in areas where evidence of bat use might not be detectable (such as a tree 
cavity), an evening survey and/or nocturnal acoustic survey may be necessary to determine if the bat colony is 
active and to identify the specific location of the bat colony. 

3. If an active bat maternity colony is present then the qualified biologist will make the following determinations: 

a. The work can proceed without unduly disturbing the bat colony 

b. There is a need for a buffer zone to prevent disturbance to the bat colony, and implementation of 
the buffer zone (determined on a case-bv-case basis bv a aualified bioloqist) will reduce or 
eliminate the disturbance to an acceptable level. 

c. Work cannot proceed without unduly disturbing the bat colony; thus, the work will be postponed 
until after July 31. 

4. If a non-breeding bat hibernaculum is found in a tree or structure that must be removed or physically disturbed, 
the qualified biologist will consult with DFG prior to initiating any removal or exclusion activities. 

GEN-14 

Protection of San Francisco 
Dusky-footed Wood rat 

1. Prior to work within riparian, oak woodland, or coyote brush scrub habitat, or the removal of any oak trees 
outside these habitats, a District Wildlife Biologist will conduct a desk audit to determine whether woodrats 
could be present within suitable habitat for San Francisco dusky-footed woodrat or is known to be present in or 
adjacent to a maintenance activity site. 

2. If the District Wildlife Biologist determines that no San Francisco dusky-footed woodrat habitat is present, or 
there is habitat present but will not be affected by the maintenance activity, then no further action is required. 

3. If the District Wildlife Biologist determines that suitable San Francisco dusky-footed woodrat habitat is present 
and may be affected by the maintenance activity, a qualified biologist shall conduct a pre-activity survey within 

2 weeks prior to the start of work to determine if woodrat nests are in, or within 5 feet of, the immediate activity 
area. 

a. If woodrat nests are present at the site and will be affected by the work activity area, the District Wildlife 
Biologist in cooperation with the project proponent will evaluate the site specific situation. The Wildlife 
Biologist will then develop a site specific woodrat management plan to first avoid and second minimize 
take or injury of the woodrat(s). The woodrat management plan may include: establishment of buffers 
zones, installation of buffer zone fences, relocation of the woodrat nest, removal of the woodrat nest, 
and/or construction of artificial nests. Consideration will be given to the number of woodrat nests that may 
be affected by the work activity and the number in the project vicinity that may not be affected. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-57 


December 2011 
Project 10.005 









2. Project Description 


BMP Number 

BMP Title 

BMP Description 

GEN-15 

Salvage Native Aquatic 
Vertebrates from Dewatered 
Channels 

If fisheries or native aquatic vertebrates are present when cofferdams, water bypass structures, and silt barriers are 
to be installed, a fish and native aquatic vertebrate relocation plan shall be implemented to ensure that fish and 
native aquatic vertebrates are not stranded. Relocation efforts will be based on the District’s Fish Relocation 
Guidelines. Streams that support a sensitive species (i.e. steelhead) will require a relocation effort and/ or initial 
onsite monitoring by a qualified biologist depending on seasonal conditions: 

1. In non-tidal channels, where water is to be diverted, prior to the start of work or during the installation of water 
diversion structures, native aquatic vertebrates shall be captured in the work area and transferred to another 
reach as determined by a qualified biologist. Timing of work in streams that supports a significant number of 
amphibians will be delayed until metamorphosis occurs to minimize impacts to the resource. Capture and 
relocation of aquatic native vertebrates is not required at individual work sites when site conditions preclude 
reasonably effective operation of capture gear and equipment. 

2. Aquatic invertebrates will not be transferred (other than incidental catches) because of their anticipated 
abundance and colonization after completion of the repair work. 

GEN-15.5 

Avoidance of Impacts on 
the San Joaquin Kit Fox 

1. A qualified District biologist will conduct a desk audit to determine whether an SMP activity will occur in an area 
where the San Joaquin kit fox could potentially occur (i.e., roughly east of Frazier Lake Road and south of 
Bloomfield Avenue), and in potential habitat for the species. 

2. If the District biologist determines that an SMP activity could occur in an area that could potentially support a kit 
fox, the SCVWD will implement applicable pre-activity surveys and other measures in accordance with the 
USFWS’s San Joaquin Kit Fox Survey Protocol for the Northern Range, as follows: 

a) Conduct a preconstruction/pre-activity survey no less than 14 days and no more than 30 days prior to 
the beginning of project implementation. Surveys shall identify kit fox habitat features on the project site 
and evaluate use by kit fox and, if possible, and assess the potential impacts to the kit fox by the 
proposed activity. The status of all dens shall be determined and mapped in accordance with the survey 
protocol. 

b) If a natal/pupping den is discovered within the project area or within 200 feet of the project boundary, 
the USFWS shall be immediately notified. Disturbance to all San Joaquin kit fox dens should be avoided 
to the maximum extent possible. Destruction of any known or natal/pupping kit fox den would require 
take authorization from the USFWS. 

c) The project proponent will establish exclusion zones around the kit fox dens, if determined to be 
present. The configuration of the exclusion should have a radius measured outward from the entrance 
or cluster of entrances. The following radii are minima to be applied: 

• Potential den: 50 feet 

■ Known den: 100 feet 

■ Natal/pupping den: Service must be contacted (occupied and unoccupied) 

■ Atypical den: 50 feet. 

3. If take of the San Joaauin kit fox will occur, take authorization from the USFWS and CDFG will be necessary. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-58 


December 2011 
Project 10.005 









2. Project Description 


BMP Number |BMP Title|BMP Description 


General Maintenance Practices 


GEN-16 

In-Channel Minor Activities 

For in-channel minor work activities, work will be conducted from the top of the bank if access is available and there 
are flows in the channel. 

GEN-17 

Employee/Contractor 

Training 

All appropriate District staff and contractors will receive annual training on Stream Maintenance Program BMPs. 

The training will also include an overview of special-status species identification and habitat requirements. District 
staff and contractors will receive fact sheets to assist with in-the-field identification of special-status species and 
their habitats. 

GEN-18 

Paperwork Required On¬ 
site 

1. Copies of regulatory permits related to the Stream Maintenance Program will be kept on-site and available 
for review, if requested by regulatory personnel. 

2. Copies of the Stream Maintenance Program Manual and this BMP Manual will be kept on-site. 

GEN-19 

Work Site Housekeeping 

1. District employees and contractors will maintain the work site in neat and orderly conditions on a daily basis, 
and will leave the site in a neat, clean, and orderly condition when work is complete. 

2. Slash, sawdust, cuttings, etc. will be removed to clear the site of vegetation debris. As needed, paved access 
roads and trails will be swept and cleared of any residual vegetation or dirt resulting from the maintenance 
activity. 

3. For activities that last more than one day, materials or equipment left on the site overnight will be stored as 
inconspicuously as possible, and will be neatly arranged. Any materials and equipment left on the site 
overnight will be stored to avoid erosion, leaks, or other potential impacts to water quality (see BMPs GEN- 
24). 

4. The District’s maintenance crews are responsible for properly removing and disposing of all debris incurred 
as a result of construction within 72 hours of project completion. 

5. All trash that is brought to a project site during maintenance activities (e.g., plastic water bottles, plastic lunch 
bags, cigarettes) will be collected at the site daily. 

GEN-20 

Erosion and Sediment 
Control Measures 

1. Soils exposed due to maintenance activities will be seeded and stabilized using hydroseeding, straw 
placement, mulching, and/or erosion control fabric. These measures will be implemented such that the site is 
stabilized and water quality protected prior to significant rainfall. The channel bed and areas below the 
Ordinary High Water Mark (OHWM) are exempt from this BMP. 

2. The preference for erosion control fabrics will be to consist of natural fibers; however, steeper slopes and 
areas that are highly erodible may require more structured erosion control methods. No non-porous fabric will 
be used as part of a permanent erosion control approach. Plastic sheeting may be used to temporarily 
protect a slope from runoff, but only if there are no indications that special-status species would be impacted 
by the application. 

3. Erosion control measures will be installed according to manufacturer’s specifications. 

4. Appropriate measures include, but are not limited to, the following: 

o Silt Fences 

o Straw Bale Barriers 

o Brush or Rock Filters 

o Storm Drain Inlet Protection 

o Sediment Traps 

o Sediment Basins 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-59 


December 2011 
Project 10.005 












2. Project Description 


BMP Number 

BMP Title 

BMP Description 



o Erosion Control Blankets and Mats 

o Soil Stabilization (i.e. tackified straw with seed, jute or geotextile blankets, etc.) 
o Wood chips 
o Straw mulch 

5. All temporary construction-related erosion control methods shall be removed at the completion of the project 
(e.g. silt fences). 

6. Surface barrier applications installed as a method of animal conflict management, such as chain link fencing, 
woven geotextiles, and other similar materials, will be installed no longer than 300 feet, with at least an equal 
amount of open area prior to another linear installation; and only on one side of levee slopes. Inboard and 
outboard areas will only have installations set in an alternating pattern, such that no inboard and outboard 
levee faces would have erosion control blankets along the same levee stationing. 

GEN-21 

Staging and Stockpiling of 
Materials 

1. To protect on-site vegetation and water quality, staging areas should occur on access roads, surface streets, 
or other disturbed areas that are already compacted and only support ruderal vegetation. Similarly, all 
maintenance equipment and materials (e.g., road rock and project spoil) will be contained within the existing 
service roads, paved roads, or other pre-determined staging areas. 

2. Building materials and other maintenance-related materials, including chemicals and sediment, will not be 
stockpiled or stored where they could spill into water bodies or storm drains. Materials will not be stockpiled 
longer than seven (7) calendar days. 

3. No runoff from the staging areas may be allowed to enter water ways, including the creek channel or storm 
drains, without being subjected to adequate filtration (e.g., vegetated buffer, swale, hay wattles or bales, silt 
screens). 

4. The discharge of decant water to water ways from any on-site temporary sediment stockpile or storage areas 
is prohibited. 

5. Wet material removed from an isolated creek reach may be pulled to the side of the channel (within the 
channel and below top of bank) and allowed to naturally drain prior to removal from the channel. Pulled 
material will be removed from the channel prior to deactivation of the site or forecast of rain. 

6. During the wet season, no stockpiled soils will remain exposed, unless surrounded by properly installed and 
maintained (i.e., per manufacturer specifications) silt fencing or other means of erosion control. During the 
dry season; exposed, dry stockpiles will be watered, enclosed, covered, or sprayed with non-toxic soil 
stabilizers (GEN-24). 

7. All pipes, culverts, or similar structures stored at a site within sensitive species areas, for one or more 
overnight periods shall be securely capped prior to storage or inspected before the pipe is subsequently 
moved. If any potential special-status species are observed within a pipe, a District biologist shall be 
consulted on what steps should be taken to protect the species. If a District biologist is on-site, they may 
remove the special status species from the pipes and relocate to the nearest appropriate and unaffected 
habitat. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-60 


December 2011 
Project 10.005 








2. Project Description 


BMP Number 

BMP Title 

BMP Description 

GEN-22 

Sediment Transport 

To prevent sediment-laden water from being released back into waterways during transport of spoils to disposal 
locations, truck beds will be lined with an impervious material (e.g., plastic), or the tailgate blocked with wattles, hay 
bales, or other appropriate filtration material. Trucks may then drain excess water by slightly tilting the loads and 
allowing the water to drain out through the applied filter, but only within the active project area of the creek where 
the sediment is being loaded into the trucks or within an identified vegetated area (swale) that is separated from the 
creek. 

GEN-23 

Stream Access 

District personnel will use existing access ramps and roads to the extent feasible. If necessary to avoid large 

mature trees, native vegetation, or other significant habitat features, temporary access points will be constructed in 

a manner that minimizes impacts according to the following guidelines: 

1. Temporary access points will be constructed as close to the work area as possible to minimize equipment 
transport 

2. In considering channel access routes, slopes of greater than 20 percent will be avoided, if possible. 

3. Any temporary fill used for access will be removed upon completion of the project and pre-project topography 
will be restored to the extent possible. 

4. When temporary access is removed, disturbed areas will be revegetated or filled with compacted soil, seeded, 
and/or stabilized with erosion control fabric immediately after construction to prevent future erosion. 

5. Personnel will use the appropriate equipment for the job that minimizes impacts and disturbance to the stream 
bottom. Appropriately-tired vehicles, either tracked or wheeled, will be used depending on the site and 
maintenance activity. 

GEN-24 

On-Site Hazardous 

Materials Management 

1. An inventory of all hazardous materials used (and/or expected to be used) at the worksite and the end 
products that are produced (and/or expected to be produced) after their use will be maintained by the worksite 
manager. 

2. As appropriate, containers will be properly labeled with a “Hazardous Waste” label and hazardous waste will 
be properly recycled or disposed of off-site. 

3. Contact of chemicals with precipitation will be minimized by storing chemicals in watertight containers with 
appropriate secondary containment to prevent any spillage or leakage. 

4. Quantities of toxic materials, such as equipment fuels and lubricants, will be stored with secondary 
containment that is capable of containing 110% of the primary container(s). 

5. Petroleum products, chemicals, cement, fuels, lubricants, and non-storm drainage water or water 
contaminated with the aforementioned materials will not contact soil and not be allowed to enter surface 
waters or the storm drainage system. 

6. All toxic materials, including waste disposal containers, will be covered when they are not in use, and located 
as far away as possible from a direct connection to the storm drainage system or surface water. 

7. Sanitation facilities (e.g., portable toilets) will be placed outside of the creek channel and floodplain. Direct 
connections with soil, the storm drainage system, and surface waters will be avoided. 

8. Sanitation facilities will be regularly cleaned and/or replaced, and inspected daily for leaks and spills.^ 

GEN-25 

Existing Hazardous 

Materials 

If hazardous materials, such as oil, batteries or paint cans, are encountered at the maintenance sites, the District 
will carefully remove and dispose of them according to applicable regulatory requirements. District staff will wear 
proper protective gear and store the waste in appropriate hazardous waste containers until it can be disposed at a 
hazardous waste facility. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-61 


December 2011 
Project 10.005 










2. Project Description 


BMP Number 

BMP Title 

BMP Description 

GEN-26 

Spill Prevention and 
Response 

The District will prevent the accidental release of chemicals, fuels, lubricants, and non-storm drainage water into 
channels following these measures: 

1. District field personnel will be appropriately trained in spill prevention, hazardous material control, and 
clean up of accidental spills. 

2. Equipment and materials for cleanup of spills will be available on site and spills and leaks will be cleaned 
up immediately and disposed of according to applicable regulatory requirements. 

3. Field personnel will ensure that hazardous materials are properly handled and natural resources are 
protected by all reasonable means. 

4. Spill prevention kits will always be in close proximity when using hazardous materials (e.g., at crew trucks 
and other logical locations). All field personnel will be advised of these locations. 

5. District staff will routinely inspect the work site to verify that spill prevention and response measures are 
properly implemented and maintained. 

Spill Response Measures: 

For small spills on impervious surfaces, absorbent materials will be used to remove the spill, rather than hosing it 
down with water. For small spills on pervious surfaces such as soil, the spill will be excavated and properly 
disposed rather than burying it. Absorbent materials will be collected and disposed of properly and promptly. 

If a hazardous materials spill occurs that cannot be contained or cleaned up with the onsite materials, the onsite 
District field personnel will be responsible for immediately initiating an emergency response sequence by notifying 
the proper authorities (i.e., District Emergency Response (ER) Team and public fire and hazmat agencies) of the 
release; taking appropriate defensive steps from a safe distance to secure the site to minimize damage to people, 
environment, and property (PEP); and deferring all other response activities to public emergency response 
agencies and/or the District Emergency Response (ER) Team or District ER Contractor. Depending on the nature 
of the release, the District ER Team’s actions will include: urgent (responding within 2 hours of notification) field 
response site reconnaissance, emergency sequence initiation, defensive containment, release control, incident 
command; or priority (non 2-hour) field response site reconnaissance and clean-up operations. 

If a “reportable” spill of petroleum products occurs, the District’s Stream Maintenance Implementation Program 
Manager will be notified and action taken to contact the appropriate safety and cleanup crews. A reportable spill is 
defined as when: 

■ a film or sheen on, or discoloration of, the water surface or adjoining bank/shoreline is observed; or 

■ a sludge or emulsion is deposited beneath the surface of the water or adjoining banks/shorelines (40 

Code of Federal Regulations 110); or when 

■ another violation of water quality standards is observed. 

A written description of the reportable release must be submitted to the appropriate Regional Water Quality Control 
Board and the California Department of Toxic Substances Control (DTSC). This submittal must contain a 
description of the release, including the type of material and an estimate of the amount spilled, the date of the 
release, an explanation of why the spill occurred, and a description of the steps taken to prevent and control future 
releases. 

If an appreciable spill has occurred, and results determine that project activities have adversely affected surface 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-62 


December 2011 
Project 10.005 







2. Project Description 


BMP Number 

BMP Title 

BMP Description 



water or groundwater quality, a detailed analysis will be performed to the specifications of DTSC to identify the 
likely cause of contamination. This analysis will include recommendations for reducing or eliminating the source or 
mechanisms of contamination. Based on this analysis, the District or contractors will select and implement 
measures to control contamination, with a performance standard that surface and groundwater quality will be 
returned to baseline conditions. These measures will be subject to approval by the District, DTSC, and the Regional 
Water Quality Control Board. 

GEN-27 

Existing Hazardous Sites 

Upon selection of maintenance project locations, the District will conduct a search for existing known contaminated 
sites, as part of its annual preparation of the Notice of Proposed Work (NPW), on the State Water Resource Control 
Board’s GeoTracker Web site (http://www.geotracker.waterboards.ca.gov). The Geotracker search will only be 
performed for the District’s ground disturbing activities. For any proposed ground disturbing maintenance sites 
located within 1,500 feet of any “open” sites where contamination has not been remediated, the District will contact 
the RWQCB case manager listed in the database. The District will work with the case manager to ensure 
maintenance activities would not affect cleanup or monitoring activities or threaten the public or environment. 

GEN-28 

Fire Prevention 

1. All earthmoving and portable equipment with internal combustion engines will be equipped with spark 
arrestors. 

2. Durinq the hiqh fire danqer oeriod (Aoril 1-December 1 ), work crews will: at Hhave aoDrooriate fire 
suppression equipment available at the work site. 

GEN-29 

Dust Management 

The District will implement the Bay Area Air Quality Management District’s (BAAQMD) required Dust Control 
Measures 

(http://www.baaqmd.goV/~/media/Files/Planning%20and%20Research/CEQA/BAAQMD%20CEQA%20Guidelines 
%20May%202011 .ashx?la=en). Current measures stipulated by the BAAQMD Guidelines include the following: 

1. All exposed surfaces (e.g., parking areas, staging areas, soil piles, graded areas, and unpaved access roads) 
shall be watered two times per day. 

2. All haul trucks transporting soil, sand, or other loose material off-site shall be covered. 

3. All visible mud or dirt track-out onto adjacent public roads shall be removed using wet power vacuum street 
sweepers at least once per day. The use of dry power sweeping is prohibited. 

4. Water used to wash the various exposed surfaces (i.e., parkinq areas, staqinq areas, soil piles, qraded areas, 

etc.) will not be allowed to enter the water wav. 

5. All vehicle speeds on unpaved roads shall be limited to 15 mph. 

6. All roadways, driveways, and sidewalks to be paved shall be completed as soon as possible. Building pads 
shall be laid as soon as possible after grading unless seeding or soil binders are used. 

7. Idling times shall be minimized either by shutting equipment off when not in use or reducing the maximum 
idling time to 5 minutes (as required by the California airborne toxics control measure Title 13, Section 2485 of 
California Code of Regulations [CCR]). Clear signage shall be provided for construction workers at all access 
points. 

8. All construction equipment shall be maintained and properly tuned in accordance with manufacturer's 
specifications. All equipment shall be checked by a certified visible emissions evaluator. 

9. Post a publicly visible sign with the telephone number and person to contact at the lead agency regarding dust 
complaints. This person shall respond and take corrective action within 48 hours. The Air District's phone 
number shall also be visible to ensure compliance with applicable regulations. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-63 


December 2011 
Project 10.005 














2. Project Description 


BMP Number 

BMP Title 

BMP Description 

GEN-30 

Vehicle and Equipment 
Maintenance 

1. All vehicles and equipment will be kept clean. Excessive build-up of oil and grease will be prevented. 

2. All equipment used in the creek channel will be inspected for leaks each day prior to initiation of work. 
Maintenance, repairs, or other necessary actions will be taken to prevent or repair leaks, prior to use. 

3. Incoming vehicles and equipment (including delivery trucks, and employee and subcontractor vehicles) will be 
checked for leaking oil and fluids. Vehicles or equipment visibly leaking operational fluids will not be allowed 
on-site. 

4. No heavy equipment will operate in a live stream. This will not apply to activities for which no other option 
exists, such as sediment removal which cannot be conducted from top of bank, etc. In these cases, 
dewatering will be conducted as necessary, following the protocols in BMPs GEN-33 or GEN-34. 

5. No equipment servicing will be done in the creek channel or immediate floodplain, unless equipment stationed 
in these locations cannot be readily relocated (i.e., pumps and generators). 

6. If emergency repairs are required in the field, only those repairs necessary to move equipment to a more 
secure location, and that can be performed without releasing any material into the floodway or water, will be 
conducted in the channel or floodplain. 

7. If necessary, all servicing of equipment done at the job site will be conducted in a designated, protected area 
to reduce threats to water quality from vehicle fluid spills. Designated areas will not directly connect to the 
ground, surface water, or the storm drain system. The service area will be clearly designated with berms, 
sandbags, or other barriers. Secondary containment, such as a drain pan, to catch spills or leaks will be used 
when removing or changing fluids. Fluids will be stored in appropriate containers with covers, and properly 
recycled or disposed of offsite. 

GEN-31 

Vehicle Cleaning 

1. Equipment will be cleaned of any visible sediment or vegetation clumps before transferring and using in a 
different watershed to avoid spreading pathogens or exotic/invasive species. 

2. Vehicle and equipment washing can occur on-site only as needed to prevent the spread of sediment, 
pathogens or exotic/invasive species. No runoff from vehicle or equipment washing is allowed to enter water 
bodies, including creek channels and storm drains, without being subjected to adequate filtration (e.g., 
vegetated buffers, straw wattles or bales, fiber rolls, and silt screens). The discharge of decant water from any 
on-site wash area to water bodies or to areas outside of the active project site is prohibited. Additional 
vehicle/equipment washing will occur at the approved wash area in the District’s corporation yard. 

GEN-32 

Vehicle and Equipment 
Fueling 

1. No fueling will be done in the channel (top-of-bank to top-of-bank) or immediate floodplain unless equipment 
stationed in these locations cannot be readily relocated (e.g., pumps and generators). 

2. All off-site fueling sites (i.e., on access roads above the top-of-bank) will be equipped with secondary 
containment and avoid a direct connection to soil, surface water, or the storm drainage system. 

3. For stationary equipment that must be fueled on-site, secondary containment, such as a drain pan or drop 
cloth, will be used to prevent accidental spills of fuels from reaching the soil, surface water, or the storm drain 
system. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-64 


December 2011 
Project 10.005 









2. Project Description 


BMP Number 

BMP Title BMP Description 

Dewatering 

GEN-33 

Dewatering for Non-Tidal 
Sites 

When sediment removal and bank stabilization work area includes a flowing stream, the entire streamflow will be 
diverted around the work area by construction of a temporary dam and/or bypass. Where appropriate, stream flow 
diversions will occur via gravity driven systems. 

A. Planning to avoid and minimize impacts to water quality and aquatic wildlife: 

1. For construction and monitoring of a stream flow bypass, the Sediment Removal and Bank Stabilization 
Projects checklist will be completed. 

2. Recommendations by a qualified Fisheries Biologist to protect native fisheries and aquatic vertebrates will 
be incorporated into the bypass design. The recommendations may include but are not limited to: 

i. Screening the stream flow diversion source or pump to prevent entrainment of native fish or 
amphibian species. The screening dimensions will be appropriate to the species present. 

ii. Relocation of native aquatic vertebrates. This will include the methods to be used to capture and 
hold and move the aquatic vertebrates and a description of where the aquatic vertebrates will be 
relocated. 

3. Depending on the channel configurations, sediment removal activities may occur where the flows are not 
bypassed around the work site as long as a berm is left between the work area and stream flows to 
minimize water quality impacts during excavation activities. The berm between the work and the live 
channel will be wide enough to prevent introduction of turbid water from the cell into the live channel. 

B. Construction: 

1 . The construction of facilities will be based on the water bypass plan. 

2. Coffer dams will be installed both upstream and downstream of the work area to minimize impacts or the 
distance necessary to accomplish effective passive systems. 

3. In streams where water may enter the construction site from downstream (reverse flow) additional coffer 
dams (downstream) may be necessary. When multiple coffer dams are constructed, the upstream dam will 
be constructed first. 

4 . Sr Instream cofferdams will only be built from materials such as sandbaqs, earth fill, clean qravel, or rubber 
bladders which will cause little or no siltation or turbidity. 

5. 4 t Plastic sheeting will be placed over k-rails, timbers, and earth fill to minimize water seepage into and out 
of the maintenance areas. The plastic sheets will be firmly anchored, using sandbags, to the streambed to 
minimize water seepage. 

6 . When pumping is necessary to dewater a work site, a temporary siltation basin and/or use of silt bags may 
be required to prevent sediment from re-entering the wetted channel. Pump intakes will be screened to 
prevent harm to aquatic wildlife. 

7. If necessary to prevent erosion an energy dissipater will be constructed at the discharge point. 

8. Timing of flow diversions will be coordinated with the completion of the dam structure to facilitate not drying 
up the downstream creek area and to minimize dry back conditions. 



Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-65 


December 2011 
Project 10.005 









2. Project Description 


BMP Number 

BMP Title 

BMP Description 



C. Implementation: 

1. Water flows downstream of the project site will be maintained to prevent stranding aquatic vertebrates. 

2. Water diverted around work sites and water detained by coffer dams will be protected from maintenance 
activity-related pollutants, such as soils, equipment lubricants or fuels. 

3. The Fish Relocation Guidelines will be implemented to ensure that fish and other aquatic vertebrates are 
not stranded during construction and implementation of channel dewatering. 

a) Native aquatic vertebrates shall be captured in the work area and transferred to another reach as 
determined by a qualified biologist. Timing of work in streams that supports a significant number of 
amphibians will be delayed until metamorphosis occurs to minimize impacts to the resource. Capture 
and relocation of aquatic native vertebrates is not required at individual work sites when site 
conditions preclude reasonably effective operation of capture gear and equipment. 

b) Aquatic invertebrates will not be transferred (other than incidental catches) because of their 
anticipated abundance and colonization after completion of the repair work. 

4. Filtration devices (silt bags attached to the end of discharge hoses and pipes to remove sediment from 
discharged water) or settling basins will be provided as necessary at discharge sites to ensure that the 
turbidity of discharged water is not visibly more turbid than the water in the channel upstream of the 
maintenance site. If increases in turbidity are observed, additional measures will be implemented such as 
a larger settling basin or additional filtration. If increases in turbidity persist, the District’s Stream 
Maintenance Program Implementation Project Manager will be alerted since turbidity measurements may 
be required. 

5. Water remaining in the work area will be removed by evaporation, seepage, or pumping. When pumping is 
required to dewater a site, the decanted water will be discharged with water bypassed around the site or in 
a separate erosion control - energy dissipation area/vegetated swale. The turbidity of discharged water will 
not be visibly more turbid than the receiving water. 

Deconstruction: 

1. When maintenance is completed, the flow diversion structure will be removed as soon as possible. 

Impounded water will be released at a reduced velocity to minimize erosion, turbidity, or harm to downstream 
habitat. 

2. Removal will normally proceed from downstream in an upstream direction. 

3. When diversion structures are removed, the ponded water will be directed back into the low-flow channel in a 
phased manner to minimize erosion and downstream water quality impacts. Normal flows will be restored. 

4. The area disturbed by flow bypass mechanisms will be restored to the pre-project condition at the completion 
of the project (to the extent practical). This may include, but is not limited to, recontouring the area and 
planting of riparian vegetation. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-66 


December 2011 
Project 10.005 







2. Project Description 


BMP Number 

BMP Title 

BMP Description 

GEN-34 

Dewatering in Tidal Work 
Areas 

For tidal areas, a downstream cofferdam will be constructed to prevent the work area from being inundated by tidal 

flows. 

1. Installation of cofferdams and fish exclusion measures will be installed at low tide when the channel and project 
site are at their driest. 

2. It is preferable to not use any bypass pipes when work is being conducted on one side of the channel, jfs 
isolated by the cofferdam, and flows can continue on the other side of the creek channel without entering the 
project area. 

3. If downstream flows cannot be diverted around the project site, the creek waters will be transmitted around the 
site through cofferdam bypass pipes. Waters discharged through tidal cofferdam bypass pipes will not exceed 

50 NTUs over the background levels of the tidal waters into which they are discharged. 

4. Cofferdams in tidal areas may be made from earthen or gravel material. If earth is used, the downstream and 
upstream faces will be covered by a protected covering (e.g., plastic or fabric) if needed to minimize erosion. A 
protected covering or sheeting will be placed on the water side of an earthen coffer dam to protect water 
quality. 

5. When maintenance is completed, the cofferdams and bypass pipes will be removed as soon as possible but no 
more than 72 hours after work is completed. Flows will be restored at a reduced velocity to minimize erosion, 
turbidity, or harm to downstream habitat. 

GEN-35 

Pump/Generator Operations 
and Maintenance 

When needed to assist in channel dewatering, pumps and generators will be maintained and operated in a manner 

that minimizes impacts to water quality and aquatic species. 

1. Pumps and generators will be maintained according to manufacturers’ specifications to regulate flows to 
prevent dryback or washout conditions. 

2. Pumps will be operated and monitored to prevent low water conditions, which could pump muddy bottom 
water, or high water conditions, which creates ponding. 

3. All pump intakes will be screened. Pumps in steelhead creeks will be screened according to NMFS criteria 
(http://www.swr.noaa.gov/sr/fishscrn.pdf) to prevent entrainment of steelhead. 


Public Safety 


GEN-36 


Public Outreach 


The public will be informed of stream maintenance work prior to the start of work as part of the preparation of the 

NPW for all projects in the NPW: 

1. Each spring, a newspaper notice will be published with information on the NPW work sites, approximate work 
dates, and contact information. 

2. Neighborhood Work Notices will be distributed as part of the NPW preparation prior to the start of work. 

3. Local governments (cities and County) will be notified of scheduled maintenance work. The annua l work p l an 
NPW will be submitted to the public works departments, local fire districts, and the District’s Zon e Adv i sory 
Comm i tt ee Flood Protection and Watershed Advisory Committees . 

4. The District will post specific information on individual maintenance projects on the Stream Maintenance Web 
site: ( http://vallevwater.org/EkContent.aspx?id=379&terms=stream+maintenance ) 

5. For high profile projects, at the District’s discretion, signs will be posted in the neighborhood to notify the 
public at least one week in advance of maintenance schedules, trail closures, and road/lane closures as 
necessary and as possible. Signage used at work sites will include contact information for lodging comments 
and/or complaints regarding the maintenance activities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-67 


December 2011 
Project 10.005 

















2. Project Description 


BMP Number 

BMP Title 

BMP Description 

GEN-37 

Implement Public Safety 
Measures 

The District will implement public safety measures during maintenance as follows: 

1. Construction signs will be posted at job sites warning the public of construction work and to exercise caution, 
as appropriate to public accessed areas. 

2. Where work is proposed adjacent to a recreational trail, warning signs will be posted several feet beyond the 
limits of work. Signs will also be posted if trails will be temporarily closed. 

3. If needed, a lane will be temporarily closed to allow for trucks to pull into and out of access points to the work 
site. 

4. Temporary fencing, either the orange safety type or chain link, will be installed above repair sites on bank 
stabilization projects. 

5. When necessary, District or contracted staff will provide traffic control and site security. 

GEN-38 

Minimize Noise 

Disturbances to Residential 
Areas 

The District will implement maintenance practices that minimize disturbances to residential areas surrounding work 

sites. 

1. With the exception of emergencies, work will be conducted during normal working hours. Maintenance 
activities in residential areas will not occur on Saturdays, Sundays, or District observed holidays except during 
emergencies, or with approval by the local jurisdiction and advance notification of surrounding residents. 

2. Vehicles, generators and heavy equipment will be equipped with adequate mufflers. 

3. Idling of vehicles will be prohibited beyond 5 minutes unless operation of the engine is required to operate a 
necessary system such as a power take-off (PTO). 

GEN-39 

Planning for Pedestrians, 
Traffic Flow, and Safety 
Measures 

1. Work will be staged and conducted in a manner that maintains two-way traffic flow on public roadways in the 
vicinity of the work site. If temporary lane closures are necessary, they will be coordinated with the appropriate 
jurisdictional agency and scheduled to occur outside of peak traffic hours (7:00- 10:00 a.m. and 3:00 - 6:00 
p.m.) to the maximum extent practicable. Any lane closures will include advance warning signage, a detour 
route and flaggers in both directions. When work is conducted on public roads and may have the potential to 
affect traffic flow, work will be coordinated with local emergency service providers as necessary to ensure that 
emergency vehicle access and response is not impeded. 

2. Bicycle and pedestrian facility closures will be scheduled outside of peak traffic hours (7:00 - 10:00 a.m. and 
3:00 - 6:00 p.m.) to the maximum extent practicable. 

3. Public transit access and routes will be maintained in the vicinity of the work site. If public transit will be 
affected by temporary road closures and require detours, affected transit authorities will be consulted and kept 
informed of project activities. 

4. Adequate parking will be provided or designated public parking areas will be used for maintenance-related 
vehicles not in use through the maintenance period. 

5. Access to driveways and private roads will be maintained. If brief periods of maintenance would temporarily 
block access, property owners will be notified prior to maintenance activities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-68 


December 2011 
Project 10.005 









2. Project Description 


BMP Number | _ BMP Title _|_ BMP Description 

Cultural Resources 


GEN-40 


Discovery of Cultural 
Remains or Historic or 
Paleontological Artifacts 


Work in areas where remains or artifacts are found will be restricted or stopped until proper protocols are met. 

1. Work at the location of the find will halt immediately within 50 feet of the find. A “no work” zone shall be 

established utilizing appropriate flagging to delineate the boundary of this zone, which shall measure at least 
50 feet in all directions from the find. 

2. The District shall retain the services of a Consulting Archaeologist or Paleontologist, who shall visit the discovery 

site as soon as practicable, and perform minor hand-excavation to describe the archaeological or 
paleontological resources present and assess the amount of disturbance. 

3. The Consulting Archaeologist shall provide to the District and the Corps, at a minimum, written and digital- 

photographic documentation of all observed materials, utilizing the guidelines for evaluating archaeological 
resources for the California Register of Historic Places (CRHP) and National Register of Historic Places 
(NRHP). Based on the assessment, the District and Corps shall identify the CEQA and Section 106 cultural- 
resources compliance procedure to be implemented. 

4. If the find appears to not meet the CRHP or NRHP criteria of significance, and the Corps archaeologist concurs 

with the Consulting Archaeologist’s conclusions, construction shall continue while monitored by the Consulting 
Archaeologist. The authorized maintenance work shall resume at the discovery site only after the District has 
retained a Consulting Archaeologist to monitor and the Watershed Manager has received notification from the 
Corps to continue work. 

5. If the find appears significant, avoidance of additional impacts is the preferred alternative. The Consulting 

Archaeologist shall determine if adverse impacts to the resources can be avoided. 

6. When avoidance is not practical (e.g., maintenance activities cannot be deferred or they must be completed to 

satisfy the SMP objective), the District shall develop an Action Plan and submit it to the Corps within 48 hours 
of Consulting Archaeologist’s evaluation of the discovery. The action Plan may be submitted via e-mail to 
{rstradford@spd.usace.army.mil}. The Action Plan is synonymous with a data-recovery plan. It shall be 
prepared in accordance with the current professional standards and State guidelines for reporting the results of 
the work, and shall describe the services of a Native American Consultant and a proposal for curation of 
cultural materials recovered from a non-grave context. 

7. The recovery effort will be detailed in a report prepared by the archaeologist in accordance with current 

archaeological standards. Any non-grave artifacts will be placed with an appropriate repository. 

8. The Consulting Paleontologist will meet the Society for Vertebrate Paleontology’s criteria for a “qualified 

professional paleontologist” (Society of Vertebrate Paleontology Conformable Impact Mitigation Guidelines 
Committee 1995). 

9. The paleontologist will follow the Society for Vertebrate Paleontology’s guidelines for treatment of the artifact. 

Treatment may include preparation and recovery of fossil materials for an appropriate museum or university 
collection, and may include preparation of a report describing the finds. The District will be responsible for 
ensuring that paleontologist’s recommendations are implemented. 

10. In the event of discovery of human remains (or the find consists of bones suspected to be human), the field 
crew supervisor shall take immediate steps to secure and protect such remains from vandalism during periods 
when work crews are absent.) 

11. Immediately notify the Santa Clara County Coroner and provide any information that identify the remains as 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-69 


December 2011 
Project 10.005 








2. Project Description 


BMP Number 

BMP Title 

BMP Description 



Native American. If the remains are determined to be from a prehistoric Native American, or determined to be a 
Native American from the ethnographic period, the Coroner shall contact the Native American Heritage 
Commission (NAHC) within 24 hours of being notified of the remains. The NAHC then designates and notifies 
within 24 hours a Most Likely Descendant (MLD). The MLD has 24 hours to consult and provide 
recommendations for the treatment or disposition, with proper dignity, of the human remains and grave goods. 

12. Preservation in situ is the preferred option. Human remains shall be preserved in situ if continuation of the 

maintenance work, as determined by the Consulting Archaeologist and MLD, will not cause further damage to 
the remains. The remains and artifacts shall be documented and the find location carefully backfilled (with 
protective geo-fabric if desirable) and recorded in District project files. 

13. Human remains or cultural items exposed during maintenance that cannot be protected from further damage 

shall be exhumed by the Consulting Archaeologist at the discretion of the MLD and reburied with the 
concurrence of the MLD in a place mutually agreed upon by all parties. 

GEN-41 

Review of Projects with 
Native Soil 

A cultural resources specialist will conduct a review and evaluation of those sites that would involve disturbance / 
excavation of native soil previously undisturbed by contemporary human activities to determine their potential for 
affecting significant cultural resources. The evaluation of the potential to disturb cultural resources will be based on 
an initial review of archival information provided by the California Historical Resources System/Northwest 
Information Center (CHRIS/NWIC) in regard to the project area based on a 0.25 mile search radius. It is 
recommended that this initial archival review be completed by a professional archaeologist who will be able to view 
confidential site location data and literature to arrive at a preliminary sensitivity determination. If necessary, a 
further archival record search and literature review (including a review of the Sacred Lands Inventory of the Native 
American Heritage Commission); and a field inventory of the project area will be conducted to determine the 
presence/absence of surface cultural materials associated with either prehistoric or historic occupation. The results 
along with any mitigation and/or management recommendations would be presented in an appropriate report 
format and include any necessary maps, figures, and correspondence with interested parties. A summary table 
indicating appropriate management actions (e.g., monitoring during construction, presence/absence testing for 
subsurface resources; data recovery, etc.) will be developed for each project site reviewed. The management 
actions will be implemented on site to avoid significant effects to cultural resources. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-70 


December 2011 
Project 10.005 








2. Project Description 


BMP Number 

BMP Title 

BMP Description 

Utilities 



GEN-42 

Investigation of Utility Line 
Locations 

An evaluation of the locations of utility lines that could be affected by maintenance activities will be conducted 
annually as part of the preparation of the Notice of Proposed Work (NPW). Utilities will be avoided as much as 
possible. For maintenance areas with the potential for adverse effects on utility services, the following measures 
shall be implemented: 

1. Utility excavation or encroachment permits shall be required from the appropriate agencies. These permits 
include measures to minimize utility disruption. The District and its contractors shall comply with permit 
conditions. Such conditions shall be included in construction contract specifications. 

2. Utility locations shall be verified through a field survey (potholing) and use of the Underground Service Alert 
services. 

3. Detailed specifications shall be prepared as part of the design plans to include procedures for the excavation, 
support, and/or fill of areas around utility cables and pipelines. All affected utility services shall be notified of the 
District’s maintenance plans and schedule. Arrangements shall be made with these entities regarding 
protection, relocation, or temporary disconnection of services. 

4. Residents and businesses in the project area shall be notified of planned utility service disruption 2 to 4 days in 
advance, in conformance with state standards. 

5. Disconnected cables and lines shall be reconnected promptly. 


SECTION C - Sediment Removal BMPs 

This group of BMPs is intended to be implemented specifically during sediment removal activities^ Tto avoid potential impacts on biological 
resources , non e of th e s e m e asur e s w ill b e i mp le m e nt e d unt il author i zat i on from th e SMP I mp le m e ntat i on Proj e ct Manag e r i s r e c ei v e d . 


BMP Number 

BMP Title 

BMP Description 

SED-1 

Groundwater Management 

If high levels of groundwater (i.e., visible water) are encountered during excavations in a work area, the water will 
be pumped out of the work site or left within the work area if the work activity is not causing water quality 
degradation in a live stream. Water Quality monitoring would need to occur. If necessary to protect water quality, 
the extracted water will be discharged into specifically constructed infiltration basins, holding ponds, or areas with 
vegetation to remove sediment prior to the water re-entering a creek. Water discharged into vegetated areas or 
swales will be pumped in a manner that will not create erosion around vegetation. 

SED-2 

Prevent Scour Downstream 
of Sediment Removal 

Sediment removal sites in the transport zone on alluvial fans may cause increased scour downstream if they 
experience scouring flows or rapid sediment accumulation after maintenance. 

After sediment removal, the channel will be graded so that the transition between the existing channel both 
upstream and downstream of the maintenance area is smooth and continuous between the maintained and non- 
maintained areas and does not present a sudden vertical transition (wall of sediment) or other blockage that could 
erode once flows are restored to the channel. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-71 


December 2011 
Project 10.005 














2. Project Description 


BMP Number 

BMP Title 

BMP Description 

SED-3 

Restore Channel Features 

Low-flow channels within non-tidal streams will be contoured to facilitate fish passage and will emulate the pre¬ 
construction conditions as closely as possible, within the finished channel topography. 

SED-4 

Berm Bypass 

Where sediment removal is accomplished without a bypass by removing alternating cells, the berm between the 
work and the live channel will be wide enough to prevent introduction of turbid water from the cell into the live 
channel. 


SECTION D - Vegetation Management BMPs 

These BMPs provide specific and detailed guidance on the variety of vegetation management procedures implemented by the District. BMPs for 
the following maintenance techniques are included: tree pruning, tree removal, plant removal, woody debris management, herbicide application, 
mowing, discing, flaming, and grazing. Practices will be implemented by fully trained and qualified field crews. 


BMP Number 


BMP Title 


BMP Description 


VEG-1 

Minimize Local Erosion 
Increase from In-channel 
Vegetation Removal 

To minimize the potential effect of localized erosion, the toe of the bank will be protected by leaving vegetation to 
the maximum extent possible and consistent with the maintenance guidelines or original design requirements. 

VEG-2 

Non-native Invasive Plant 
Removal 

Invasive species (e.q. cape ivv f Delairea odorata/Senecio mikanoidesl arundo f Arundo donax 1) will be disposed of 
in a manner that will not contribute to the further spread of the species. Cape ivy removed during a project shall be 
baaaed and disposed of in a landfill. Arundo canes will be prevented from floatina downstream or otherwise 
enterina the creek or waterway. 

VEG-3 

Use Appropriate Equipment 
for Instream Removal 

When using heavy equipment to cut or remove instream vegetation, low ground pressure equipment, such as 
tracked wheels will be utilized to reduce impacts to the streambed. 

VEG-4 

Use Flamers with Caution 

1. A fire extinguisher, water supply and other appropriate fire suppression equipment will always be kept close to 
the work site in case of an emergency. 

2. Propane tanks will be checked for leaks and proper functioning prior to and proceeding use of flaming 
equipment. The propane tank will be treated as a hazardous material. 

VEG-5 

Conduct Flaming During 
Appropriate Weather and 
Seasonal Conditions 

Flamers will not be used during periods of high fire danger or in areas where fuel or climate conditions could 
accidentally ignite a fire. 

VEG-6 

Standard Grazing 
Procedures 

1. Vegetation and areas to be preserved will be fenced off to exclude grazing animals. 

2. Grazing animals will be excluded from stream channels, using fencing or other barriers. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-72 


December 2011 
Project 10.005 
























2. Project Description 


SECTION E - Bank Stabilization BMPs 

These BMPs provide additional guidance during implementation of bank stabilization projects^^Pto avoid impacts on biological and cultural 
resources , non e of th e s e m e asur e s w ill b e i mp le m e nt e d unt il author i zat i on from th e SMP I mp le m e ntat i on Proj e ct Manag e r i s r e c ei v e d . Review of 
the Post-Project Restoration BMPs in Section F is recommended because those measures will be implemented after bank stabilization projects 
are complete. The BMPs included in this section are implemented by the field crew and site manager. 


BMP Number 

BMP Title 

BMP Description 

BANK-1 

Bank Stabilization Design to 
Prevent Erosion 

Downstream 

To further prevent potential downstream erosion impacts due to bank stabilization, the site design will be adjusted 
to provide proactive protection of vulnerable areas within the reach of the worksite. Such measures include, but 
are not limited to, appropriately keyed-in coir logs, riparian planting, strategic placement of rock, and flow 
deflectors. 

Bank stabilization will include appropriate transition designs upstream and downstream of the work site to prevent 
potential erosion impacts. 

BANK-2 

Concrete Use Near 
Waterways 

Concrete that has not been cured is alkaline and can increase the pH of the watery fFresh concrete will be isolated 
until it no longer poses a threat to water quality using the following appropriate measures: 

1. Wet sacked concrete will be excluded from the wetted channel for a period of two weeks after installation. 

During that time, the wet sacked concrete will be kept moist (such as covering with wet carpet) and runoff from the 
wet sacked concrete will not be allowed to enter a live stream. 

2. Poured concrete will be excluded from the wetted channel for a period of two weeks after it is poured. During 
that time, the poured concrete will be kept moist, and runoff from the wet concrete will not be allowed to enter a 
live stream. Commercial sealants (e.g., Deep Seal, Elasto-Deck Reservoir Grade) may be applied to the poured 
concrete surface where difficulty in excluding water flow for a long period may occur. If a sealant is used, water will 
be excluded from the site until the sealant is dry. 

3. Dry sacked concrete will not be used in any channel. 

4. An area outside of the channel and floodplain will be designated to clean out concrete transit vehicles. 

BANK-3 

Bank Stabilization Post- 
Construction Maintenance 

The District may maintain or repair bank stabilization projects that are less than 2 years old that are damaged by 
winter flows. 

The District will notify the regulatory agencies 24 hours prior to beginning the work and the work will be reported as 
part of the Post-Construction Report submitted by January 15 of each year or if necessary, the subsequent year. 
Appropriate BMPs will be applied during maintenance repairs. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-73 


December 2011 
Project 10.005 










2. Project Description 


SECTION F - Post-Project Restoration BMPs 


These BMPs will be implemented, as appropriate, on all sites that involve ground disturbance. 


BMP Number 

BMP Title 

BMP Description 

REVEG-1 

Seeding 

Sites where maintenance activities result in exposed soil will be stabilized to prevent erosion. Disturbed areas shall 
be seeded with native seed as soon as is appropriate after maintenance activities are complete. An erosion control 
seed mix may be applied to exposed soils, and down to the ordinary high water mark (OHWM). 

1. The seed mix should consist of California native grasses (e.g., Hordeum brachyantherum, Elymus glaucus , and 
Vulpia microstachyes) or annual, sterile seed mix. 

2. Temporary earthen access roads may be seeded when site and horticultural conditions are suitable, or have 
other appropriate erosion control measures in place (GEN-20). 

REVEG-2 

Planting Material 

Revegetation and replacement plantings will consist of locally collected native species. Species selection will be 
based on surveys of natural areas on the same creek that have a similar ecological setting and/or as appropriate 
for the site location. 


SECTION G - Management of Animal Damag e Conflict BMPs 

Methods of animal management included in the SMP are avoidance, biological controls, physical alterations, habitat alterations, and lethal 
controls. Of all these methods, implementation of lethal controls has the highest potential for environmental and biological impacts. Therefore, the 
animal management BMPs provided in this section focus on lethal controls. The application area for lethal controls will be identified during the 
annual planning process (see the Biological Resource Planning BMPs) and guided as directed by wildlife biologists. Species habitat areas are 
defined by the District’s GIS species mapping, updated CNDDB and known local biological information and are included in the SMP Update 
Subsequent EIR. 


BMP Number 

BMP Title 

BMP Description 

ANI-1 

Avoid Redistribution of 
Rodenticides 

Carcass surveys will be conducted periodically when acute poisons and first qeneration anticoaqulants are used. 

The frequency of the carcass surveys will be specific to the type of rodenticide used In areas where rodenticides 

are used, carcass retrieval surveys will be conducted as follows to minimize secondary poisoninq impacts; 

• Acute toxins-Dailv, carcass surveys, beqinninq the first dav after application until the end of the baitinq 
period for acute toxins used above-qround . 

• Anticoaqulants-Weeklv for anticoaquIantsWithin 7 davs of installation of first qeneration anticoaqulant 
bait, and weekly thereafter. Anytime a carcass is found, daily carcass surveys will beqin for as lonq as 

carcasses are found until no carcasses are found durinq a daily survey. Once no carcasses are found, 

carcass surveys will return to the weekly carcass survey timeline maximum from the date of initial 

installation of an anticoaqulant bait station. 

. In addition, twice per year District biologists will conduct daily carcass surveys for a full cycle of a baiting trap. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-74 


December 2011 
Project 10.005 































2. Project Description 


BMP Number 

BMP Title 

BMP Description 



to minimize secondary poisoninq impacts. To verify that the freauencv of carcass surveys is adeauate, a bioloaist 
will conduct daily carcass surveys 2 times per vear over one baitinq cvcle. Based on the results of these surveys. 

the timinq of carcass surveys will be adjusted if necessary. 

Any spilled bait will be cleaned up immediately. 

AN 1-2 

Prevent Harm to the Salt 
Marsh Harvest Mouse and 
California Clapper Rail 

1. No rodenticides or fumigants will be used within the range of the SMHM or CCR as identified on District range 
maps. 

2. Methods of rodent control within SMHM or CCR habitat will be limited to live trapping. All live traps shall have 
openings measuring no smaller than 2 inches by 1 inch to allow any SMHM that inadvertently enter the trap to 
easily escape. All traps will be placed outside of pickleweed areas and above the high tide line. 

ANI-3 

Burrowing Owl, Bald Eagle 
and Golden Eagle Buffer 
Zone 

Per the California Department of Fish and Game’s 2008 Guidance for Burrowing Owl Conservation, a 656-yard 
buffer will be established around known burrowing owl locations where no rodenticides or fumigants (including 
smoke bombs) will be used. A 0.5-mile buffer will be established around known bald eagle and golden eagle 
nesting locations where no rodenticides will be used. 

AN 1-4 

Animal Control in Sensitive 
Amphibian Habitat 

1. Fumigants will not be used within the habitat areas of special status amphibians. 

2. The use of bait stations within the potential habitat areas of California red-legged frog, California tiger 
salamander, or foothill yellow-legged frog will be limited to bait stations specifically designed to prevent entry by 
these species. 

3. Any live traps will allow California red-legged frogs, California tiger salamanders, or foothill yellow-legged frogs 
to safely exit (e.g., by having openings measuring no smaller than 2 inches by 1 inch). 

ANI-5 

Slurry Mixture near 
Waterways 

All slurry type mixes used to fill rodent burrows will be prevented from entering any waterway by using appropriate 
erosion control methods and according to the manufacturer’s specifications. If the creek bed is dry or has been 
dewatered, any material that has entered the channel will be removed. 


SECTION H - Use of Pesticides 

Pesticides may be used for vegetation management or control of animal damage 


BMP Number 

BMP Title 

BMP Description 

HM-4 

Posting and Notification for 
Pesticide Use 

Posting of areas where pesticides are used will be performed in compliance with District Policy Ad-8.2 Pesticide 

Use as follows: 

1. Posting will be performed in compliance with the label requirements of the product being applied. 

2. In addition, posting will be provided for any products applied in areas used by the public for recreational 
purposes, or those areas readily accessible to the public, regardless of whether the label requires such notification. 
In doing this, the District ensures that exposure risk is minimized further by adopting practices that go beyond the 
product label requirements. (The posting method may be modified to avoid destruction of bait stations or scattering 
of rodenticide.) 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-75 


December 2011 
Project 10.005 



















2. Project Description 


BMP Number 

BMP Title 

BMP Description 



3. These postings will notify staff and the general public of the date and time of application, the product’s active 
ingredients, and common name, and the time of allowable re-entry into the treated area. 

4. Signs will not be removed until after the end of the specified re-entry interval. 

5. Right-to-know literature on the product will be made available to anyone in the area during the re-entry period. 

6. A District staff contact phone number will be posted on the siqn, includinq a paqercellular phone number. 

7. Notification of pesticide activities will be made as required by law. Also, the District will maintain records of 
neighbors with specific needs relative to notification before treatment of an adjacent area so that such needs are 
met. 


Source: Data compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


2-76 


December 2011 
Project 10.005 








s:/2010/Horizon/SCVWD/GIS/Layouts/Fig2 LowerPeninsula.mxd (02.01.11) mg 



Horizon Figure 2-2: Project Area 

Lower Peninsula Watershed 



















This page intentionally left blank. 



:/2010/Horizon/SCVWD/GIS/Lavouts/Fig2 Westside.mxd (02.01.11) mg 



Horizon Figure 2-3: Project Area 

West Valley Watershed 





















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/Fig2 Guadalupe.mxd (02.01.11) mg 



Horizon Figure 2-4: Project Area 

Guadalupe Watershed 

















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/Fig2 Coyote.mxd (12.15.11) mg 



OL Horizon 

W WAltR ind ENVlRONMI 


Figure 2-5: Project Area 
Coyote Watershed 






















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/Fig2 Pajaro.mxd (08.25.10) mg 



Horizon Figure 2-6: Project Area 

Pajaro Watershed 
















This page intentionally left blank. 



UpperTop of Bank 


PRE - MAINTENANCE CONDITION 
SMP Channel Type: Wide and Complex 



Top of Bank 


UpperTop of Bank 



Top of Bank 


Note 1 - for flood control channels that include engineered levees, the upper bank portion of this typical cross section is analogous to the inboard levee. Many SCVWD levees also have a 
visible outboard slope that slopes outside and away from the channel to the adjacent land. 

Note 2 - the areas in the typical cross-section identified as "bank" or "bench" are typically combined into a single geographic area type "bank/bench" for the purposes of SCVWD maintenance 
work projections. 


0L Horizon 

V ^ WAi tR and ENVIRONMENT 


Figure 2-7 

Example of SCVWD-Maintained Channel 




















This page intentionally left blank. 



10.005 (1-2011) JD 


Top of Levee 


Interior 

Bank 


Top of Levee 


Levee 

Outboard 


Levee 

Outboard 



Vegetation 
Free Zone 


Vegetation 
Free Zone 


^Although in some instances vegetation exists at levee inboard locations, 
for federally-constructed flood protection projects for which SCVWD is 
the local sponsor (and therefore responsible for maintenance), the 
U.S. Army Corps of Engineers (Corps) has indicated that vegetation-free 
zones should exist at levee inboard locations to maximize accessibility for 
inspection and maintenance (unless the local sponsor applies for and 
receives a vegetation variance from the Corps). 


Horizon 

^ ^ WAI fck and ENVIRONMENT 


Figure 2-9 

Typical Wide Channel Cross Section with Secondary Channel 















■queiq qjaj Xueuopusiui sSed siqj. 



10.005 (1-2011) JD 



Fence 


b) Trapezoidal Channel with Earthen Bed and Bank 



Fence 


>: 

x 

>: 

Top of Bank >; 

Gravel 
Access 
Road 


Maintained 

Grass-Lined 

Banks 


Channel Bed 


Bankfull Channel 
Height 


Horizon 

^ „ A CMUIDAM) 


WATER and ENVIRONMENT 


Figure 2-11 
Typical Trapezoidal Channels 










This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/LowerPeninsula_Sediment.mxd (11.15.11) mg 



Horizon Figure 2-14: Lower Peninsula Watershed Maintenance 

..Activity - Sediment Removal 

















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/LavoutsA/VateshedActivityA/VestVallev sediment.mxd (11.15.11) mg 



Horizon Figure 2-15: West Valley Watershed Maintenance 

. .. Activity - Sediment Removal 














This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/Guadalupe_Sediment.mxd (11.15.11) mg 



Alviso 


Santa 

Clara 


Campbell 


Edenvale 


Cambrian 

Park 


Alamitos 


Vasona 

teservoip' 


Los 

Gatos 


C &Dal 


Caj^ro"' 

Reservoir 


.-^erbeju 


Pajaro 


Horizon 


Figure 2-16: Guadalupe Watershed Maintenance 

Activity - Sediment Removal 


Santa 

Clara 

County 


Detail 

Area 


- Watershed Boundaries 


Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


Major Roads 

Upper Elevation Boundary of SMP 


I Miles 


Sediment Removal: 2002 - 2012 (only) 

Sediment Removal: 2002 - 2012 and 2012-2022 (both) 
Sediment Removal: 2012 - 2022 (new) 

County Boundary 
Streams 


1 inch = 3.5 miles 


Note: Project area maps provide a general 
description of work type and area for the 
2012-2022 SMP Update and are not intended 
to represent the exact locations of future work. 
















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/LavoutsA/VateshedActivitv/CoyoteSediment.mxd (11.15.11) mg 



Santa 

Clara 

County 




Detail 

Area 


Pacific 

Ocean 


Horizon 

V wa* **« 5*1?**" 


m Sediment Removal: 2002 - 2012 (only) 

Sediment Removal: 2002 - 2012 and 2012-2022 (both) 
Sediment Removal: 2012 - 2022 (new) 

- County Boundary 

Streams 

— (#) — Major Roads 
- Upper Elevation Boundary of SMP 


Note: Project area maps provide a general 
description of work type and area for the 
2012-2022 SMP Update and are not intended 
to represent the exact locations of future work. 

1 inch = 5 miles 



0 


1.5 


Miles 


3 6 


- Watershed Boundaries 


Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


Figure 2-17: Coyote Watershed Maintenance 
Activity - Sediment Removal 






















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Lavouts/WateshedActivity/Paiaro Sediment.mxd (03.28.11) mg 



t Horizon 

v W MOW fl IVY f CMKt 


Figure 2-18: Pajaro Watershed Maintenance 
Activity - Sediment Removal 


















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/LowerPeninsula_OtherVeg.mxd (11.15.11) mg 



Horizon Figure 2-19: Lower Peninsula Watershed Maintenance Activity 

. .Other Instream Vegetation Maintenance 





















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Lavouts/WateshedActivity/WestVallev OtherVeg.mxd (11.15.11) mg 



Horizon Figure 2-20: West Valley Watershed Maintenance Activity 

. .Other Instream Vegetation Maintenance 















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/Frequency/Guadalupe.mxd (10.24.11) mg 



Horizon Figure 2-21: Guadalupe Watershed Maintenance Activity 

Other Instream Vegetation Maintenance 
















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/LavoutsA/VateshedActivitv/Coyote OtherVeg.mxd (11.15.11) mg 



Horizon 


Figure 2-22: Coyote Watershed Maintenance Activity 
Other instream Vegetation Maintenance 




















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Lavouts/WateshedActivitv/Pajaro OtherVeg.mxd (4.11.11) mg 



Pacific \ 
Ocean 



Other Instream Vegetation Maintenance Activity: 2002 - 2012 (only) 

Other Instream Vegetation Maintenance Activity: 2002 - 2012 and 2012-2022 (both) 
Other Instream Vegetation Maintenance Activity: 2012 - 2022 (new) 

- County Boundary - Upper Elevation Boundary of SMP 

Streams - Watershed Boundaries 

—(#)— Major Roads 


Notes: Other Instream Vegetation Maintenance includes hand pruning, hand removal, and mowing. 

Project area maps provide a general description of work type and area for the 2012-2022 SMP U l.o o o 

Update and are not intended to represent the exact locations of future work. Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


& Horizon 

v W MOW •»« IVY f CMKI VT 


Figure 2-23: Pajaro Watershed Maintenance Activity 
Other Instream Vegetation Maintenance 















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/LowerPeninsula_OtherVeg.mxd (11.15.11) mg 



Horizon Figure 2-24: Lower Peninsula Watershed Maintenance Activity 

..Other Non-Instream Vegetation Maintenance 
















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Lavouts/WateshedActivity/WestVallev OtherVeg.mxd (11.15.11) mg 



Horizon Figure 2-25: West Valley Watershed Maintenance Activity 

..Other Non-Instream Vegetation Maintenance 

















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/Frequency/Guadalupe.mxd (11.16.11) mg 



Other Non-Instream Vegetation Maintenance Activity: 2002 - 2012 (only) 


Santa 

Clara 

County 

Detail 
Area 



Other Non-Instream Vegetation Maintenance Activity: 2002 - 2012 and 2012-2022 (both) 

Other Non-Instream Vegetation Maintenance Activity: 2012 - 2022 (new) 

County Boundary - Upper Elevation Boundary of SMP 

Streams - Watershed Boundaries 1 inch = 3.5 miles 



Pacific 

Ocean 


—(#)— Major Roads 

Note: Other Non-Instream Vegetation Maintenance includes hand pruning, hand removal 
and mowing. Project area maps provide a general description of work type and are for the 2012- 


I Miles 


0 12 4 

2022 SMP Update and are not intended to represent the exact locations of futuij&yw&ksanta Clara Valley Water District, 2010; ESRI Roads, 2010 


Horizon 


Figure 2-26: Guadalupe Watershed Maintenance Activity 
Other Non-Instream Vegetation Maintenance 



















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/LavoutsA/VateshedActivitv/Coyote OtherVeg.mxd (11.15.11) mg 



Horizon 


Figure 2-27: Coyote Watershed Maintenance Activity 
Other Non-instream Vegetation Maintenance 




















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Lavouts/WateshedActivitv/Pajaro OtherVeg.mxd (4.11.11) mg 



Pacific \ 
Ocean 



Other Non-Instream Vegetation Maintenance Activity: 2002 - 2012 (only) 

Other Non-Instream Vegetation Maintenance Activity: 2002 - 2012 and 2012-2022 (both) 
Other Non-Instream Vegetation Maintenance Activity: 2012 - 2022 (new) 

- County Boundary - Upper Elevation Boundary of SMP 

Streams - Watershed Boundaries 

—(#)— Major Roads 

Notes: Other Non-Instream Vegetation Maintenance includes discing, hand pruning, hand removal, 
and mowing. Project area maps provide a general description of work type and area for the 2012- 
2022 SMP Update and are not intended to represent the exact locations of future work. 


0 1.5 3 6 

Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


& Horizon 

v W MOW •»« IVY f CMKI VT 


Figure 2-28: Pajaro Watershed Maintenance Activity 
Other Non-Instream Vegetation Maintenance 















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/LowerPeninsula_Herbicide.mxd (11.16.11) mg 



i Coyote 


Lagunita 


Los 

Altos 


Los 

Altos 

Hills 


Foothill 

Park 


#PermangjJ^^ 

[Diversion Channel 


Pennant 


Pacific 


Horizon 

«6**iFnT 


Figure 2-29: Lower Peninsula Watershed Maintenance Activity 

Instream Herbicide Application 


Santa 

Clara 

County 


Instream Herbicide Application: 2002 - 2012 (only) 

Instream Herbicide Application: 2002 - 2012 and 2012-2022 (both) 
Instream Herbicide Application: 2012 - 2022 (new) 


County Boundary 
Streams 

—(#)— Major Roads 


Upper Elevation Boundary of SMP 
Watershed Boundaries 


1 inch = 2.15 miles 
I Miles 


Note: Instream application occurs below the bankfull channel elevation. Project area maps 
provide a general description of work type for the 2012-2022 SMP Update and are 

not intended to represent the exact locations of future work. Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 

















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Lavouts/WateshedActivityA/Vestside.mxd (11.16.11) mg 



Horizon Figure 2-30: West Valley Watershed Maintenance Activity 

. .Instream Herbicide Application 















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/Guadalupe_Herbicide.mxd (11.16.11) mg 



Alviso 


Santa 

Clara 


Campbell 


Edenvale 


Cambrian 

Park 


Alamitos 


I Jvasona 
'Reservok 


Los 

Gatos 


Cana/ 


Caj^ro"' 

teservoir 


j^erb 


Pajaro 


Horizon 

wi*T¥ **T 


Figure 2-31: Guadalupe Watershed Maintenance Activity 

Instream Herbicide Application 


Santa 

Clara 

County 


Detail 

Area 


Instream Herbicide Application: 2002 ■ 
Instream Herbicide Application: 2002 ■ 
Instream Herbicide Application: 2012 ■ 


2012 (only) 

2012 and 2012-2022 (both) 
2022 (new) 




County Boundary 
Streams 
Major Roads 


Upper Elevation Boundary of SMP 
Watershed Boundaries 


1 inch = 3.5 miles 


_I Miles 

Note: Instream application occurs below the bankfull channel elevation. Project area maps 
provide a general description of work type for the 2012-2022 SMP Update and are 
not intended to represent the exact locations of future work. Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/LavoutsA/VateshedActivitv/Coyote Herbicide.mxd (11.16.11) mg 



Santa 

Clara 

County 


m 


Detail 

Area 


Instream Herbicide Application: 2002 - 2012 (only) 

Instream Herbicide Application: 2002 - 2012 and 2012-2022 (both) 
Instream Herbicide Application: 2012 - 2022 (new) 

County Boundary - Upper Elevation Boundary of SMP 

Streams -Watershed Boundaries 


e 

1 inch = 5 miles 


Pacific 

Ocean 


I Miles 


—(#)— Major Roads 

Note: Instream application occurs below the bankfull channel elevation. Project area maps 
provide a general description of work type for the 2012-2022 SMP Update and are 
not intended to represent the exact locations of future work. Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


0 1 


Horizon 


Figure 2-32: Coyote Watershed Maintenance Activity 

Instream Herbicide Application 





















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Lavouts/WateshedActivity/Paiaro Herbicide.mxd (04.10.11) mg 



Pacific 

Ocean 



m Instream Herbicide Application: 2002 - 2012 (only) 

Instream Herbicide Application: 2002 - 2012 and 2012-2022 (both) 

^■ Instream Herbicide Application: 2012 - 2022 (new) 

- County Boundary - Upper Elevation Boundary of SMP 

Streams - Watershed Boundaries 

—(#)— Major Roads 

Notes: Instream application occurs below the bankfull channel elevation. Project area maps 
provide a general description of work type and area for the 2012- 2022 SMP Update and are not 
intended to represent the exact locations of future work. 


0 1.5 3 6 

Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


& Horizon 

v W MOW •»« IVY •CMKIVT 


Figure 2-33: Pajaro Watershed Maintenance Activity 

Instream Herbicide Application 















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/LowerPeninsula_Herbicide.mxd (11.16.11) mg 



Horizon 


Figure 2-34: Lower Peninsula Watershed Maintenance Activity 

Non-Instream Herbicide Application 


















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/LavoutsA/VateshedActivityA/Vestside.mxd (11.16.11) mg 



Horizon Figure 2-35: West Valley Watershed Maintenance Activity 

. . l ”* W5r Non-Instream Herbicide Application 



















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/Guadalupe_Herbicide.mxd (11.16.11) mg 



Alviso 


Santa 

Clara 


Campbell 


Edenvale 


Cambrian 

Park 


Alamitos 


vasona 

leservok 


Lo's 

Gatos 


ca^a/ 


■c^ 

teservoir 


j^erb 


Horizon 


Figure 2-36: Guadalupe Watershed Maintenance Activity 

Non-Instream Herbicide Application 


Santa 

Clara 

County 


Detail 

Area 




Non-Instream Herbicide Application: 2002 - 2012 (only) 

Non-Instream Herbicide Application: 2002 - 2012 and 2012-2022 (both) 
Non-Instream Herbicide Application: 2012 - 2022 (new) 

County Boundary 
Streams 
Major Roads 


- Upper Elevation Boundary of SMP 

- Watershed Boundaries 


1 inch = 3.5 miles 


I Miles 


Note: Non-Instream application occurs below the bankfull channel elevation. Project area maps 
provide a general description of work type for the 2012-2022 SMP Update and are 0 12 4 

not intended to represent the exact locations of future work. Source: Santa c|ara Va||ey Water Districti 2010; ESRI Roads 2010 




















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/WateshedActivity/Coyote Herbicide.mxd (11.16.11) mg 



Milpitas 


Co^otei 


• ADdersm 
«fi» Lake 


/•—Madrone 


[W atershed 


Morgan 

n 


Monterey 

Bay 


Pacific 


Horizon 

waHi 


Figure 2-37: Coyote Watershed Maintenance Activity 
Non-Instream Herbicide Application 


Non-lnstream Herbicide Application: 2002 - 2012 (only) 

Non-Instream Herbicide Application: 2002 - 2012 and 2012-2022 (both) 
Non-lnstream Herbicide Application: 2012 - 2022 (new) 


- County Boundary 

Streams 

—(#)— Major Roads 


Upper Elevation Boundary of SMP 
Watershed Boundaries 


1 inch = 5 miles 
I Miles 


Note: Non-lnstream application occurs below the bankfull channel elevation. Project area maps 
provide a general description of work type for the 2012-2022 SMP Update and are 
not intended to represent the exact locations of future work. Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


Santa 

Clara 

County 


m 


Detail 

Area 




















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Lavouts/WateshedActivity/Paiaro Herbicide.mxd (04.10.11) mg 



Pacific 

Ocean 




Non-Instream Herbicide Application: 2002 - 2012 (only) 

Non-Instream Herbicide Application: 2002 - 2012 and 2012-2022 (both) 
Non-Instream Herbicide Application: 2012 - 2022 (new) 

- County Boundary - Upper Elevation Boundary of SMP 

Streams - Watershed Boundaries 

—($)— Major Roads 

Notes: Non-instream application occurs above the bankfull channel elevation. Project area maps 
provide a general description of work type and area for the 2012-2022 SMP Update and are not 
intended to represent the exact locations of future work. 


0 1.5 3 6 

Source: Santa Clara Valley Water District, 2010; ESRI Roads, 2010 


Horizon 

WATER *p<t ENVlRONUfMT 


Figure 2-38: Pajaro Watershed Maintenance Activity 
Non-Instream Herbicide Application 
















This page intentionally left blank. 



s:/2010/Horizon/SCVWD/GIS/Layouts/Canals.mxd (02.02.11) mg 



SAN 

JOAQUIN 

COUNTY 


ALAMEDA 

COUNTY 


SAN L 
MATEO 
COUNT* 


Milpitas 


SANTA 

CLARA 

COUNTY 


STANISLAUS 

COUNTY 


San V 
Jose 


- ^ , —-—. Page 

X lu \ Distribution 

Sf co ■ System 

A ^ Upper 

■ ‘Vasona ' 
Canal^v 

T A 

Valley 

''''•Watershed vVi 


6phed v 

Coyote ^ ^ 

Alamitos Canal 


Kirk 

'^^Distribution 
£ System 


Coyote 

■Canal 

Extensions, 


^Coyote’ 

Canal 


'Almaden 
pw Calero, 
^ Canal, 


SANTA 

CRUZ 

COUNTY 


Monterey 

Bay 


SAN 

BENITO 

COUNTY 


MONTEREY 

COUNTY 


San 

Francisco' 
- Bay 


Pacific 


Detail Area 





Canals 

County Boundary 
Major Hydrologic Features 
Major Roads 

Upper Elevation Boundary of SMP 


A 

N 

1 inch = 7.75 miles 


Ocean 


Watershed Boundaries 



Miles 


5 10 


Horizon 

* W *•< IVf •QHKiyr 


Figure 2-39. Canals 

























This page intentionally left blank. 




CD 

_Q 

O 

O 

O 

I 





CD 

s_ 

_Q 

CD 


I 

O 

CD 

Q 




Figure 2-41 
Annual SMP Work Sequence 

























Chapter 3 

Environmental Setting and Impact Analysis 


3.0 Introduction 

3.0.1 Introduction to the Environmental Setting and Impact Analysis 

Chapter 3, Environmental Setting and Impact Analysis of this DSEIR contains thirteen 
sections that describe the environmental resources and potential environmental impacts of 
the Proposed Project. Each one (Sections 3.1 through 3.13] contains the following 
information about its resource topic: 

■ a description of the environmental setting as well as background information about 
the resource topic, to help the reader understand the resources that could be 
affected by the Proposed Project; 

■ any regulations that may govern activities affecting the resource; 

■ a discussion of the criteria and thresholds used in determining the significance of 
the Proposed Project's environmental impacts; 

■ a discussion of the impacts of the Proposed Project on the resource, including the 
significance of each impact; and 

■ mitigation measures, including best management practices that would allow SCVWD 
to avoid, minimize, or compensate for any significant impacts. 

This EIR has been prepared as a Subsequent EIR. Since the certification of the SMP Final EIR 
in 2002, substantial changes have been proposed to the SMP, and new information of 
substantial importance has developed. The project changes, changed circumstances, and 
new information have the potential to involve new or worsened significant environmental 
effects not evaluated in the 2002 SMP EIR. Under these circumstances, CEQA (Public 
Resources Code Sec. 21666] and the CEQA Guidelines (Sec. 15162] require that a 
Subsequent EIR be prepared. 

Normally, when a Subsequent EIR is prepared, the environmental setting and baseline 
include the environmental impacts disclosed in the original EIR, and the Subsequent EIR 
discloses any additional impacts caused by project changes, changes in circumstances, or 
new information. Due to the extensive nature of the proposed changes to the existing SMP, 
it would have been technically very difficult to segregate the environmental effects of the 
proposed changes from the effects of the existing SMP, and to use a baseline of post-project 
environmental conditions through 2020 as disclosed in the 2002 SMP EIR. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.0-1 


December 2011 
Project 10.005 



3.0 Environmental Setting and Impact Analysis 


Therefore, the project description for the SMP Update is comprehensive, and includes 
activities under both the existing SMP and the proposed changes to the SMP. This SEIR uses 
existing conditions at the time of the Notice of Preparation as the environmental setting and 
baseline, and analyzes the 2012 - 2020 impacts of the comprehensive SMP Update against 
this baseline. This conservative approach to the Subsequent EIR baseline and impact 
analysis scope represents an exception to established District CEQA practice due to the 
unique nature of the proposed SMP changes. It will not necessarily be employed in future 
District Subsequent EIRs for other projects in the absence of similar unique circumstances. 

3.0.2 Sections Eliminated from Further Analysis 

Four CEQA checklist resource areas have been eliminated from further analysis. Based on 
the nature and scope of Proposed Project activities, either no potential exists for significant 
impacts to these resources or they have been dismissed because the impacts associated 
with the topic have been addressed in other sections. A brief summary of the excluded 
resources is presented next. Also of note, two resource topics from the checklist are 
combined; public services and utilities, and service systems are discussed in Section 3.10, 
Public Services and Utilities. 

Agricultural Resources 

The Project Area covers a large portion of Santa Clara County (Figure 2-1], which contains a 
significant amount of land in agricultural uses. However, no activities under the Proposed 
Project would have an effect on these lands. Farmland and agricultural uses may be located 
near SMP Update maintenance sites; however, all Proposed Project activities would take 
place within flood protection channels and canals maintained by the SCVWD. These 
facilities do not contain lands designated or used for agriculture. In addition, these activities 
would be limited to maintenance and repair, and would not result in more intensive land 
development. No Prime Farmland, Unique Farmland, or Farmland of Statewide Importance, 
or lands under a Williamson Act contract would be converted under Proposed Project 
activities. 

Geology and Soils 

The Proposed Project would involve limited construction of permanent structures (e.g., 
culvert replacement], which could be subject to earthquake-related hazards, unstable soils, 
expansive soils, or other geotechnical hazards. However, these facilities would be designed 
to meet appropriate professional standards to avoid such hazards and, as a result, no 
significant impacts are anticipated to result. The Proposed Project does include some 
activities that have a potential to lead to topsoil erosion; erosion and siltation are addressed 
in Section 3.13, Water Quality. Furthermore, the Proposed Project would not involve the 
construction of any housing units requiring the use of septic tanks or other wastewater 
disposal systems. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.0-2 


December 2011 
Project 10.005 



3.0 Environmental Setting and Impact Analysis 


Mineral Resources 

Proposed Project activities would have no impact on the availability or use of a known, 
valuable mineral resource in Santa Clara County. 

The Project Area includes a variety of streams, channels, and canals, used for flood 
protection. No aggregate mining facilities are currently operating within SCVWD- 
maintained facilities. Although mines or mineral resource areas may be located near 
Proposed Project work sites, none of these activities could directly affect those mineral 
production sites. 

Sediment excavated under the SMP may be reused, with potential to offset demand for 
mineral resources such as aggregate. However, the total volume of dredged material created 
under the Proposed Project in any given year would be small (averaging approximately 
46,500 cubic yards], and the amount available for reuse would be a fraction of this amount. 
This would not represent an appreciable fraction of the total aggregate resources used 
annually in the County. 

Population and Housing 

The Proposed Project does not involve the construction of permanent structures such as 
housing and employment centers, nor would it involve the creation of any new 
infrastructure. It only involves maintaining existing infrastructure. Thus, the Proposed 
Project would not induce growth either directly or indirectly. The Proposed Project would 
not displace any existing housing units or persons, as no habitable structures exist within 
the stream reaches where maintenance would occur. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.0-3 


December 2011 
Project 10.005 




Chapter 3.1 


Aesthetics 





3.1 Aesthetics 


3.1.1 Introduction 

This section presents the regulatory setting, environmental setting, and potential impacts of 
the Proposed Project as related to aesthetics. 

Visual Character and Viewshed 

Both natural and artificial landscape features make up the character of a view. The area of 
the landscape that is visible from a particular location (e.g., an overlook] or series of points 
(e.g., a road or trail] is defined as a viewshed. Visual character is influenced by geologic, 
hydrologic, botanical, wildlife, recreational, and urban features. Urban features include 
aspects of landscape settlement and development, such as roads, utilities, structures, 
earthworks, and the results of other human activities. The perception of visual character 
can vary significantly among viewers, depending on their level of sensitivity and interest. 
Among sensitive viewers, perception can vary seasonally and even hourly as weather, light, 
shadow, and the elements that compose the viewshed change. Form, line, color, and texture 
are the basic components used to describe visual character and quality for most visual 
assessments (USFS 1974, FHWA 1983], Under this system, the appearance of the viewshed 
is described in terms of the dominance of each of these components. 

Visual Quality 

Visual quality is evaluated in this section using the well-established approach to visual 
analysis adopted by the Federal Highway Administration (Jones, et al. 1975, FHWA 1983], 
employing the concepts of vividness, intactness, and unity, as defined below: 

■ Vividness is the visual power or memorability of landscape components as they 
combine in striking or distinctive visual patterns. 

■ Intactness is the visual integrity of the natural and human-built landscape and its 
freedom from encroaching elements; this factor can be present in well-kept urban 
and rural landscapes, as well as in natural settings. 

■ Unity is the visual coherence and compositional harmony of the landscape 
considered as a whole; it frequently attests to the careful design of individual 
components in the artificial landscape. 

Visual quality is evaluated based on the relative degree of vividness, intactness, and unity, 
as modified by its visual sensitivity, discussed next. High-quality views are highly vivid, 
relatively intact, and exhibit a high degree of visual unity. Low-quality views lack vividness, 
are not visually intact, and possess a low degree of visual unity. 

Visual Sensitivity and Viewer Response 

The measure of the quality of a view must be tempered by the overall sensitivity of the 
viewer. Viewer sensitivity is based on the visibility of resources in the viewshed, the 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-1 


December 2011 
Project 10.005 



3.1 Aesthetics 


proximity of viewers to the visual resource, the elevation of viewers relative to the visual 
resource, the frequency and duration of viewing, the number of viewers, and the type and 
expectations of individuals and viewer groups. 

The criteria for identifying the importance of views are related in part to the position of the 
viewer relative to the resource. To identify the importance of views of a resource, a 
viewshed may be divided into distance zones of foreground, middleground, and 
background. Generally, the closer a resource is to the viewer, the more dominant it is and 
the greater is its importance to the viewer. Although distance zones in viewsheds may vary 
between different geographic regions or types of terrain, a commonly used set of criteria 
identifies the foreground zone as 0.25-0.5 mile from the viewer, the middleground zone as 
extending from the foreground zone to approximately 3-5 miles from the viewer, and the 
background zone as extending from the middleground zone to infinity (USFS 1974], 

Judgments of visual quality and viewer response must be made based in a regional frame of 
reference (USSCS 1978], The same type of visual resource in different geographic areas 
could have a different degree of visual quality and sensitivity in each setting. For example, a 
small hill may be a significant visual element in a flat landscape but have very little 
significance in mountainous terrain. 

Generally, visual sensitivity is higher for views seen by people who are driving for pleasure; 
people engaging in recreational activities such as hiking, biking, or camping; and 
homeowners. Sensitivity tends to be lower for views seen by people driving to and from 
work or as part of their work (USFS 1974, USSCS 1978, FHWA 1983], Commuters and 
nonrecreational travelers have generally fleeting views and tend to focus on commute 
traffic, not on surrounding scenery; therefore, they are generally considered to have low 
visual sensitivity. Residential viewers typically have extended viewing periods and are 
concerned about changes in the views from their homes; therefore, they generally are 
considered to have moderate to high visual sensitivity. Viewers using recreation trails and 
areas, scenic highways, and scenic overlooks are usually assessed as having high visual 
sensitivity. 

3.1.2 Regulatory Setting 

Federal Plans, Policies, Regulations, and Laws 

No federal plans, policies, regulations, or laws related to aesthetics are applicable to the 
Proposed Project. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-2 


December 2011 
Project 10.005 



3.1 Aesthetics 


State Plans, Policies, Regulations, and Laws 

California Department of Transportation State Scenic Highway System 

Maintenance of channels and canals under the Proposed Project that are near designated 
State Scenic Highways could affect views from these highways. The State Scenic Highways 
relevant to the Proposed Project are described in Section 3.1.3, Environmental Setting. The 
California Scenic Highway Program was established in 1963, under Sections 260 through 
263 of the Streets and Highways Code. The Scenic Highway Program includes a list of 
highways that are either designated or eligible for designation as scenic highways (Caltrans 
2010], For a State Scenic Highway-eligible roadway to be officially designated, the local 
jurisdiction in which it resides must adopt a scenic corridor protection program and apply 
to the California Department of Transportation (Caltrans] for scenic highway approval, 
identifying and defining the scenic corridor of the highway. Once approved by Caltrans, the 
local jurisdiction receives notification that the highway has been designated a State Scenic 
Highway. The local jurisdiction must then adopt ordinances to preserve the scenic quality of 
the corridor or document the regulations that already exist in various portions of local 
codes, creating the scenic corridor protection program. A scenic corridor is defined as land 
that is visible from the highway right of way and comprised primarily of scenic and natural 
features. Scenic corridor boundaries are determined by topography, vegetation, viewing 
distance, and/or jurisdictional lines. Officially designated State Scenic Highways are marked 
with a California poppy, the logo for the California Scenic Highway Program. 

Regional and Local Plans, Policies, Regulations, and Ordinances 

Applicable regional and local plans, policies, regulations, or ordinances related to aesthetics 
are presented in Appendix D. 

3.1.3 Environmental Setting 

Regional Character 

Santa Clara County's major topographic features include the Baylands, the Santa Clara 
Valley, the Diablo Range to the east, and the Santa Cruz Mountains to the west. The Baylands 
are in the northwestern part of the county, adjacent to the waters of the southern San 
Francisco Bay, and consist mostly of salt evaporation ponds and areas of salt marsh and 
wetlands. The Santa Clara Valley is oriented in a northwest-southeast direction and is 
surrounded by rolling hills. The entire eastern half of the county is encompassed by the 
Diablo Range, which is covered by grasslands, brush and oak savannah. The lands of the 
Diablo Range typically have much less natural vegetative cover and far fewer stands of trees 
than the Santa Cruz Mountains (County of Santa Clara 2005], On the western side of the 
valley, the lower elevations of the Santa Cruz Mountains are characterized by rolling 
grasslands and oak-studded foothills. In the higher elevations of the Santa Cruz Mountains, 
the landscape transitions to mixed hardwoods and dense evergreen forests. (County of 
Santa Clara 1994] 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-3 


December 2011 
Project 10.005 



3.1 Aesthetics 


Urbanization in the county has primarily occurred in the northern part of Santa Clara Valley. 
The majority of the county's residents (approximately 90 percent] and the county's cities 
(13 out of 15] are located in the North Valley. The remaining two cities, Gilroy and Morgan 
Hill, are located in the South Valley. Unlike the North Valley, the South Valley is 
predominantly rural, with the exception of Gilroy, Morgan Hill, and the small 
unincorporated community of San Martin. Low-density residential developments 
predominate in both valley areas and the surrounding foothills. (County of Santa Clara 
1994] 

View sheds 

Views from the Santa Clara Valley floor are primarily of the foothills, ridges, and/or 
summits of the Santa Cruz Mountains and the Diablo Range. The topography and ridgelines 
within the county are highly variable. Along the eastern Diablo Range, prominent ridges run 
generally parallel to the Santa Clara Valley floor, from northwest to southeast. However, the 
Santa Cruz Mountains have a dominant ridge (the Summit Road area] that divides Santa 
Clara County from San Mateo and Santa Cruz Counties and intervening lower ridge areas. 
The lower ridge areas have other ridges or hillsides as their backdrop and can be oriented 
in many directions. This topography results in the Diablo Range being more visible from the 
valley than the Santa Cruz Mountains to the east. (County of Santa Clara 2005, 2006] 

Public open spaces in the Project Area with scenic vistas include Almaden Quicksilver, 
Calero, Coyote Lake-Harvey Bear Ranch, Ed Levin, Mt. Madonna, Santa Teresa and Upper 
Stevens Creek county parks, and numerous smaller regional and local parks (County of 
Santa Clara 2010], 

Scenic Highways and Corridors 

One stretch of highway in the Project Area, a portion of the 10.9-mile stretch of State Route 
(SR] 9 from the Santa Cruz county line to the Los Gatos city limits, has been officially 
designated by Caltrans as a State Scenic Highway (Caltrans 2010], In the Project Area, this 
State Scenic Highway follows upper Saratoga Creek and crosses Wildcat Creek within the 
West Valley Watershed (Figure 2-3], 

Six stretches of highway, either completely or partially within Santa Clara County, have 
been identified as eligible for designation as State Scenic Highways: SR 9 from SR 35 to 
SR 17 near Los Gatos; SR 17 from SR 1 near Santa Cruz to SR 9 near Los Gatos; SR 35 from 
SR 17 to SR 92, Interstate 280, and SR 1 in San Francisco; SR 152 from SR 156 near San 
Felipe to Interstate 5; SR 156 from SR 1 near Castroville to SR 152 northeast of Hollister; 
and Interstate 280 from SR 17 to Interstate 80 near First Street in San Francisco. 

Santa Clara County also has designated an extensive network of roadways as Scenic 
Highways. This network includes unincorporated areas of the county, offering a diversity of 
viewsheds to travelers. State Highways 9, 17, 35, 101, 152, 156, 280, 680, and numerous 
local roads are identified as existing or proposed Scenic Highways (County of Santa Clara 
1994,2008], 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-4 


December 2011 
Project 10.005 



3.1 Aesthetics 


In addition, some of the incorporated cities within Santa Clara County have identified scenic 
corridors and aesthetic resources. Overall, these are located around waterways and 
roadways that are identified by the County with views of the hillsides surrounding each city. 
Consistency of the Proposed Project with local policies to protect scenic corridors and 
aesthetic resources is discussed in Appendix D. 

Where scenic highways and corridors intersect with SCVWD-maintained facilities, views 
from these highways and corridors could be affected by Proposed Project maintenance 
activities. In the Project Area, maintenance activities at tributary drainages to the Lexington 
Reservoir may be visible from SR 17 within the Guadalupe Watershed (Figure 2-4], 
Additionally, maintenance activities in upper Pacheco Creek from San Felipe to Pacheco 
Lake may be visible from SR 156 within the Pajaro Watershed (Figure 2-6], 

Recreational Trails 

The access roads that parallel most SMP-maintained channels and canals also provide 
creekside recreational (formal and informal] access. Some of these access roads are 
formalized as recreational trails, with signage and other amenities, such as benches. These 
trails provide an important recreational resource, particularly in the urban environment of 
San Jose. Creek-side trails typically are composed of consolidated earth or gravel, or are 
fully paved. Most of the Project Area channels and canals have some type of maintenance 
access road that also can serve as an informal creek-side trail or pathway. Although many of 
the access roads in the Project Area are not publicly accessible, many miles of 
roadways/trails are. Where accessible, these trails are used for a variety of recreational 
activities including walking, jogging, biking, dog-walking, and bird watching, and they 
provide aesthetic value for recreational users. See Section 3.11, Recreation for further 
discussion of recreational activities on creekside trails in the Project Area. 

Aesthetic Quality at SMP Facilities 

The creeks in Santa Clara County drain runoff from the Santa Cruz Mountains and the Diablo 
Range to the valley floor and, eventually, to either Monterey Bay or San Francisco Bay. Many 
of these water bodies flow through or near the county's urban areas, offering potential 
opportunities for views of creeks, stream channels, and canals, depending on the 
surrounding bank vegetation, access to or along the channels or canals, and other view- 
restricting factors. As described in Chapter 2, Project Description, the majority of the stream 
channels in the Project Area are "earthen,” including both modified and unmodified 
channels. Other stream channels and canals in the Project Area consist of mixed or concrete 
channels. 

The aesthetic quality of SCVWD-maintained facilities varies from reaches nearly devoid of 
vegetation to reaches supporting a full riparian canopy (see photos in Figure 3.1-1], Many of 
the creek reaches that would be maintained under the Proposed Project are located along 
public roadways or trails. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-5 


December 2011 
Project 10.005 



3.1 Aesthetics 


This page intentionally left blank. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-6 


December 2011 
Project 10.005 




K V 

bBL t f 

^•* -- 



Niini JHH 

• 'W&u: r • ts w’VV WL 

f* rjcWV. -vaJr. 


SMP channels support riparian habitat and recreationa 
(Los Gatos Creek) 

paths 

Steep banks and instream vegetation (San Francisquito Creek) 


■l. ’ 5 1 



| 

- ~=' 

. *• 

r> jjwyk*'' ■ t 

bw>#iSf 

. -.'v> ! 

Kv; 'V* :■?*&..- 

MBM' . .. . V - 


Concrete-1 

ned channel (Guadalupe River) 

Modified channel nearly devoid of riparian vegetation (Sierra 

Creek) 


>• 



1# 4 

••’'''- ■ :V .■■■ ■ ^ y 1 


Algae growth in stagnant summer low flow conditions (Pacheco 
Creek) 

Tidal areas near San Francisco Bay (lower Coyote Creek 



fck ._ J? : . 



iffajlr^rn J 29... - 


View to riparian vegetation along Coyote Creek (left) from 
recreational path on top of a levee 

SCVWD channels include engineered structures and crossings 


Horizon 

^ ^ WAI bR and ENVIRONMENT 


Figure 3.1-1 

Representative Photos of SMP Channels 



































3.1 Aesthetics 


This page intentionally left blank. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-8 


December 2011 
Project 10.005 



3.1 Aesthetics 


In urbanized areas, such as within the City of San Jose, efforts would continue to be made to 
use creeks as the center focus of development, thus elevating the scenic value provided by 
creeks and their riparian vegetation. The City of San Jose, as described above, has strived to 
protect the aesthetic value of Guadalupe River and other local creeks by maintaining public 
multi-use trails along their banks. The public value of creeks in the Project Area is 
evidenced by the policies included in the local general plans, as listed in Appendix D. 

Depending on their location, creeks and canals maintained under the SMP Update would be 
viewed by recreationalists, such as bicyclists, joggers, and horseback riders, as well as 
residents, people working in proximity to the creeks, other pedestrians, and motorists. 
Public access adjacent to the channels and canals maintained by the SMP Update may be 
provided by trails that would be located along the top of banks and at creek crossings. 

SCVWD has been conducting maintenance activities similar to those proposed for the SMP 
Update for a number of years. Although the Proposed Project includes some new 
maintenance activities and the extension of some activities to portions of some streams not 
historically subject to those activities, overall, the baseline for analysis of impacts is a 
stream system that has already been altered by maintenance activities on an ongoing basis. 

Viewer Groups and Viewer Responses 

Viewer groups in the vicinity of the Project Area and their sensitivity to visual changes in 
the area are characterized below. Viewer groups who have visual access to SCVWD- 
maintained facilities were divided into the categories of recreational users, residents, 
workers, and motorists. 

Recreational Users 

Recreational use in the Project Area includes a variety of activities, such as walking, jogging, 
biking, dog-walking, and bird watching. Many hiking trails within county parks, such as 
Almaden Quicksilver, Sanborn-Skyline, Rancho San Antonio, Joseph D. Grant, Calero, 
Mt. Madonna, Coyote Lake-Harvey Bear Ranch, Ed Levin, and Anderson Lake, provide views 
of the Santa Clara Valley, the Bay, and/or the surrounding mountain ranges (County of 
Santa Clara 1995, 2010], Viewer sensitivity is moderately high among recreational users 
because they highly value the natural environment, appreciate the visual experience, and 
are sensitive to changes in views. 

Residents 

Residents are individuals whose homes are in proximity to SCVWD-maintained facilities in 
the Project Area. Similar to recreational users, viewer sensitivity is moderately high among 
residents because they highly value their local visual resources, appreciate the visual 
experience, and are fairly sensitive to changes in views. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-9 


December 2011 
Project 10.005 



3.1 Aesthetics 


Workers 

Workers are those whose place of employment is near SCVWD-maintained facilities in the 
Project Area, or who may come into contact with such facilities as part of their work 
activities (e.g., delivery persons]. Viewer sensitivity is moderate among workers because 
they generally are not highly focused on the visual resources surrounding their workplace 
and are less sensitive to changes in views. 

Motorists 

Motorists use roadways at varying speeds; normal highway and roadway speeds differ 
based on the design speed of the roadway, traffic volumes, traveler's familiarity with the 
route, and roadway conditions (e.g., presence/absence of rain]. Single views typically are of 
short duration, except on straighter stretches where views last slightly longer. Motorists 
who frequently travel the same routes generally possess low to moderate visual sensitivity 
to their surroundings. The passing landscape becomes familiar to them, and their attention 
typically is not focused on passing views but on the roadway, roadway signs, and 
surrounding traffic. Motorists who travel local routes for sight-seeing purposes generally 
possess a higher visual sensitivity to their surroundings because they are likely to respond 
to the natural environment with higher regard and as a holistic visual experience. 

Viewer sensitivity is expected to be moderately low for most roadway travelers anticipated 
in the Project Area. The passing viewshed would become familiar to frequent viewers; 
furthermore, at standard roadway speeds, views would be of short duration and roadway 
users would be only fleetingly aware of surrounding traffic, road signs, their immediate 
surroundings within the automobile, and other visual features. 

3.1.4 Impact Analysis 

Methodology 

This section describes the methods used to determine the Proposed Project's impacts and 
lists the thresholds used to conclude whether an impact would be significant. 

The methodology used to assess possible visual resource impacts that could be caused by 
the Proposed Project includes the following: 

1. Objectively identify visual features (visual resources] in the Project Area. 

2. Assess the character and quality of those resources relative to the overall regional 
visual character. 

3. Identify the importance to people or their sensitivity regarding views of visual 
resources in the viewshed. 

4. Characterize the nature of changes to visual resources resulting from implementing 
the Proposed Project. 

5. Assess the significance of these changes in light of items 1-4. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-10 


December 2011 
Project 10.005 



3.1 Aesthetics 


By establishing the baseline (existing] conditions, changes resulting from activities under 
the Proposed Project or other changes to the viewshed can be objectively evaluated for 
their degree of impact. The degree of impact depends both on the magnitude of change in 
the visual resource (i.e., visual character and quality] and on viewers' responses to and 
concern for those changes. This general process is similar for all established federal 
procedures of visual assessment (Smardon et al. 1986] and represents a suitable 
methodology of visual assessment for the Proposed Project. 

Implementation of the Proposed Project was evaluated based on the potential to impact the 
following viewer groups, which are most likely to be affected by Proposed Project activities: 
recreational users (pedestrians and cyclists], residents, workers, and motorists (drivers and 
passengers in cars or motorcycles]. 

Criteria for Determining Significance 

For the purposes of this analysis, the Proposed Project would result in a significant impact 
on aesthetics if it would: 

A. have a substantial adverse effect on a scenic vista or designated scenic highway; 

B. substantially damage publicly visible scenic resources, including, but not limited to, 
trees, rock outcroppings, and historic buildings; 

C. substantially degrade the existing visual character or quality of the site and its 
surroundings; or 

D. create a new source of substantial light or glare that would adversely affect day or 
nighttime views in the area. 

Environmental Impacts 

Impact AES-1: Alteration to a Scenic Vista 
(Significance Criteria A, B; Less than Significant) 

Scenic viewpoints within the Project Area are generally located at relatively high elevations 
along ridgelines within public open space areas and are typically viewed by recreational 
hikers and bicyclists, and motorists. The Proposed Project maintenance activities would 
occur within creek corridors or in canals at lower elevations, mostly on the valley floor. No 
maintenance activities would be conducted above the 1,000-foot elevation contour, where 
the majority of scenic vista points in the county are located. 

The distance from publicly accessible ridgeline trails and scenic vistas to creeks and canals 
in the valley is generally 2 to 5 miles. Because of the extent of the viewing distance and 
considering that many of the maintenance sites would be obscured from view by vegetation, 
it is unlikely that Proposed Project maintenance activities would be highly noticeable from 
scenic vistas. Maintenance vehicles and maintenance workers would be indistinguishable 
from other vehicles at this distance. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-11 


December 2011 
Project 10.005 



3.1 Aesthetics 


Sediment Removal 

Removal of sediment from SCVWD channels and facilities would result in temporary 
presence of vehicles, machinery, and personnel at sites during the maintenance period. 
Once work is completed, the channel itself would be visibly cleared of sediment. However, 
such changes would not be noticeable from scenic vista points for the reasons described 
above. 

Vegetation Maintenance 

Proposed vegetation maintenance activities, such as tree removal and limbing, could 
potentially alter the character of riparian corridors within the Project Area. In general, this 
alteration would not be highly noticeable when viewed from a scenic viewpoint. 

Management of Animal Conflicts/Minor Maintenance/Bank Stabilization 

As described in the SMP Manual (Appendix A], management of animal conflicts would 
involve small-scale activities (e.g., use of traps, filling of burrows], which would not be 
visible from a scenic vista. Similarly, minor maintenance activities (e.g., graffiti removal, 
small-scale sediment removal] would have limited potential to impact scenic vistas. Bank 
stabilization projects would result in sections of visibly altered banks with new materials 
used to conduct repairs. Given the few number of bank stabilization projects that are likely 
to occur per year (averaging approximately 1 mile in total], adverse effects on scenic vistas 
would be minimal. 

Canal Maintenance 

Because routine canal maintenance activities would include all general work activities, 
effects would be the same as described above for other routine maintenance work. 

Applicable Best Management Practices 

The following BMPs implemented as part of the SMP Update would help prevent 
maintenance activities from substantially degrading a scenic vista. Descriptions of each BMP 
are provided in Chapter 2, Project Description. 

BMP GEN-19: Work Site Housekeeping 

BMP REVEG-1: Seeding 

BMP REVEG-2: Planting Material 

Conclusion 

Given the relatively minor effect that Proposed Project activities would have on views from 
scenic vistas, this impact would be less than significant and would not require mitigation. 

Mitigation Measures: No mitigation is required. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-12 


December 2011 
Project 10.005 



3.1 Aesthetics 


Impact AES-2: Alteration to Scenic Resources Viewed from a State or County- 
designated Scenic Highway (Significance Criterion A; Less than Significant) 

As described above in Section 3.1.3, Environmental Setting, one stretch of highway within 
the Project Area is officially designated by Caltrans as a State Scenic Highway, and Santa 
Clara County has designated a number of roads within the Project Area as scenic highways. 
These scenic highways generally are located along waterways and provide views of the hills 
surrounding the county. 

Maintenance activities in areas where creeks or canals are close to scenic highways could 
temporarily (but in some cases, repeatedly] disrupt views. However, scenic highways in the 
Project Area are utilized by motorists traveling at highway speeds. Motorists traveling on 
designated scenic highways generally would have only fleeting views of maintenance 
activities and post-maintenance alterations to stream channels or canals. 

Vegetation Maintenance 

The pruning and removal (physically or using herbicide treatment] of vegetation could 
disrupt views along scenic highways or corridors. Although vegetation management would 
occur in multiple locations at any given time, the majority of vegetation maintenance 
activities would be done infrequently at any particular location, allowing for vegetation to 
grow back after vegetation maintenance activities had been conducted. Thus for the 
majority of vegetation maintenance activities, impacts would be less than significant. 

In some areas, herbicide treatment would be done repeatedly to maintain the location in a 
permanently denuded state. Though limited, this type of treatment would alter scenic 
resources of the area over the long term, and may be located within the viewpoint of a 
scenic highway or corridor. However, maintaining areas in this state could have a beneficial 
effect by promoting consistency (as opposed to alternating views of cleared areas and 
regrowth stages] and minimizing views of overgrowth. Overall, impacts from repeated 
herbicide treatment would be expected to have a slightly greater potential for impacts. 

Other Maintenance Activities 

The remainder of maintenance activities (sediment removal, bank stabilization, 
management of animal conflicts, canal maintenance, and minor maintenance] would occur 
in multiple locations, but would generally be done infrequently at any one location and 
would have only temporary impacts. Even in the case of repeat activities (e.g., rodent 
control], the appearance of these maintenance activities and post-maintenance alterations 
would not leave a lasting impression on the overall view from the window of a car traveling 
at highway speeds. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-13 


December 2011 
Project 10.005 



3.1 Aesthetics 


Applicable Best Management Practices 

The following BMPs would be implemented as part of the SMP Update to prevent 
maintenance activities from substantially degrading scenic resources along a waterway or 
altering views of surrounding hillsides. Descriptions of each BMP are provided in Chapter 2, 
Project Description. 

BMP GEN-19: Work Site Housekeeping 

BMP REVEG-1: Seeding 

BMP REVEG-2: Planting Material 

Conclusion 

The impact on State or County-designated scenic highways resulting from the Proposed 
Project would be less than significant and would not require mitigation. 

Mitigation Measures: No mitigation is required. 

Impact AES-3: Temporary Alteration of Visual Character or Quality from Maintenance 
Activities (Significance Criteria B, C; Significant and Unavoidable) 

Many miles of creekside recreational trails currently exist or are planned within the Project 
Area. These creekside trails are utilized by recreational users and commuters, and are 
located in residential, commercial, and open space areas. 

Short-term maintenance activities including vegetation management, sediment removal, 
and bank protection could result in a temporary degradation of visual quality. These 
impacts are described below. 

Vegetation Management 

During vegetation management activities, a temporary visual impact would occur from the 
presence of maintenance crews and equipment near channels. Vegetation management 
could degrade the visual character of creeks and canals if it were to remove major stands of 
large vegetation. Invasive plant removal activities may alter a densely vegetated area to a 
partially vegetated or bare area until newly planted vegetation grow in. Herbicide activities 
also could alter the visual character of a site as targeted vegetation was destroyed. In 
addition, impacts from tree removal in areas where existing trees were sparse and where 
replanting was infeasible could be substantial. 

Sediment Removal and Bank Stabilization 

For sediment removal and bank stabilization activities, a temporary visual impact also 
would occur from maintenance crews and equipment near and in channels. Both sediment 
removal and bank stabilization projects could result in areas that would be temporarily de- 
vegetated, which on some creeks in the system would be different from areas surrounding 
the site, although bank stabilization sites would include a revegetation component, where 
feasible (see Appendix C, which describes the revegetation approach for bank stabilization 
activities]. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-14 


December 2011 
Project 10.005 



3.1 Aesthetics 


Viewer response to altered canal, channel, and riparian corridors after maintenance 
activities may vary. Commuters on creekside trails who passed by the site on a daily basis 
could react to the changed conditions. However, such changed conditions would be 
temporary (because vegetation would grow back over time] and would occur at isolated 
locations. Likewise, sediment removal projects that would remove silt, vegetation and other 
blockages may allow the creek to function more naturally, resulting in an aesthetic benefit. 

Management of Animal Conflicts 

Other than the temporary presence of maintenance personnel and vehicles, activities 
proposed for animal conflict management would not involve actions which could result in 
the temporary alteration of visual character or quality. Bait traps, if left on-site, would be 
hidden or otherwise made inconspicuous to prevent vandalism and theft. 

Minor Maintenance 

Minor maintenance activities generally would be small scale (e.g., small amounts of 
sediment removal, removal of debris], and would have limited potential to impact visual 
quality. However, the installation/maintenance of landscape sites would result in a visual 
improvement at the time of installation. 

Canal Maintenance 

Because routine canal maintenance activities would include all general work activities, 
effects would be the same as described above for other routine maintenance work. 

Applicable Best Management Practices 

The following BMPs would be implemented as part of Proposed Project activities to address 
any temporary impacts on aesthetics during maintenance: 

BMP GEN-19: Work Site Housekeeping 

BMP REVEG-1: Seeding 

BMP REVEG-2: Planting Material 

Conclusion 

As discussed above, the majority of activities would have less-than-significant impacts on 
temporary alterations of visual character or quality and would not require mitigation. 
Implementation of Mitigation Measures BIO-1, BIO-2, and BIO-7 would further aid in 
reducing these impacts, where implementation of such mitigation would result in 
revegetation activities or tree planting being conducted on site. 

Depending on viewer sensitivity, tree removal in areas where revegetation was infeasible 
could result in a significant impact. No other feasible mitigation measures have been 
identified. Therefore, for the purposes of this DSEIR, temporary alterations on visual 
character or quality from tree removal without on-site tree replacement or replanting 
would be considered a significant and unavoidable impact. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-15 


December 2011 
Project 10.005 



3.1 Aesthetics 


Mitigation Measure BIO-1: Implement Compensatory Mitigation for Wetlands 
and Other Waters 

See Impact BIO-1 in Section 3.3, Biology Resources. 

Mitigation Measure BIO-2: Implement Compensatory Mitigation for Woody 
Riparian Vegetation 

See Impact BIO-1 in Section 3.3, Biology Resources. 

Mitigation Measure BIO-7: Tree Replacement 

See Impact BIO-7 in Section 3.3, Biology Resources. 

Impact AES-4: Permanent Alteration of Visual Character or Quality from Maintenance 
Activities (Significance Criterion C; Significant and Unavoidable) 

This impact discussion focuses on the long-term aesthetic effects of the Proposed Project. 
Overall, the long-term effect from maintenance activities would improve the visual 
character and quality of the Project Area. 

Sediment Removal and Bank Stabilization 

Removal of sediment from SCVWD channels and facilities would remove sediment, 
vegetation, and other blockages that would allow waterways to function more naturally, 
and thus resulting in an aesthetic benefit. Similarly, stabilization and repair of eroding 
banks would reduce sediment loss and in-channel build-up. Although the use of certain 
materials (i.e., rock, riprap] to repair banks could appear visually different, on-site 
revegetation (as described in Appendix C] would minimize long-term visual impacts and 
make them less than significant. 

Vegetation Management 

Overall, the removal of invasive plant species and revegetation with native species would 
improve the long-term aesthetic value of the riparian corridors. However, as discussed in 
Impact AES-3, proposed vegetation maintenance activities, such as tree removal, could 
potentially alter the character of riparian corridors in the Project Area. As discussed in 
Impact AES-3, this alteration would generally be less than significant, especially where 
replanting or revegetation would occur. As described in Section 3.3, Biological Resources, 
mitigation for larger-sized tree removals would be required, which would minimize 
permanent visual alterations. However, the impact on visual quality or character could be 
significant when tree removal was conducted in areas where existing trees were sparse and 
where replanting were infeasible. 

Management of Animal Conflicts 

Long-term effects from the management of animal conflicts could benefit the visual 
character or quality of treated areas. By discouraging damage caused by animal activity (i.e., 
burrowing], the integrity of SCVWD facilities would be preserved and visual damage would 
be minimized. Therefore, the permanent impacts from management of animal conflicts 
under the Proposed Project would be beneficial. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-16 


December 2011 
Project 10.005 



3.1 Aesthetics 


Minor Maintenance 

Minor maintenance activities, including installation/maintenance of landscape sites, debris 
removal, fence maintenance, and graffiti removal, would improve the visual quality and 
character of channels. Therefore, permanent effects on visual quality and character from 
these activities would be beneficial. 

Canal Maintenance 

Because routine canal maintenance activities would include all general work activities, 
effects would be the same as described above for other routine maintenance work. 

Applicable Best Management Practices 

SCVWD would implement the following BMPs as part of maintenance activities: 

BMP GEN-19: Work Site Housekeeping 
BMP SED-3: Restore Channel Features 
BMP REVEG-1: Seeding 
BMP REVEG-2: Planting Material 

The good housekeeping practices would be followed at all maintenance sites and the other 
BMPs would provide for revegetation activities to be implemented shortly after completing 
vegetation management, sediment removal, or bank stabilization activities that would 
remove vegetation. Furthermore, these BMPs would prevent maintenance activities from 
degrading scenic resources, and instead would improve the aesthetic character of the sites 
affected by maintenance activities. 

Conclusion 

As discussed above, most activities of Proposed Project would have a less-than-significant 
or beneficial impact on long-term aesthetic quality and would not require mitigation. 
Implementation of Mitigation Measures BIO-1, BIO-2 and BIO-7 would further aid in 
reducing these impacts, where implementation of such mitigation would result in 
revegetation activities or tree planting being conducted on site. 

However, in some instances permanent impacts on visual quality or character resulting 
from tree removal could be significant where replanting was not possible. No other feasible 
mitigation measures have been identified. Therefore, for the purposes of this DSEIR, 
permanent alterations on visual character or quality from tree removal in areas where 
replanting was infeasible would be considered a significant and unavoidable impact. 

Mitigation Measure BIO-1 Implement Compensatory Mitigation for Wetlands 
and Other Waters 

See Impact BIO-1 in Section 3.3, Biology Resources. 

Mitigation Measure BIO-2 Implement Compensatory Mitigation for Woody 
Riparian Vegetation 

See Impact BIO-1 in Section 3.3, Biology Resources. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-17 


December 2011 
Project 10.005 



3.1 Aesthetics 


Mitigation Measure BIO-7 Tree Replacement 

See Impact BIO-7 in Section 3.3, Biology Resources. 

Impact AES-5: Substantial Alteration to Day or Nighttime Views resulting from 
Additional Light or Glare (Significance Criterion D; No Impact) 

Proposed Project maintenance activities would be conducted during daylight hours only. No 
nighttime lighting would be utilized for maintenance activities. The Proposed Project would 
not involve construction of new facilities or modifications to existing facilities that would 
result in new reflective surfaces or installation of lighting. No impact would occur. 

Mitigation Measures: No mitigation is required. 

Impact AES-6: Impacts on Aesthetics Associated with Sediment Disposal/Reuse 
(Significance Criterion C; Less than Significant) 

Sediment removed from SCVWD-maintained channels and canals would be disposed or 
reused in various ways, depending on the quality of the excavated material, which may 
include but would not be limited to temporary stockpiling before reuse, off-site restoration 
or enhancement of ecologic function, or disposal at a landfill. 

Temporary Stockpiling 

When necessary, temporary stockpiling of the sediment would occur within staging areas 
associated with the work site or at other SCVWD-owned properties. The stockpiles could be 
located near residential and recreational viewers who may be sensitive to changes in the 
visual character of the site. However, impacts from stockpiling would be temporary and 
therefore less than significant. 

Off-Site Reuse by SCVWD 

Off-site reuse to support ecologic functions, such as tidal wetland habitat, would be likely to 
have similar impacts as described under Impact AES-3. Such activities would utilize 
sediment in a manner that would enhance the natural aesthetics of tidal wetland areas, and 
thus would be considered beneficial. 

Disposal at a Landfill 

If off-site reuse locations were unavailable or if the sediment was considered hazardous, it 
would be taken to a general waste or hazardous waste landfill. The amount of sediment 
generated from maintenance activities and disposed at a landfill would not exceed any 
landfill’s permitted capacities. Often, sediment materials are used at landfills as a 'cover' to 
cap accumulated garbage. This use of disposed sediment would therefore improve the 
aesthetic quality of the landfill. Impacts from disposal at a landfill would be considered 
beneficial. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-18 


December 2011 
Project 10.005 



3.1 Aesthetics 


Applicable Best Management Practices 

SCVWD would implement the following BMP as part of maintenance activities to screen any 
stockpiled sediment from public view, to the extent practical, for the duration that the 
sediment was stored: 

BMP GEN-21: Staging and Stockpiling of Materials 
Conclusion 

The aesthetic impacts of sediment reuse/disposal would be less-than-significant and would 
not require mitigation. 

Mitigation Measures: No mitigation is required. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.1-19 


December 2011 
Project 10.005 




Chapter 3.2 


Air Quality 





3.2 Air Quality 

3.2.1 Introduction 

This section presents the regulatory setting, environmental setting, and potential impacts of 
the Proposed Project related to air quality. 

Data sources used in the preparation of this section include state and federal regulations 
and reference materials from the Bay Area Air Quality Management District (BAAQMD], 

Specific to this section is the term "sensitive receptors,” meaning those who are particularly 
susceptible to the adverse effects of air pollution. These include children, the elderly, and 
people with illnesses. Examples include schools, nursing homes, hospitals, and residential 
areas. Air pollution can cause adverse health effects in humans, including aggravating 
asthma conditions and other respiratory problems (BAAQMD 2010], Sensitive receptors 
adjacent to stream reaches in the Project Area are numerous, and include people in 
residential areas, schools, elder care facilities, and hospitals. 

3.2.2 Regulatory Setting 

Federal Plans, Policies, Regulations, and Laws 

Clean Air Act 

The U.S. Environmental Protection Agency (USEPA] carries out the provisions of the Clean 
Air Act (CAA], originally passed in 1963 and amended six times, most recently in 1990. 
USEPA implements programs under the CAA that focus on reducing ambient air pollutant 
concentrations, reducing emissions of toxic pollutants, and phasing out production and use 
of chemicals that destroy stratospheric ozone. USEPA sets ambient air limits, the National 
Ambient Air Quality Standards (NAAQS] for six criteria pollutants: particulate matter, 
carbon monoxide, nitrogen oxides, sulfur oxides, ground-level ozone, and lead. The NAAQS 
are presented in Table 3.2-1. Primary standards are set for protection of human health and 
secondary standards are set for environmental protection. Areas which meet the primary 
standards are considered in "attainment" while areas with air quality not meeting the 
primary standards are in "non-attainment." 

Of the six criteria pollutants, particulate matter and ground-level ozone pose the most 
widespread threat to human health. Particle pollution poses the greatest threat to sensitive 
receptors including children, the elderly, and asthmatics, as it impairs lung function. Particle 
pollution includes very fine soot and dust. Sources of particulate matter include: ground- 
disturbing activities (such as construction grading and excavation]; motor vehicles; power 
generation activities; industrial operations; burning of fuels (such as wood, oil, and coal]; 
dust from unpaved roads; and crushing and grinding operations. Particle pollution can be 
carried by the wind and impair air quality far from its source. To reduce particle levels, 
USEPA regulates emissions from motor vehicles and point sources. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-1 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Table 3.2-1. State and Federal Ambient Air Quality Standards 


Contaminant 

Averaging Time 

State 

Standards 13 

Primary 

Federal 

Standards 2 ' 35 

Secondary 

Federal 

Standards 236 


1-hour 

0.09 ppm 

[180 pg/m 3 ] 

- 

- 

Ozone 

8-hour 

0.070 ppm 
[137 pg/m 3 , 
see note 4] 

0.075 ppm 
[147 pg/m 3 ] 

Same as primary 
standard 

Respirable Particulate 

24-hour 

50 pg/m 3 

150 pg/m 3 

Same as primary 
standard 

Matter [PM 10 ] 

Annual 

arithmetic mean 

20 pg/m 3 

- 

- 

Fine Particulate Matter 

24-hour 

- 

35 pg/m 3 

Same as primary 
standard 

(PM 2 . 5 ) 

Annual 

arithmetic mean 

12 pg/m 3 

15 pg/m 3 

Same as primary 
standard 


8-hour 

9.0 ppm 

9 ppm [10 mg/m 3 ] 

None 

Carbon Monoxide 

1-hour 

20 ppm 

35 ppm 
[40 mg/m 3 ] 

None 

Nitrogen dioxide 

Annual 

arithmetic mean 

0.030 ppm 
[57 pg/m 3 ] 

0.053 ppm 
[100 pg/m 3 ] 8 

Same as primary 
standard 

1-hour 

0.18 ppm 
[339 pg/m 3 ] 

0.100 ppm 
[188 pg/m 3 ] 8 



24-hour 

0.04 ppm 
[105 pg/m 3 ] 

0.14 ppm 
[365 pg/m 3 ] 

- 

Sulfur dioxide 

3-hour 

- 

- 

0.5 ppm 
[1,300 pg/m 3 ] 9 


1-hour 

0.25 ppm 
[655 pg/m 3 ] 

75 ppb 

[196 pg/m 3 ] 9 

- 


30-day average 

1.5 pg/m 3 

- 

- 

Lead 10 

Calendar quarter 

- 

1.5 pg/m 3 

Same as primary 
standard 


Rolling 3-month 
average 11 

- 

0.15 pg/m 3 

Same as primary 
standard 

Visibility reducing 
particles 

8-hour 

See note 7 

- 

- 

Sulfates 

24-hour 

25 pg/m 3 

- 

- 

Hydrogen Sulfide 

1-hour 

0.03 ppm 
[42 pg/m 3 ] 

- 

- 

Vinyl Chloride 10 

24-hour 

0.01 ppm 
[26 pg/m 3 ] 

- 

- 


ppm - parts per million by volume 

pg/m 3 - micrograms per cubic meter 

PMio - particulate matter less than 10 microns in diameter 

PM 2.5 - particulate matter less than 2.5 microns in diameter 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-2 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Table 3.2-1. State and Federal Ambient Air Quality Standards 

Notes: 

1. California standards for ozone, carbon monoxide (except Lake Tahoe), sulfur dioxide (1 and 24 hour), 
nitrogen dioxide, suspended particulate matter—PM 10, PM2.5, and visibility reducing particles, are 
values that are not to be exceeded. All others are not to be equaled or exceeded. California ambient air 
quality standards are listed in the Table of Standards in Section 70200 of Title 17 of the California Code of 
Regulations. 

2. National standards (other than ozone, particulate matter, and those based on annual averages or annual 
arithmetic mean) are not to be exceeded more than once a year. The ozone standard is attained when the 
fourth highest eight hour concentration in a year, averaged over three years, is equal to or less than the 
standard. For PM 10, the 24 hour standard is attained when the expected number of days per calendar 
year with a 24-hour average concentration above 150 pg/m 3 is equal to or less than one. For PM2.5, the 
24 hour standard is attained when 98 percent of the daily concentrations, averaged over three years, are 
equal to or less than the standard. Contact U.S. EPA for further clarification and current federal policies. 

3. Concentration expressed first in units in which it was promulgated. Equivalent units given in parentheses 
are based upon a reference temperature of 25°C and a reference pressure of 760 torr. Most 
measurements of air quality are to be corrected to a reference temperature of 25°C and a reference 
pressure of 760 torr; ppm in this table refers to ppm by volume, or micromoles of pollutant per mole of 
gas. 

4. Any equivalent procedure which can be shown to the satisfaction of the California Air Resources Board 
(CARB) to give equivalent results at or near the level of the air quality standard may be used. 

5. National Primary Standards: The levels of air quality necessary, with an adequate margin of safety to 
protect the public health. 

6 . National Secondary Standards: The levels of air quality necessary to protect the public welfare from any 
known or anticipated adverse effects of a pollutant. 

7. Extinction coefficient of 0.23 per kilometer—visibility of ten miles or more (0.07—30 miles or more for 
Lake Tahoe) due to particles when relative humidity is less than 70 percent. Method: Beta Attenuation 
and Transmittance through Filter Tape. 

8 . To attain this standard, the 3-year average of the 98th percentile of the daily maximum 1-hour average at 
each monitor within an area must not exceed 0.100 ppm (effective January 22, 2010). Note that the 
USEPA standards are in units of parts per billion (ppb). California standards are in units of parts per 
million (ppm). To directly compare the national standards to the California standards the units can be 
converted from ppb to ppm. In this case, the national standards of 53 ppb and 100 ppb are identical to 
0.053 ppm and 0.100 ppm, respectively. 

9. On June 2, 2010, USEPA established a new 1-hour S02 standard, effective August 23, 2010, which is based 
on the 3-year average of the annual 99th percentile of 1-hour daily maximum concentrations. USEPA also 
proposed a new automated Federal Reference Method (FRM) using ultraviolet technology, but will retain 
the older pararosaniline methods until the new FRM have adequately permeated state monitoring 
networks. USEPA also revoked both the existing 24-hour S02 standard of 0.14 ppm and the annual 
primary S02 standard of 0.030 ppm, effective August 23, 2010. The secondary S02 standard was not 
revised at that time; however, the secondary standard is undergoing a separate review by USEPA. Note 
that the new standard is in units of parts per billion (ppb). California standards are in units of parts per 
million (ppm). To directly compare the new primary national standard to the California standard, the 
units can be converted to ppm. In this case, the national standard of 75 ppb is identical to 0.075 ppm. 

10. CARB has identified lead and vinyl chloride as "toxic air contaminants” with no threshold level of 
exposure for adverse health effects determined. These actions allow for the implementation of control 
measures at levels below the ambient concentrations specified for these pollutants. 

11. National lead standard, rolling 3-month average: final rule signed October 15, 2008. 

Source: CARB 2010 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-3 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Ground-level ozone is the primary component of smog. Ozone is formed from the 
interaction of reactive organic gases (ROG] and nitrogen oxides (NOx], ROG is emitted by 
motor vehicles, industrial activities, and consumer products (such as paints, inks, and 
adhesives], NOx is formed during the burning of fossil fuels such as gasoline, diesel fuel, 
coal, and oil. Weather and topography influence the formation and location of ground-level 
ozone. Hot temperatures spur the reaction between volatile organic compounds and 
nitrogen oxides to form ozone. Ground-level ozone settles into valleys when winds are calm 
and temperatures are warm. Sensitive receptors to ozone are the same as those listed for 
particulate matter, with the addition of forests and agricultural crops. 

State Plans, Policies, Regulations, and Laws 

California Air Resources Board 

The California Air Resources Board [CARB] was established in 1967. CARB has set 
California Ambient Air Quality Standards (CAAQSs], presented in Table 3.2-1, that are more 
stringent than the NAAQS for most contaminants. These include standards for additional 
contaminants not covered in the NAAQS, including visibility reducing particles, sulfates, 
hydrogen sulfide, and vinyl chloride. The California Clean Air Act was passed in 1988 and 
requires non-attainment areas to achieve and maintain the CAAQSs by the earliest time 
practicable, and local air districts to develop attainment plans for state standards. 

CARB regulates motor vehicle emissions in the state, while local air quality management 
district's permit stationary sources. 

Regional and Local Plans, Policies, Regulations, and Ordinances 

CARB has designated 15 air basins in the state. Thirty-five local air quality management 
districts are responsible for attainment and permitting in each basin and subbasin area. 
Santa Clara County is located in the San Francisco Bay Area Air Basin. The BAAQMD 
oversees planning and permitting in the nine-county Bay Area, including Santa Clara 
County. 

BAAQMD 2010 Clean Air Plan/BAAQMD CEQA Guidelines 

The BAAQMD adopted a new clean air plan (the Bay Area 2010 Clean Air Plan] in 
September 2010. The purposes of the Bay Area 2010 Clean Air Plan are to: update the Bay 
Area 2005 Ozone Strategy in accordance with the requirements of the California Clean Air 
Act to implement "all feasible measures" to reduce ozone; provide a control strategy to 
reduce ozone, particulate matter (PM], and air toxics in a single, integrated plan; review 
progress in improving air quality in recent years; and establish emission control measures 
to be adopted or implemented in the 2010-2012 timeframe (BAAQMD 2010], 

The BAAQMD published its latest version of the State CEQA Guidelines in May 2011, to aid 
assessment of air quality impacts. The guidelines address evaluation of air quality impacts 
and their significance, and development of mitigation measures for significant impacts. The 
guidelines focus on criteria air pollutant, toxic air contaminant, and odor emissions 
generated from projects. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-4 


December 2011 
Project No. 10.005 



3.2 Air Quality 


3.2.3 Environmental Setting 

Climate and Topography 

Climate and topography dictate the potential for air pollution to build up or concentrate in 
geographic areas. Wind speed, inversions, atmospheric stability, solar radiation, and terrain 
all influence air pollution potential. The actual air quality is a function of the air pollution 
potential and the existing emissions at any given time. 

Wind speed affects air quality because faster winds carry pollutants away from the source. 
Low wind speeds allow more pollutants to be emitted into the air mass per unit of time, 
leading to a buildup of pollutant concentration. Similarly, inversions influence the mass of 
air available for dilution by vertically limiting the distance pollutants can travel. An 
inversion occurs when the typical atmospheric condition of "temperature decreases with 
elevation increases" is reversed, or "inversed." Inversions may result in a layer of warmer 
air resting over a layer of cooler air. The denser cooler air is trapped below the less dense 
warm air. In this inversion situation, pollutants emitted are trapped beneath the warmer air 
aloft within the cooler air lower to the ground. This situation, in combination with reduced 
circulation, reduces opportunities for mixing and dispersion, potentially leading to higher 
pollutant concentrations and poorer air quality. Inversions in the Bay Area may limit the 
pollutant mixing depth of the lower air mass to as little as 50 to 100 meters above the 
ground surface. In the Bay Area, inversions can occur in the winter under conditions of cold, 
clear nights, with damp ground and little wind. Inversions also happen under warmer 
weather conditions when the fog systems keep ground temperatures cooler than the air 
above them. (BAAQMD 2011] 

Atmospheric stability also influences the ability of pollutants to move vertically. Stability is 
defined as the atmosphere's resistance to vertical motions (BAAQMD 2011]. The more 
stable the air, the slower the mixing of pollutants into the air mass. Stability is dependent on 
the temperature gradient with elevation. A stronger standard temperature gradient (with 
temperatures decreasing with elevation increases] increases atmospheric instability and 
mixing. Atmospheric stability can cause reduced pollutant mixing and, therefore, increased 
air pollution potential. 

Solar radiation is necessary for formation of ozone in the atmosphere. Ultraviolet sunlight 
and warm temperatures catalyze the chemical reaction between reactive organic gases and 
nitrogen oxides that form ozone. The frequent hot, sunny days in the Bay Area in the 
summer months promote ozone air pollution, particularly in the inland valleys where 
temperatures are warmest. Insufficient ultraviolet light and warmth in the winter reduce 
the likelihood of forming ozone. (BAAQMD 2011] 

Topography influences air pollution principally through wind and circulation patterns. The 
lee side of mountains may be sheltered from the predominant winds, reducing turbulence 
and downward transport. Elevated terrains can create temperature and density driven 
circulations, with up-valley wind flows during daytime heating and down-valley flows 
during nighttime cooling (BAAQMD 2011], In the Bay Area, typical on-shore regional wind 
patterns from the west and northwest can be reversed by seasonal off-shore flows, 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-5 


December 2011 
Project No. 10.005 



3.2 Air Quality 


generating northeasterly and easterly winds. Winter cyclonic storms may bring southerly 
winds. 

San Francisco Bay Air Subbasins 

The BAAQMD divides the San Francisco Bay Area Air Basin into subbasins with distinct 
climate and topography. Two air subbasins occupy Santa Clara County—the Peninsula and 
the Santa Clara Valley subbasins. The peninsula region of the Bay Area extends from the 
area northwest of San Jose to the Golden Gate, with the Santa Cruz Mountains extending up 
the center of the peninsula and terminating in South San Francisco. Small coastal towns on 
the west side of the mountains experience a high incidence of cool, foggy weather in the 
summer resulting from coastal ocean upwelling and northwest winds. Larger cities in the 
southeastern area of the peninsula, on the east side of the mountain range, experience 
warmer temperatures and few foggy days because the marine layer is blocked by the 
mountains to the west. Annual average wind speeds range from 5 to 10 miles per hour 
throughout the peninsula. On the east side of the mountains, the winds are generally in a 
westerly pattern, although the wind patterns are influenced by local topographic features. 
The blocking effect of the Santa Cruz Mountains results in higher temperatures in the 
eastern areas, with summertime maximum temperatures at Redwood City, representing the 
eastern peninsula, in the low 80s. The average minimum temperature in Redwood City is 
40°F in the winter and 52-54°F in the summer. Air pollution potential is highest along the 
southeastern portion of the peninsula because this area is most protected from the high 
winds and fog of the marine layer, the emission density is relatively high, and pollutant 
transport from upwind sites is possible. (BAAQMD 2009b] 

The Santa Clara Valley subregion is bounded by the Santa Cruz Mountains to the west, the 
Diablo Range to the east, the San Francisco Bay to the north, and the convergence of the 
Gabilan Range and the Diablo Range to the south. The terrain of the Santa Clara Valley 
greatly influences the wind patterns and results in a prevailing flow roughly parallel to the 
Valley's northwest-southeast axis, with a north-northwesterly sea breeze extending up the 
valley during the afternoon and early evening and a light south-southeasterly drainage flow 
occurring during the late evening and early morning. Speeds are greatest in the spring and 
summer. The strongest winds generally occur during summer afternoon and evenings, 
although strong winds typically only occur during winter storms. In the summer, 
temperatures are warm during the day, with mostly cool nights. Near the San Jose airport, 
mean maximum temperatures range from the high 70s to the low 80s in the summer, and 
from the high 50s to the low 60s during the winter. Mean minimum temperatures are in the 
low 40s during the winter and in the high 50s during the summer. Further inland areas to 
the south may have greater temperature extremes because the moderating effect of the Bay 
is not as strong. Santa Clara Valley has a high air pollution potential because of the valley's 
large population; the transport of photochemical precursors from surrounding counties to 
the valley area; and the concentration of pollutants that occurs in the valley from the 
bordering mountains, winter inversions, and low-inversion summer days. (BAAQMD 
2009b] 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-6 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Air Quality Attainment Status 

Air quality is a function of the climate, topography, and emissions in any area or upwind of 
that area. Table 3.2-2 presents the attainment status of the state and federal standards in 
the Bay Area. The San Francisco Bay Area Air Basin (SFBAAB], including Santa Clara County, 
is in attainment for carbon monoxide, nitrogen dioxide, sulfur dioxide, and lead pollutant 
standards. However, the SFBAAB is in non-attainment for the ozone and particulate matter 
national and state standards. In 2005, the BAAQMD completed an ozone strategy to 
implement all feasible measures to reduce ozone. This strategy was updated by the 
requirements of the 2010 Clean Air Plan to provide a control strategy to reduce particulate 
matter. (BAAQMD 2010] 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-7 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Table 3.2-2. Bay Area Attainment Status of the State and Federal Ambient Air Quality Standards 




State 


Contaminant 

Averaging Time 

Standards 

Attainment 

Federal Standards 
Attainment Status 2 



Status 1 


Ozone 

1-hour 

N 

See note 4 

8-hour 

N 7 

N 3 

Respirable Particulate Matter (PM 10 ) 

24-hour 

N 

U 

Annual arithmetic mean 

N 6 


Fine Particulate Matter (PM 2 . 5 ] 

24-hour 


N 

Annual arithmetic mean 

N 6 

A 

Carbon Monoxide 

8-hour 

A 

A 5 

1-hour 

A 

A 

Nitrogen Dioxide 

Annual arithmetic mean 


A 

1-hour 

A 

U 

Sulfur Dioxide 

24-hour 

A 

A 

1-hour 

A 


Lead 

30-day average 

A 


Calendar quarter 


A 

Visibility Reducing Particles 

8-hour 

U 


Sulfates 

24-hour 

A 


Hydrogen Sulfide 

1-hour 

U 


Vinyl Chloride 

24-hour 

Not available 



A - attainment 

N - non-attainment 

U - unclassified 

Notes: 

1. California standards for ozone, carbon monoxide (except Lake Tahoe), sulfur dioxide (1-hour and 24-hour), nitrogen 
dioxide, suspended particulate matter—PM10, and visibility reducing particles are values that are not to be 
exceeded. The standards for sulfates, Lake Tahoe carbon monoxide, lead, hydrogen sulfide, and vinyl chloride are not 
to be equaled or exceeded. If the standard is for a 1-hour, 8-hour, or 24-hour average (i.e., all standards except for 
lead and the PM10 annual standard), then some measurements may be excluded. In particular, measurements are 
excluded that CARB determines would occur less than once per year on the average. The Lake Tahoe CO standard is 
6.0 ppm, a level one-half the national standard and two-thirds the state standard. 

2. National standards shown are the "primary standards" designed to protect public health. National standards other 
than for ozone, particulates and those based on annual averages are not to be exceeded more than once a year. The 
1-hour ozone standard is attained if, during the most recent 3-year period, the average number of days per year with 
maximum hourly concentrations above the standard is equal to or less than one. The 8-hour ozone standard is 
attained when the 3-year average of the 4th highest daily concentrations is 0.075 ppm (75 ppb) or less. The 24-hour 
PM10 standard is attained when the 3-year average of the 99th percentile of monitored concentrations is less than 
150 pg/m 3 . The 24-hour PM 2 .S standard is attained when the 3-year average of 98th percentiles is less than 

35 pg/m 3 . Except for the national particulate standards, annual standards are met if the annual average falls below 
the standard at every site. The national annual particulate standard for PM10 is met if the 3-year average falls below 
the standard at every site. The annual PM2.5 standard is met if the 3-year average of annual averages spatially- 
averaged across officially designed clusters of sites falls below the standard. 

3. In June 2004, the Bay Area was designated as a marginal non-attainment area of the national 8-hour ozone standard. 
USEPA lowered the national 8-hour ozone standard from 0.80 to 0.75 PPM (i.e., 75 ppb) effective May 27, 2008. 
USEPA will issue final designations based upon the new 0.75 ppm ozone standard by July 31, 2011. 

4. The national 1-hour ozone standard was revoked by USEPA on June 15, 2005. 

5. In April 1998, the Bay Area was redesignated to attainment for the national 8-hour carbon monoxide standard. 

6. In June 2002, CARB established new annual standards for PM2.5 and PM10. 

7. The 8-hour California ozone standard was approved by CARB on April 28, 2005, and became effective May 17, 2006. 

Source: BAAQMD 2009a _ 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-8 


December 2011 
Project No. 10.005 



3.2 Air Quality 


3.2.4 Impact Analysis 

Methodology 

Although existing SMP and proposed maintenance activities are and would be widespread, 
transitory, and short-term in nature, similar to construction activities, they serve and would 
continue to serve the purpose of maintaining existing features rather than constructing new 
features. Based on discussions with the BAAQMD, the BAAQMD's operational CEQA 
thresholds for projects are most appropriate for the Proposed Project (Michael, pers. 
comm., 2010], 

Air emissions from proposed maintenance activities were estimated for three sources: 
off-road vehicles, on-road vehicles, and pesticide use. Off-road vehicle emissions were 
estimated using equipment data and CARB’s OFFROAD 2007 model. On-road vehicle 
emissions were estimated using vehicle miles traveled (see Section 3.12, Traffic and 
Transportation ] and CARB's Emissions Factors 2007 model. Pesticide use was based on a 
4-year average (2007-2010] of SCVWD's pesticide use and the percentage of ROG in each 
pesticide, as identified in the California Department of Pesticide Regulation's Pesticide 
Volatile Organic Compound Emission Inventory. For a list of the type and quantity of 
pesticides used under the existing SMP, refer to Tables 3.6-1 and 3.6-2 in Section 3.6, 
Hazards and Hazardous Materials. 

Criteria for Determining Significance 

For the purposes of this analysis, the Proposed Project would result in a significant impact 
on air quality if it would: 

A. conflict with or obstruct implementation of applicable air quality plans; 

B. exceed any air quality standard by failing to adhere to assumptions used in the 
preparation of any Air Quality Plans; 

C. result in a cumulatively considerable net increase of any criteria pollutant for which 
the project region is non-attainment under an applicable federal or state ambient air 
quality standard (including releasing emissions which exceed quantitative 
thresholds for ozone precursors]; 

D. expose sensitive receptors to substantial pollutant concentrations; or 

E. create objectionable odors affecting a substantial number of people. 

Table 3.2-3 provides the BAAQMD's recommended significance criteria for analysis of air 
quality impacts. Based on discussions with the BAAQMD, the BAAQMD's operational CEQA 
thresholds for projects are most appropriate for the Proposed Project (Michael, pers. 
comm., 2010], 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-9 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Emissions associated with the Proposed Project were estimated for the various SMP 
activities as a whole; for this reason, the impact discussion in this section relative to 
Significance Criteria A through D is not broken down by the individual categories of 
maintenance activities. 


Table 3.2-3. BAAQMD CEQA Thresholds of Significance for Criteria Air Pollutants 


Criteria Air Pollutants and Precursors 
(Regional) 

Operational Thresholds 

Average Daily Emissions (lb/day) 

Maximum Annual 
Emissions (tpy) 

Reactive Organic Gases (ROG) 

54 

10 

Nitrogen oxides (NOx) 

54 

10 

Particulate Matter (PMio) 

82 

15 

Particulate Matter (PM 2 . 5 ) 

54 

10 

PM 10 /PM 2.5 (fugitive dust) 

None 

Local Carbon Monoxide (CO) 

9.0 ppm (8-hour average), 20.0 ppm (1-hour average) 

Risk and Hazards for new sources and 
receptors (Individual Project) Note: 

Threshold for new receptors is effective 

May 1,2011. 

Compliance with Qualified Community Risk Reduction Plan OR 

• Increased cancer risk of >10.0 in a million 

• Increased non-cancer risk of > 1.0 Hazard Index 
(Chronic or Acute) 

• Ambient PM 2.5 increase: > 0.3 gg/m 3 annual average 
Zone of Influence: 1.000-foot radius from property line of 
source or receptor 

Risk and Hazards for new sources and 
receptors (Cumulative Threshold). Note: 
Threshold for new receptors is effective 

May 1,2011. 

Compliance with Qualified Community Risk Reduction Plan OR 

• Cancer risk: >100 million (from all local sources) 

• Non-cancer risk: > 10.0 Hazard Index (from all local 
sources, Chronic) 

• Ambient PM 2 . 5 : > 0.8 gg/rn 3 annual average (from all 
local sources) 

Zone of Influence: 1.000-foot radius from property line of 
source or receptor 

Accidental Release of Acutely Hazardous 

Air Pollutants 

Storage or use of acutely hazardous materials located near 
receptors or new receptors located near stored or used acutely 
hazardous materials considered significant 

Odors 

Five confirmed complaints per year averaged over 3 years 


tpy - tons per year; lb/day - pounds per day; ppm - parts per million 
Source: BAAQMD 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-10 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Environmental Impacts 

Impact AIR-1: Temporary Increase in ROG, NOx, PM 10 , and PM 2 .s Emissions during 
Maintenance Activities (Significance Criteria A, B, C, D; Less than Significant with 
Mitigation or Significant and Unavoidable) 

Conducting the Proposed Project maintenance activities would generate emissions of 
criteria air pollutants. In particular, soil disturbance would cause temporary emissions of 
particulate matter. Fuel combustion involved with operating heavy equipment and on-road 
vehicles used to dispose debris also would release particulate matter and other 
contaminants associated with motor vehicle operation, including carbon monoxide and 
ozone precursors (ROG and NOx], Finally, use of pesticides would result in emissions of 
ROG. 

This analysis considers emissions from both existing SMP activities (conducted pursuant to 
the 2002 SMP EIR] and additional emissions resulting from implementation of the Proposed 
Project (SMP update from 2012 to 2022], The existing SMP allows the majority of 
maintenance activities to be conducted between June 15 and October 15, although some 
activities occur year-round. The Proposed Project would extend the potential period when 
maintenance activities could be conducted (for those not occurring year-round], from 
October 15 to December 31. The overall work that would be conducted within the work 
window of the existing SMP is not anticipated to increase; rather, all additional work would 
occur during the extended work window. 

Table 3.2-4 summarizes average daily operational emissions for 2012 and 2020 and Table 
3.2-5 summarizes annual emissions estimates for 2012 and 2020. For additional 
information on how emissions were estimated refer to Appendix E. Although daily vehicle 
activity would not change substantially between 2012 and 2020, daily emissions are 
expected to decrease because turnover of fleet vehicles would replace higher-emitting 
vehicles with lower-emitting ones. Consequently, average daily vehicle emissions will be 
much lower in 2020 compared to 2012. Annual emissions from the Proposed Project 
compared to the existing SMP would increase corresponding to the increase in the number 
of work days per year, or twenty-five percent. This increase is offset by the decrease in 
emissions associated with fleet vehicle turnover. 


Table 3.2-4. Estimated Proposed Project Average Daily Emissions of Criteria Air 
Pollutants, pounds per day 


Emissions Source 

ROG 

NOx 

PM 10 

PMz.5 

2012 

2020 

2012 

2020 

2012 

2020 

2012 

2020 

Off-Road 

44.2 

25.7 

388.3 

138.1 

16.3 

5.4 

16.3 

5.4 

On-Road 

6.1 

3.5 

45.7 

20.0 

16.4 

16.6 

4.0 

3.6 

Pesticide Use 

0.6 

0.6 

- 

- 

- 


- 


Total 

50.9 

29.7 

434.0 

158.1 

32.8 

22.0 

20.4 

9.0 

BAAQMD Threshold 

54 

54 

82 

54 


Note: Daily vehicle trips and vehicle miles traveled would remain the same in the SMP Update as in the existing SMP. 
Source: Data compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-11 


December 2011 
Project No. 10.005 




















3.2 Air Quality 


Table 3.2-5. Estimated Proposed Project Annual Emissions of Criteria Air Pollutants, 
tons per year 


Emissions Source 

ROG 

NOx 

PM 10 

PM 2 .5 

2012 

2020 

2012 

2020 

2012 

2020 

2012 

2020 

Existing SMP 

Off-Road 

1.9 

1.1 

16.5 

5.9 

0.7 

0.2 

0.7 

0.2 

On-Road 

0.8 

0.5 

5.9 

2.6 

2.1 

2.2 

0.5 

0.5 

Pesticide Use 

0.0 

0.0 

- 

- 

- 


- 


Total 

2.7 

1.6 

22.4 

8.5 

2.8 

2.4 

1.2 

0.7 


Additional Emissions under the SMP Update (2012-2022) 


Off-Road 

On-Road 

Pesticide Use 

0.5 

0.1 

0.0 

0.3 

0.0 

0.0 

4.1 

1.2 

1.5 

0.2 

0.2 

0.1 

0.1 

0.0 

0.2 

0.1 

0.1 

0.0 

Total 

0.6 

0.3 

5.4 

1.7 

0.3 

0.1 

0.2 

0.1 


Total SMP 


Off-Road 

On-Road 

Pesticide Use 

2.3 

0.9 

0.0 

1.4 

0.5 

0.0 

20.6 

7.2 

7.3 

2.8 

0.9 

2.3 

0.3 

2.2 

0.9 

0.6 

0.3 

0.5 

Total 

3.3 

1.9 

27.8 

10.2 

3.1 

2.5 

1.4 

0.8 

BAAQMD Threshold 1 

10 

10 

15 

10 


Note: 

1. See Table 3.2-3 for BAAQMD CEQA Thresholds of Significance for criteria air pollutants. 
Source: Data compiled by Horizon Water and Environment in 2011 


Table 3.2-4 shows that average daily emissions of criteria air pollutants from the SMP 
would be below BAAQMD construction significance thresholds, except for NOx. Table 3.2-5 
shows that annual emissions of criteria air pollutants from the Proposed Project would be 
less than BAAQMD operational significance thresholds, except for NOx. 

Applicable Best Management Practices 

The following BMPs would be implemented as part of the SMP Update to control dust 
during maintenance activities. Descriptions of each BMP are provided in Chapter 2, Project 
Description. 

BMP GEN-4: Minimize the Area of Disturbance 
BMP GEN-29: Dust Management 

Conclusion 

Although emissions of criteria air pollutants other than NOx from the SMP would occur at 
levels below BAAQMD significance thresholds, implementation of BMPs would minimize 
PMio and PM2.5 emissions. Average daily and annual emissions of NOx from the SMP would 
be substantially greater than BAAQMD significance thresholds throughout the SMP. NOx 
emissions in exceedance of BAAQMD significance thresholds are considered a potentially 
significant impact. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-12 


December 2011 
Project No. 10.005 























































3.2 Air Quality 


The District would implement Mitigation Measure AIR-1A, reducing NOx emissions by 20 
percent, which would lower NOx emissions below the significance threshold in 2020, but 
not in 2012. As a result, this impact would remain significant after this mitigation. 

Therefore, the District would implement either Mitigation Measure AIR-1B or AIR-1C to 
offset remaining annual NOx emissions in exceedance of BAAQMD significance thresholds. 
Implementation of either Mitigation Measure AIR-1B or AIR-1C would reduce this impact to 
a less than significant level. However, it is possible that these mitigation measures may not 
be feasible because of the considerations discussed below. If the District found these 
mitigation measures to be infeasible, then this impact would be considered significant and 
unavoidable. 

Mitigation Measure A1R-1A Reduction in Fleet Emissions 

The District will develop a plan to demonstrate that the off-road equipment (more 
than 50 horsepower] to be used in the SMP Update (i.e., owned, leased, and 
subcontractor vehicles] would achieve a project-wide, fleet-average 20 percent NOx 
reduction compared to the most recent ARB fleet average. Acceptable options for 
reducing emissions include the use of late-model engines, low-emission diesel 
products, alternative fuels, engine retrofit technology, after-treatment products, 
add-on devices (such as particulate filters], and/or other options as they become 
available. 

Mitigation Measure AIR-1B Off-site NOx Emissions Mitigation Program 

SCVWD may establish a program to implement off-site NOx emissions reduction 
projects within the SFBAAB to reduce those NOx emissions from the SMP Update in 
exceedance of BAAQMD operational significance thresholds. The total reduction will 
be 9 tons (the average annual exceedance anticipated over the lifetime of the SMP 
Update, based on the average between estimated 2012 and 2020 emissions], as 
adjusted based on the emissions reductions to be achieved by Mitigation Measure 
AIR-1A. The NOx emission reductions projects will be from sources of emissions 
that are not required by any existing law to reduce their NOx emissions. Offsetting 
annual emissions inherently includes offsetting daily emissions. Therefore, no 
additional reductions will be required for daily NOx emissions. Documentation of 
off-site NOx reductions will be provided to the BAAQMD. 

However, it is possible that this mitigation measure may not be feasible, based on costs, 
logistics, or other factors. In respect to logistics, whether the District could develop a new 
off-site mitigation program that effectively reduces emissions to less-than-significant levels 
in a timely manner is uncertain. 

Mitigation Measure AIR-1C NOx Emissions Offsets 

As an alternative to Mitigation Measure AIR-IB, SCVWD will purchase NOx emission 
reduction credits to reduce or offset those NOx emissions in exceedance of BAAQMD 
operational significance thresholds. The total reduction (or credits] will be 9 tons, as 
adjusted based on the emissions reductions achieved by Mitigation Measure AIR-1A. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-13 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Offsetting annual emissions inherently includes offsetting daily emissions. 

Therefore, no additional offsets will be required for daily NOx emissions. 

SCVWD will engage a private broker to facilitate the purchase of credits through the 
BAAQMD emissions bank. Purchase of these credits from the BAAQMD emissions 
bank will ensure that NOx offsets occur in the SFBAAB. Once NOx emission 
reduction credits are purchased for a given quantity, that amount of NOx will be 
offset in perpetuity. Therefore, a one-time purchase of 9 tons of credits will mitigate 
for the duration of the SMP Update (2012-2022] as well as for future SMP-related 
emissions beyond 2022, assuming emissions will not have increased. 

Documentation of purchased NOx offsets will be provided to the BAAQMD. 

However, it is possible that this mitigation may not be feasible, based on costs or other 
factors. 

Impact AIR-2: Diesel PM Health Risk during Maintenance Activities 
(Significance Criteria A, B, C, D; Less than Significant) 

Exhaust emissions from on- and off-road vehicles and equipment used for maintenance 
under the Proposed Project would generate diesel PM, a toxic air contaminant. Individual 
maintenance activities would last from one day to several weeks. These maintenance 
activities would be countywide, transitory, and short term, and when they have ceased, so 
would associated diesel PM emissions. 

Applicable Best Management Practices 

The following BMP would be implemented as part of the SMP Update, and would help to 
minimize Diesel PM emissions. A description of the BMP is provided in Chapter 2, Project 
Description. 

BMP GEN-35: Pump/Generator Operations and Maintenance 


Conclusion 

Health risk assessments for diesel PM are typically based on 9-, 40-, and 70-year exposure 
periods. Because of the short-term and highly variable nature of diesel PM emissions 
associated with the Proposed Project, exposure to diesel exhaust, including for sensitive 
receptors, would be well below the exposure period of concern. Therefore, exposure of 
persons to diesel PM generated by the Proposed Project would be less than significant and 
no mitigation would be required. 

Mitigation Measures: No mitigation is required. 

Impact AIR-3: Creation of Objectionable Odors 
(Significance Criterion E; Less than Significant) 

Sediment removal is the only activity in the Proposed Project which has the potential to 
generate substantial objectionable odors. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-14 


December 2011 
Project No. 10.005 



3.2 Air Quality 


Sediment Removal 

Excavated sediment from stream channels may contain high levels of organic material. 
Natural decomposition of organic material depletes oxygen in the subsurface environment, 
leading to anaerobic conditions and the generation of hydrogen sulfide. Hydrogen sulfide 
gas then may be released when sediment is excavated. The potential concentrations of 
hydrogen sulfide gas released from sediment removal activities would not be substantial 
enough to adversely affect human health; however, they could cause annoyance by creating 
an objectionable odor in the vicinity of a specific maintenance/stockpile work site or 
reuse/disposal location. The intensity of odor from excavated sediment would depend on 
the amount and quality of sediment. 

Conclusion 

The BAAQMD indicates that odor impacts could result from siting a new odor source near 
existing sensitive receptors. However, SCVWD is not aware of instances under the existing 
SMP when excavated or stockpiled sediment has generated odors that have created an 
annoyance. Conditions are anticipated to be substantively similar under the SMP Update. 
Any odors, should they occur, would be localized, short-term, and would not be anticipated 
to affect a substantial number of people. Therefore, the impact from creation of 
objectionable odors would be less than significant and no mitigation would be required. 

Mitigation Measures: No mitigation is required. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 2012-2022 

Final Subsequent Environmental Impact Report 


3.2-15 


December 2011 
Project No. 10.005 




Chapter 3.3 


Biological Resources 





3.3 Biological Resources 

3.3.1 Introduction 

This section presents the regulatory setting, environmental setting, and potential impacts of 
the Proposed Project related to biological resources. The section describes existing 
biological conditions in the Project Area and changes to the SMP and biological resources 
since 2002. 

To identify biological resources, a number of documents were collected and reviewed 
including: the Final Environmental Impact Report for the Multi-Year Stream Maintenance 
Program (SCVWD 2002a], the 2002 Stream Maintenance Program (SCVWD 2002b], the 
2012 Stream Maintenance Project Description (SCVWD 2010], SMP post-construction 
reports (SCVWD 2002d, 2003b, 2004b, 2005b, 2006b, 2007c, 2008b, and 2009b], and the 
2002-2009 SMP fish relocation reports (SCVWD 2002c, 2003a, 2004a, 2005a, 2006a, 
2007a, 2007b, 2008a, and 2009a], Data on special-status species occurrences compiled by 
SCVWD since 2001 were collected and reviewed: Rarefind data (CNDDB 2011]; California 
wildlife habitat relationships information (CDFG 2008a]; the Breeding Bird Atlas of Santa 
Clara County (Bousman 2007h]; California Bird Species of Special Concern (Shuford and 
Gardali 2008]; information available through the USFWS, including a list of special-status 
species potentially occurring in Santa Clara County; and other technical publications and 
previous reports. 

All California Native Plant Society (CNPS] lists (CNPS 2011] and applicable records were 
reviewed to determine the potential for occurrence of special-status plant species in the 
Project Area. The Jepson Manual (Hickman 1993] supplied information regarding the 
distribution and habitats of vascular plants in Santa Clara County. In addition, the habitat- 
level ("land cover"] and vegetation association descriptions in the working draft of the 
Santa Clara Valley Habitat Conservation Plan/Natural Communities Conservation Plan 
(Habitat Plan; ICF Jones & Stokes 2010] provided some indication of the potential locations 
of special-status plants. 

SCVWD routinely conducts a variety of surveys and monitoring efforts that provide 
information on the presence and distribution of sensitive communities and plant and 
animal species, including special-status species and their habitats in SCVWD's service area. 
The following discussion summarizes information collected during the review, used to 
determine the environmental setting for the Proposed Project. A number of the studies used 
to compile the baseline biological conditions were performed prior to the publication of the 
Notice of Preparation (31 August 2010]; such studies were used to inform the description of 
baseline conditions if they contributed relevant information regarding baseline biological 
conditions. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-1 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Vegetation Mapping 

Aerial Information Systems, Inc. (AIS] conducted vegetation mapping of streams and canals 
in the Project Area in 2010. Vegetation units were mapped using aerial photo interpretation 
and interactive computer digitization methods. The vegetation classification system was 
based on A Manual of California Vegetation (Sawyer et al. 2009], Each vegetation unit was 
coded to the group level (alliance level where possible] and assigned a cover class density 
for the vegetation type mapped. This mapping involved a reconnaissance-level field visit to 
match preliminary aerial photo signatures with vegetation types on the ground before 
photo interpretation, as well as spot-checking of selected areas in the field after preliminary 
photo interpretation to verify the accuracy of mapping of certain vegetation types. In 
addition, in 2004 and 2008, SCVWD botanist J. Hillman surveyed SMP-maintained creeks 
and canals within serpentine communities and mapped high-quality examples of these 
communities. 

Special-Status Plant Surveys 

In 2004 and 2008 as part of the Biodiversity Monitoring Program, SCVWD conducted 
mapping of comprehensive botanical surveys for serpentine soils on all its creeks and 
canals, determined by overlaying U.S. Soil Conservation Service (USSCS, now the Natural 
Resources Conservation Service] and U.S. Geologic Survey (USGS] maps of serpentine soils 
on the Project Area map. That overlay indicated that 15.3 miles of canals were found to 
traverse serpentine soils and associated bedrock, as evidenced by associated plant species, 
vegetation types, and soil analysis (SCVWD unpublished data]. During the 2004 and 2008 
botanical surveys, 44 populations or partial populations of six special-status plant species 
were mapped by SCVWD botanist J. Hillman along the Almaden Calero Canal, Coyote 
Alamitos Canal, Coyote Canal, and Coyote Canal Extension. In contrast, no special-status 
plants were documented along any natural creeks in serpentine-dominated areas. 

Fisheries Surveys 

SCVWD has collected fish species distribution, occurrence, and abundance data for a variety 
of projects and conducted several types of fisheries surveys to meet specific information 
needs. Such surveys have included conducting habitat typing of fish assemblages at index 
reaches, and collecting data on species presence, disposition, and abundance at relocation 
sites. Fish relocations have been performed at various SMP work sites (see Table 3.3-1] 
throughout the past 9 years of the SMP (SCVWD 2002c, 2003, 2004, 2005, 2006, 2007a, 
2007b, 2008, and 2009], Fish species, disposition, and abundance data were collected at 
each of these sites, and summaries of the fish captured and released (natives] or sacrificed 
(non-natives] were prepared for each year. Other general surveys related to habitat quality 
for salmonids have included the collection of hourly stream temperatures and bi-monthly 
reservoir profiles at certain locations, evaluating creeks to determine if they are ephemeral, 
and mapping passage impediments on some creeks. Examples of studies conducted by 
SCVWD that provide information on fish use of SMP creeks are listed in Table 3.3-2. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-2 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Table 3.3-1. Fish Relocation Creeks 


Adobe Creek 

Guadalupe River 

Permanente Creek 

Alamitos Creek 

Hale Creek 

Ross Creek 

Berryessa Creek 

Llagas Creek 

San Tomas Aquino Creek 

Calabazas Creek 

Los Coches Creek 

Saratoga Creek 

Calero Creek 

Lower Penitencia Creek 

Stevens Creek 

Coyote Creek 

Lower Silver Creek 

Sunnyvale East Channel 

Greystone Creek 

Matadero Creek 

Upper Penitencia Creek 

Guadalupe Creek 

Mistletoe Creek 

Wildcat Creek 


Source: Compiled by Horizon Water and Environment in 2011 


Table 3.3-2. Selected Recent SCVWD Fisheries Studies 


Title 

Year 

Santa Clara Valley Water District Upmigrant and Outmigrant Trapping 
Operations for the Guadalupe River, Coyote Creek, and Stevens Creek 

1998-2005 

Santa Clara Valley Water District Guadalupe River Project Mitigation 
Monitoring Report 

2000-2010 

Fish Relocations for Stream Maintenance Program 

2002-2009 

Provenance Analysis of Chinook Salmon (Oncorhynchus tshawytscha ] in the 
Santa Clara Valley Watershed 

2002 

Chinook Radio Tracking Report, Guadalupe River Watershed, 2003-2004 

2004 

Mid-Coyote Flood Protection Project Baseline Fisheries Monitoring Report 

Year 1 [2007] 

2007 

Population Genetics of Oncorhynchus mykiss in the Santa Clara Valley Region 

2008 

Mid-Coyote Creek Flood Protection Project Baseline Fisheries Monitoring 
Report Year 2 [2008] 

2009 

Lenihan Dam Outlet Modifications Project Fisheries Sampling Update, Project 
No. 91904005 

2009 


Source: Compiled by Horizon Water and Environment in 2011 


California Red-legged Frog Surveys 

Between 1996 and 2001, SCVWD surveyed portions of the Project Area for California red- 
legged frogs (Rana draytonii), following the 1997 USFWS protocol (USFWS 1997], 
Approximately 80 percent of the streams in the Project Area with suitable habitat and 
accessible to SCVWD were surveyed. Areas in the foothills and mountain ranges were less 
thoroughly surveyed because of difficulty accessing private land. SCVWD concluded that 
most of the County's ephemeral creeks do not support red-legged frog breeding habitat 
because of the absence of surface water during the tadpole-rearing season. Since 2001, 
SCVWD has conducted surveys for red-legged frogs in the context of pre-activity surveys for 
SMP activities. Furthermore, since 2004, annual surveys for the presence or absence of 
special-status amphibians have been conducted in numerous locations before the 
application of instream herbicides (see Table 3.3-3]; no special-status amphibians were 
found at any of the locations listed in Table 3.3-3. These data sets were reviewed as part of 
the preparation of this document. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-3 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Table 3.3-3. Locations of Pre-Construction Presence/Absence Surveys for Special-Status 
Amphibians, 2004-2010 


Creek Name 

Creek Stationing 

Creek Name 

Creek Stationing 

To 

From 

To 

From 

Adobe Creek 

132+00 

250+00 

North Babb Creek 

42+00 

55+00 

Alamitos Creek 

21+55 

232+00 

Norwood Creek 

0+00 

32+00 

Barron Creek 

0+00 

105+00 

Penitencia East 
channel 

0+00 

36+00 

Berryessa Creek 

0+00 

297+00 

Permanente Creek 

70+00 

383+00 

Calabazas Creek 

20+00 

447+30 

Permanente diversion 

0+00 

71+00 

Calera Creek 

9+00 

60+00 

Piedmont Creek 

0+00 

26+00 

Canoas Creek 

0+00 

390+00 

Prospect Creek 

0+00 

20+00 

Coyote Creek 

480+00 

776+00 

Quirnby Creek 

0+00 

38+00 

Daves Creek 

12+00 

14+00 

RandolCreek 

0+00 

89+00 

Deer Creek 

0+00 

17+00 

Regnart Creek 

0+00 

66+00 

Deer Creek 

74+00 

91+00 

Rodeo Creek 

0+00 

100+00 

El Camino storm drain 

0+00 

20+00 

Ross Creek 

3+00 

236+00 

Flint Creek 

0+00 

20+00 

Ruby Creek 

0+00 

20+00 

Golf Creek 

0+00 

70+00 

South Babb Creek 

0+00 

45+00 

Greystone Creek 

0+00 

70+00 

San Tomas Aquino 
Creek 

26+00 

224+00 

Guadalupe Creek 

1050+00 

1130+00 

San Tomas Aquino 
Creek 

430+00 

670+00 

Guadalupe River 

220+00 

1044+00 

Saratoga Creek 

0+00 

280+00 

Hale Creek 

0+00 

60+00 

Sierra Creek 

0+00 

63+00 

Heney Creek 

0+00 

52+00 

Smith Creek 

0+00 

92+00 

Junipero Serra channel 

0+00 

132+00 

Stevens Creek 

88+00 

410+00 

Lone Hill Creek 

0+00 

20+00 

Summerhill Creek 

0+00 

5+00 

Los Coches Creek 

0+00 

62+00 

Sunnyvale east 
channel 

22+00 

315+00 

Los Gatos Creek 

0+00 

420+00 

Sunnyvale west 
channel 

44+00 

140+00 

Lower Silver Creek 

0+00 

318+00 

Thompson Creek 

0+00 

65+00 

Lower Silver Creek 

370+00 

380+68 

Tularcitos Creek 

1+00 

36+00 

Lower Penitencia Creek 

0+00 

216+00 

Upper Penitencia 

Creek 

35+00 

65+00 

Matadero Creek 

95+00 

200+00 

Upper Penitencia 

Creek 

72+00 

115+00 

Miguelita Creek 

12+00 

44+00 

Upper Silver Creek 

0+00 

63+00 

North Babb Creek 

0+00 

15+00 





Source: Compiled by Horizon Water and Environment in 2011 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-4 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Bird Surveys 

SCVWD has conducted surveys for the California clapper rail ( Rallus longirostris obsoletus), 
least Bell’s vireo ( Vireo bellii pusillus ], western snowy plover ( Charadrius alexandrinus 
nivosus), and burrowing owl (Athene cunicularia ] in various parts of the county since the 
mid-1990s. California clapper rail surveys have been conducted before maintenance 
activities in suitable habitat since 1996. Beginning in 1997, least Bell’s vireo surveys were 
conducted annually (except in 2005, 2007, and 2008] during the breeding season along 
lower Llagas Creek, and occasionally along sections of Uvas Creek (Padley 2010, H. T. 
Harvey & Associates 2010b], Surveys for western snowy plovers have been conducted at 
potential work sites that contain suitable habitat, including ponds A4, A5, and A8 (Ryan 
2000 ], 

In 2007 and 2008, EDAW conducted a habitat assessment, burrow mapping study, and 
standardized protocol surveys for the burrowing owl along sections of multiple SCVWD- 
managed waterways in Palo Alto, Mountain View, Sunnyvale, Santa Clara, San Jose, Alviso, 
Milpitas, and Gilroy (EDAW 2008], In these areas, 236,214 linear feet of potential burrowing 
owl habitat along SCVWD waterways were assessed. The study was performed under 
SCVWD's Biodiversity Monitoring Program and was designed to monitor burrowing owl 
distribution, abundance, and trends in the Project Area. 

Numerous surveys for nesting birds have been conducted for SCVWD compliance with the 
Migratory Bird Treaty Act. Surveys have occurred throughout Santa Clara County, but 
generally below the 1,000-foot elevation where SCVWD activities routinely occur. These 
surveys have investigated potential habitat for all special-status bird species. 

3.3.2 Regulatory Setting 

A number of federal, state, and local laws and ordinances regulate biological resources. 
Described next are the pertinent statutes and regulations. 

Federal Plans, Policies, Regulations, and Laws 

Clean Water Act 

Areas meeting the regulatory definition of "waters of the U.S." (jurisdictional waters] are 
subject to the jurisdiction of the U.S. Army Corps of Engineers (USACE] under provisions of 
Section 404 of the 1972 Clean Water Act (federal Water Pollution Control Act] and/or 
Section 10 of the 1899 Rivers and Harbors Act (described below]. These waters may include 
all waters used, or potentially used, for interstate commerce, including all waters subject to 
the ebb and flow of the tide, all interstate waters, all other waters (intrastate lakes, rivers, 
streams, mudflats, sandflats, playa lakes, natural ponds], all impoundments of waters 
otherwise defined as "waters of the U.S.,” tributaries of waters otherwise defined as "waters 
of the U. S.,” territorial seas, and wetlands (termed Special Aquatic Sites] adjacent to "waters 
of the U.S." (33 Code of Federal Regulations [CFR], Part 328, Section 328.3], Wetlands on 
non-agricultural lands are identified using the Corps of Engineers Wetlands Delineation 
Manual (Environmental Laboratory 1987], 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-5 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Areas typically not considered jurisdictional waters include non-tidal drainage and 
irrigation ditches excavated on dry land, artificially irrigated areas, artificial lakes or ponds 
used for irrigation or stock watering, small artificial water bodies such as swimming pools, 
and water-filled depressions (33 CFR, Part 328], Canals subject to SMP activities are not 
expected to be jurisdictional because they were excavated in uplands and do not function as 
navigable waters or tributaries to navigable waters]. Furthermore, the canals that are 
currently not in operation (Coyote, Coyote Extension, and Coyote Alamitos] do not carry 
water at all, other than runoff that is intercepted from upslope upland areas. However, 
whether or not the canals subject to SMP Update activities are jurisdictional waters of the 
U.S. is to be determined by the USACE. 

Construction activities within jurisdictional waters are regulated by the USACE, and 
placement of fill into such waters must comply with USACE permit requirements. To comply 
with state and federal policy that no net loss of wetlands occurs, discharge into wetlands 
must be avoided and minimized to the extent practicable. For unavoidable impacts, 
compensatory mitigation is required to replace the loss of wetlands. 

No USACE permit will be effective in the absence of state water quality certification, 
pursuant to Section 401 of the Clean Water Act. The State Water Resources Control Board 
(SWRCB] is the state agency (together with the Regional Water Quality Control Boards 
[RWQCBs]] charged with implementing water quality certification in California. 

Project Applicability. SCVWD will apply for a Section 404 permit for the SMP Update. Any 
work within waters of the U.S. (i.e., wetlands and other waters], including relatively large 
waterways, small perennial and intermittent drainages, and wetlands maymay require a 
Section 404 fill discharge permit from the USACE and Section 401 Water Quality 
Certification from the RWQCB. Tidal salt marsh, tidal brackish marsh, most freshwater 
wetlands, and open water habitats (as described above] generally are considered waters of 
the U.S., subject to the jurisdiction of the USACE and RWQCB. As discussed above, the canals 
subject to SMP Update activities are not expected to be considered waters of the U.S.; 
however, this determination will be made by the USACE. 

Rivers and Harbors Act 

Section 10 of the Rivers and Harbors Act (1899] 33 U.S. Code (USC] 403 regulates the 
construction of structures, placement of fill, and introduction of other potential obstructions 
to navigation in navigable waters. Under Section 10 of the Act, the building of any wharfs, 
piers, jetties, and other structures is prohibited without congressional approval, and 
excavation or fill within navigable or tidal waters requires the approval of the chief of 
engineers. 

The USACE has the authority to issue permits for the discharge of refuse into, or affecting, 
navigable waters under section 13 of the 1899 Act (33 USC 407; 30 Statute 1152], The Act 
was modified by Title IV of Public Law 92-500, October 18, 1972; the federal Water 
Pollution Control Act Amendments of 1972 (33 USC 1341-1345; 86 Statute 877], as 
amended, established the National Pollutant Discharge Elimination System (NPDES] 
permits. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-6 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Project Applicability. Any maintenance activities conducted within or over the tidally 
influenced portions of Guadalupe, Coyote, and Alviso sloughs and the lower reaches of 
Permanente, Stevens, San Tomas Aquino, Calabazas, San Francisquito, Coyote, and Lower 
Penitencia creeks, Sunnyvale East and West Channels, and Guadalupe River, potentially 
could require a Section 10 Letter of Permission. 

Federal Endangered Species Act 

The federal Endangered Species Act (FESA] identifies species at risk of extinction and 
protects them and their habitats from unauthorized take. Take is broadly defined as to 
harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, collect, or attempt to engage in 
any such conduct. Take also can include habitat modification or degradation that directly 
results in death or injury of a listed wildlife species. An activity can be defined as "take” 
even if it is unintentional or accidental. Listed plant species are legally protected from take 
under the FESA only if they occur on federal lands or if the project requires a federal action, 
such as a Clean Water Act Section 404 fill permit from the USACE. 

The USFWS has jurisdiction over federally listed threatened and endangered plants, 
wildlife, and freshwater fish species under FESA, while the National Marine Fisheries 
Service (NMFS] has jurisdiction over federally listed, threatened, and endangered marine 
and anadromous fish. Authorized take can be obtained through Section 7 and/or Section 10 
of the ESA. Federal agencies, such as the USACE, are required to consult with the USFWS or 
NMFS if their actions "may affect" a listed species. The USFWS and/or NMFS may issue an 
incidental take statement and Biological Opinion (BO] before the federal consulting agency 
issues a permit. The federal consulting agency then incorporates the incidental take 
statement and BO into any authorization or permits. Alternatively, in the absence of federal 
involvement, incidental take can be authorized through the development and 
implementation of a Habitat Conservation Plan. 

Project Applicability. FESA compliance for the SMP Update will be achieved through 
Section 7 consultation implemented by the USACE, which will issue a Section 404 permit for 
the SMP Update (see above]. Proposed Project maintenance activities maymay affect a 
number of federally listed species. Federally listed fish and wildlife species that occur, or 
could potentially occur, in the Project Area include the Bay checkerspot butterfly 
{Euphydryas editha bayensis ], southern green sturgeon ( Acipenser medirostris ], Central 
California Coast steelhead ( Oncorhynchus mykiss), South-Central California Coast steelhead, 
California tiger salamander ( Ambystoma californiense), California red-legged frog, California 
condor [Gymnogyps californianus), California least tern ( Sterna antillarum browni ], least 
Bell’s vireo, California clapper rail, western snowy plover, salt marsh harvest mouse 
[Reithrodontomys raviventris), and San Joaquin kit fox ( Vulpes macrotis mutica). Federally 
listed plant species known to occur (or that have occurred historically] in the Project Area 
are the federally endangered Santa Clara Valley dudleya ( Dudleya setchellii), Tiburon 
paintbrush ( Castilleja affinis ssp. neglecta), Coyote ceanothus [Ceanothus ferrisiae), robust 
spineflower ( Chorizanthe robusta var. robusta), Contra Costa goldfields ( Lasthenia 
conjugens), and Metcalf Canyon jewel-flower {Streptanthus albidus ssp. albidus). Section 7 
Consultation between the USACE, USFWS, and NMFS would be required to authorize 
incidental take of listed species. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-7 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Magnuson-Stevens Fishery Conservation and Management Act 

The Magnuson-Stevens Fishery Conservation and Management Act governs all fishery 
management activities that occur in federal waters within the United States' 200-nautical- 
mile limit. The Act establishes eight Regional Fishery Management Councils responsible for 
the preparation of fishery management plans to achieve the optimum yield from U.S. 
fisheries in their regions. These councils, with assistance from the NMFS, establish essential 
fish habitat (EFH] in fishery management plans for all managed species. Federal agencies 
that fund, permit, or implement activities that may adversely affect EFH are required to 
consult with the NMFS regarding potential adverse effects of their actions on EFH, and 
respond in writing to recommendations by the NMFS. 

Project Applicability. Proposed Project maintenance activities in tidal waters and in 
Coyote Creek maymay affect EFH. The only fish species subject to a fisheries management 
plan that occurs in the Project Area with any regularity is the Chinook salmon 
[Oncorhynchus tshawytscha ], which is regulated by the Pacific Fishery Management 
Council’s Salmon Fishery Management Plan. Both Coyote Creek and the San Francisco Bay 
are officially listed as EFH for this species (Pacific Fishery Management Council 1999], and 
Chinook salmon also occur in Los Gatos Creek and the Guadalupe River. Although the 
Chinook salmon in the Project Area have been recognized as strays from hatchery releases 
(NMFS 1999, Hedgecock 2002], NMFS still considers habitat used by Chinook salmon in the 
South Bay as EFH. 

A number of fish species regulated by the Coastal Pelagics and Pacific Groundfish Fisheries 
Management Plans, such as the leopard shark [Triakis semifasciata), English sole [Parophrys 
vetulus), starry flounder ( Platichthys stellatus ], and big skate [Raja binoculata), occur in the 
tidal habitats of South San Francisco Bay and occasionally disperse upstream into the 
reaches of Alviso Slough, Coyote Slough, San Francisquito Creek, San Tomas Aquino Creek, 
and other tidal creeks in the Project Area. Species such as the northern anchovy ( Engraulis 
mordax), Pacific sardine ( Sardinops sagax ), and jack mackerel ( Trachurus symmetricus ] also 
occur in the South Bay; these species are less likely to occur in the uppermost tidal reaches 
of sloughs where Proposed Project activities would occur, but small numbers could 
potentially occur there. Thus, the NMFS maymay consider these tidal waters to be EFH as 
well. 

Federal Migratory Bird Treaty Act 

The federal Migratory Bird Treaty Act (MBTA; 16 USC, Section 703, Supplement I, 1989] 
prohibits killing, possessing, or trading of migratory birds except in accordance with 
regulations prescribed by the Secretary of the Interior. The trustee agency that addresses 
issues related to the MBTA is the USFWS. Migratory birds protected under this law include 
most native birds (USFWS 2010a], This act encompasses whole birds, parts of birds, and 
bird nests and eggs. The MBTA protects active nests from destruction and nests, whether 
active or not, cannot be possessed. An active nest under the MBTA, as described by the 
Department of the Interior in its April 16, 2003 Migratory Bird Permit Memorandum, is one 
having eggs or young. Nest starts, before egg laying, are not protected from destruction. 

Project Applicability. Almost all native bird species occurring in the Project Area would be 
protected by the MBTA. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-8 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


State Plans, Policies, Regulations, and Laws 

Section 401 Water Quality Certification 

The RWQCB is responsible for protecting surface, ground, and coastal waters in its 
jurisdiction. It requires that a project proponent apply for and obtain a CWA Section 401 
Water Quality Certification for any project that requires a CWA Section 404 permit from the 
USACE. 

Project Applicability. As described under Clean Water Act above, any work within waters 
of the U.S. (i.e., wetlands and other waters], including relatively large waterways, small 
perennial and intermittent drainages, and wetlands, maymay require a Section 404 fill 
discharge permit from the USACE and Section 401 Water Quality Certification from the 
RWQCB. Tidal salt marsh, tidal brackish marsh, most freshwater wetlands, and open water 
habitats (as described above] generally are considered waters of the U.S., subject to the 
jurisdiction of the USACE and RWQCB. 

Porter-Cologne Water Quality Control Act 

The Porter-Cologne Water Quality Control Act (Porter-Cologne Act] protects water quality 
and waters of the state of California. Activities that result in the discharge of fill material 
into "State Waters" that are not otherwise under the jurisdiction of the USACE (e.g., 
"isolated" wetlands without an interstate commerce connection or significant nexus to 
navigable waters of the U.S.] may require issuance of a Waste Discharge Requirements 
(WDRs] permit by the RWQCB pursuant to the Porter-Cologne Act and in compliance with 
the California Wetlands Conservation Policy. 

The Porter-Cologne Act authorizes the RWQCB to issue permits to control pollution (i.e., 
WDRs and NPDES permits] in compliance with implementation of water quality standards 
as outlined in the region's Basin Plan and taking into consideration beneficial uses to be 
protected. These regulations limit impacts to aquatic and riparian habitats from a variety of 
water pollution sources. 

Project Applicability. Any maintenance activities that would impact waters of the U.S. 
and/or State would require 401 certification and/or a WDR permit from the RWQCB. 

McAteer-Petris Act 

The McAteer-Petris Act was enacted in 1965 to promote responsible planning and 
regulation of San Francisco Bay. This law created the San Francisco Bay Conservation and 
Development Commission (BCDC], which is responsible for enforcing the McAteer-Petris 
Act, requiring that "maximum feasible public access, consistent with a project be included 
as part of each project to be approved by the BCDC." BCDC jurisdiction in the San Francisco 
Bay Area extends over the Bay, up to mean high tide and to 5 feet above mean sea level in 
marshes; and over a 100-foot shoreline band inland from the line of mean high tide or the 
line 5 feet above mean sea level adjacent to marshes. The Commission also has certain 
waterway jurisdiction in the vicinity of the Project area, along Coyote Creek and the 
Guadalupe River. The Commission does not have 100-foot shoreline band jurisdiction 
adjacent to its certain waterway jurisdiction. The Commission also has salt pond 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-9 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


jurisdiction consisting of all areas diked off from the bay and used between August 1966 
and August 1969 for the solar evaporation of bay water in the course of salt production. 

Project Applicability. Any maintenance activities that are conducted within tidal waters of 
the South San Francisco Bay or areas determined to be within the Shoreline Band may 
require a permit from the BCDC. 

California Endangered Species Act 

The California Endangered Species Act (CESA] (Fish and Game Code of California, Chapter 
1.5, Sections 2050-2116] prohibits the take of any plant or animal listed or proposed for 
listing as rare (plants only], threatened, or endangered. In accordance with the CESA, the 
California Department of Fish and Game (CDFG] has jurisdiction over state-listed species. 
The CDFG regulates activities that may result in "take" of individuals listed under the Act 
(i.e., "hunt, pursue, catch, capture, or kill, or attempt to hunt, pursue, catch, capture, or kill"]. 
Habitat degradation or modification is not expressly included in the definition of "take" 
under the Fish and Game Code. The CDFG, however, has interpreted "take" to include the 
"killing of a member of a species which is the proximate result of habitat modification." 

Project Applicability. Maint e nanc e activiti e s may r e sult in th e tak e of a numb e r of stat e- 
list e d sp e ci e s. A CESA tak e p e rmit or oth e r form of authorization may b e r e quir e d for Stat e- 
list e d wildlif e sp e ci e s occurring (or pot e ntially occurring] in th e Proj e ct Ar e a. State-listed 
species potentially occurring in the Project Area include the longfin smelt ( Spirinchus 
thaleichthys), California tiger salamander, bank swallow ( Riparia riparia ], California condor, 
bald eagle ( Haliaeetus leucocephalus), Swainson's hawk ( Buteo swainsoni), California 
clapper rail, California black rail ( Laterallus jamaicensis coturniculus), California least tern, 
least Bell’s vireo, salt marsh harvest mouse, and San Joaquin kit fox. Th e only stat e- list e d 
plant sp e ci e s known to occur in th e Proj e ct Ar e a is th e stat e- thr e at e n e d Tiburon paintbrush. 
Of these, the California clapper rail, California black rail, California condor, bald eagle, and salt 
marsh harvest mouse are also listed as fully protected species; take of such species must be 
avoided. Maintenance activities may result in the take of other state-listed species, including the 
California tiger salamander and longfin smelt; a CESA Incidental Take Permit would be required 
for take of these species. 

Native Plant Protection Act 

The Native Plant Protection Act (California Fish and Game Code Sections 1900-1913] 
requires permits for collecting, transporting, or selling plant species designated rare, or 
endangered by the Fish and Game Commission. 

Project Applicability. The CNPS has developed a set of lists of native plants in California 
according to rarity. Plants on List 1A, List IB, and List 2 meet the definitions of Section 
1901, Chapter 10 (Native Plant Protection Act] or Sections 2060 and 2067 (California 
Endangered Species Act] of the California Department of Fish and Game Code (Section 
1900-1913] as rare or endangered species. These species were fully considered during 
CEQA review of the Proposed Project in the context of this document. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-10 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


California Environmental Quality Act 

The California Environmental Quality Act (CEQA] is a state law that requires state and local 
agencies, such as SCVWD, to document and consider the environmental implications of their 
actions and to refrain from approving projects with significant environmental effects if 
feasible alternatives or mitigation measures exist that can substantially lessen or avoid 
those effects. CEQA requires the full disclosure of the environmental effects of agency 
actions, such as approval of a general plan update or the projects covered by that plan, on 
resources such as air quality, water quality, cultural resources, and biological resources. The 
State Resources Agency-promulgated guidelines for implementing CEQA are known as the 
State CEQA Guidelines. 

CEQA and the State CEQA Guidelines provide guidance in evaluating impacts of projects to 
biological resources and determining which impacts will be significant. CEQA defines 
"significant effect on the environment" as "a substantial adverse change in the physical 
conditions which exist in the area affected by the proposed project." Under State CEQA 
Guidelines Section 15065, a project's effects on biotic resources are deemed significant 
where the project would: 

• substantially reduce the habitat of a fish or wildlife species; 

• cause a fish or wildlife population to drop below self-sustaining 
levels; 

• threaten to eliminate a plant or animal community; or 

• "substantially reduce the number or restrict the range of an 
endangered, rare or threatened species" 

In addition to the Section 15065 criteria that trigger mandatory findings of significance, 
Appendix G of the State CEQA Guidelines provides a checklist of other potential impacts to 
consider when analyzing the significance of project effects. For biological resources, these 
impacts include whether the project would: 

• have a substantial adverse effect, either directly or through 
habitat modifications, on any species identified as a candidate, 
sensitive, or special status species in local or regional plans, 
policies, or regulations, or by the California Department of Fish 
and Game or U.S. Fish and Wildlife Service; 

• have a substantial adverse effect on any riparian habitat or other 
sensitive natural community identified in local or regional plans, 
policies, regulations or by the California Department of Fish and 
Game or U.S. Fish and Wildlife Service; 

• have a substantial adverse effect on federally protected wetlands 
as defined by Section 404 of the Clean Water Act; 

• interfere substantially with the movement of any native resident 
or migratory fish or wildlife species or with established native 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-11 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


resident or migratory wildlife corridors, or impede the use of 
native wildlife nursery sites; 

• conflict with any local policies or ordinances protecting 
biological resources, such as a tree preservation policy or 
ordinance; or 

• conflict with the provisions of an adopted Habitat Conservation 
Plan, Natural Community Conservation Plan, or other approved 
local, regional, or state habitat conservation plan. 

Section 15380(b] of the State CEQA Guidelines provides that a species not listed as rare, 
threatened, or endangered under CESA or FESA (except insects that are considered pests] 
may be considered rare, threatened, or endangered if the species meet the stated 
definitions. This section deals with situations in which the USFWS or Fish and Game 
Commission have not acted to list a species as rare, threatened, or endangered but in which 
the species is locally or regionally rare. 

The CDFG has produced three lists (amphibians and reptiles, birds, and mammals] of 
"species of special concern" that serve as "watch lists". Species on these lists are of limited 
distribution or the extent of their habitats has been reduced substantially, such that threat 
to their populations may be imminent. Thus, their populations should be monitored. They 
may receive special attention during environmental review as potential rare species but do 
not have specific statutory protection. 

The CNPS, a non-governmental conservation organization, has developed lists of plant 
species of concern in California. Vascular plants included on these lists are defined as 
follows: 

List 1A Plants considered extinct 

List IB Plants rare, threatened, or endangered in California and elsewhere 

List 2 Plants rare, threatened, or endangered in California but more common 
elsewhere 

List 3 Plants about which more information is needed—review list 
List 4 Plants of limited distribution—watch list 
These CNPS listings are further described by the following threat code extensions: 

.1—seriously endangered in California 
.2—fairly endangered in California 
.3—not very endangered in California 

Although the CNPS is not a regulatory agency and plants appearing on List IB or List 2 are, 
in general, considered to meet CEQA's Section 15380 criteria, adverse effects to these 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-12 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


species may be considered significant. Impacts to plants that are listed by the CNPS on List 3 
or 4 also are considered during CEQA review, although because these species are typically 
not as rare as those on List IB or List 2, impacts to them are less frequently considered 
significant. 

Project Applicability. All impacts to biological resources, including species not formally 
listed as rare, threatened, or endangered by the USFWS and CDFG, were considered during 
CEQA review of the Proposed Project. The significance guidance discussed above was 
considered in the determination of significance criteria for the evaluation of the Proposed 
Project. 

California Fish and Game Code 

The California Fish and Game Code Section 1601-1603 requires a Streambed Alteration 
Agreement for the fill or removal of material within the bed and banks of a watercourse or 
waterbody and for the removal of riparian vegetation. 

Fish and Game Code Sections 3503, 3503.5, 3513, and 3800 (and other sections and 
subsections] protect native birds, including their nests and eggs, from all forms of take. 
Disturbance that causes nest abandonment and/or loss of reproductive effort is considered 
"take" by the CDFG. Non-game mammals are protected by Fish and Game Code Section 
4150, and Fully Protected Species are protected by Sections 3505, 3511, 4700, 5050, and 
5515. 

The CDFG also maintains the California Natural Diversity Database (CNDDB] and the 
California Wildlife Habitat Relationships [CWHR] System. The CNDDB consists of historical 
observations of special-status plants, wildlife, and natural communities. Because the CNDDB 
is limited to reported sightings, it is not a comprehensive list of species that may occur in a 
particular area. However, it is useful in refining the list of special-status species that have 
the potential to occur on a particular site. 

The CWHR is a comprehensive information system for terrestrial vertebrates and their 
habitats in California. It includes [1] a complete species list of California's terrestrial 
vertebrate species, [2] life history information and geographic range data on terrestrial 
species regularly occurring in California, [3] a standardized habitat classification scheme for 
California, and [4] a community-level matrix model associating the regularly occurring 
wildlife species with the standardized habitats. Under Section 1802 of the Fish and Game 
Code, the Department of Fish and Game is the trustee agency for fish and wildlife resources 
and shall review and comment on environmental documents. 

Project Applicability. SCVWD will apply for a Section 1602 Streambed Alteration 
Agreement for the SMP Update. Maintenance activities would occur within the jurisdiction 
of the CDFG and would require a Streambed Alteration Agreement with CDFG. Maintenance 
activities may be required to take measures to avoid impacts to native mammals and 
nesting birds. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-13 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


3.3.3 Environmental Setting 

Climate and Soils 

Santa Clara County has a Mediterranean climate characterized by mild, wet winters, and 
warm, dry summers. The county has unique natural biological communities, adapted to this 
precipitation regime. The unique natural communities and temperature regimes have 
resulted in endemic plant species that are adapted to long periods of drought and frequent 
fire events. Soil types ultimately play a large role in influencing distributions of habitats and 
wildlife. As detailed in Section 3.7, Hydrology and Geomorphology, soils vary considerably in 
the Project Area. Soils in and immediately surrounding San Francisco Bay tend to be fine- 
textured, clayey soils that were deposited by tidal events. Soils in the valley lowlands and 
farther inland are very deep, medium to fine-textured soils, ranging from poorly to 
excessively drained. Soils higher in the valley and in the foothills may be derived from 
sedimentary, basic igneous, or sometimes serpentine, rock with clayey, loamy textured soils 
(USSCS 1968], 

Serpentine soils and bedrock support a unique assemblage of endemic plant and animal 
species in California. These soils form from weathered ultramafic rocks that provide 
relatively inhospitable conditions for plant growth, including: 1] a low calcium to 
magnesium ratio; 2] a lack of essential nutrients such as nitrogen, potassium, and 
phosphorus; and 3] high concentrations of heavy metals such as nickel and chromium that 
may be toxic to most plant species (Kruckeberg 1984], Plant species found on serpentine 
soils are adapted to or are able to tolerate these harsh soil conditions in areas where other 
plant species cannot grow as easily. Therefore, many special-status plants are endemics that 
are restricted to the range of serpentine soils. Serpentine in the Project Area is present as 
exposed bedrock outcrops, serpentine-derived soils, alluvially deposited serpentine soils at 
the edge of the valley floor and foothills, or a combination of these. The major 
concentrations of serpentine soils have been mapped for the county by the USSCS (1968], 
These include Coyote Ridge and other smaller serpentine outcrops on the east side of 
Coyote Valley south to the San Martin area; areas on the west side of Coyote Valley from the 
Santa Teresa Hills south to San Martin; small outcrops near Lexington, Calero and Coyote 
reservoirs; and inclusions within the valley, such as Communications Hill and Tulare Hill. 

Existing Land Uses, Natural Communities, and Habitats 

The Santa Clara Valley, which is dominated by agricultural and developed land uses, runs 
the length of the Project Area and is ringed by rolling hills. Plant communities in the Diablo 
Range to the east include grasslands, chaparral, and oak savannah (County of Santa Clara 
2011b], Communities to the west in the Santa Cruz Mountains include rolling grasslands, 
oak woodlands, and mixed hardwood and evergreen forests (County of Santa Clara 2011b], 
The Baylands occupy the northern portion of the Project Area and consist mostly of former 
salt evaporation ponds and remnant marshes and wetlands. As the Project Area is so vast 
and contains some terrestrial communities and habitats that may not be subject to 
disturbance by the SMP Update, for purposes of this document, only the communities and 
habitat types that have the potential of being directly affected by the Proposed Project or 
occur adjacent to work areas are described. Based on dominant plant species in the Project 
Area as determined using the AIS vegetation mapping described previously, the Proposed 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-14 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Project may affect the following natural communities/wildlife habitats: tidal salt marsh, 
tidal brackish marsh, freshwater wetlands (tidal and non-tidal], riparian forest and 
woodland, ruderal grasslands, serpentine grassland, serpentine seeps, serpentine rock 
outcrops, chaparral, oak woodland, and open water. The dominant and characteristic plant 
and animal species for each of these communities/habitats are described below, and a 
crosswalk between the vegetation units mapped by AIS and the natural 
communities/wildlife habitats described is provided in Table 3.3-4. Scientific names for 
plant species follow the nomenclature used in The Jepson Manual Higher Plants of California 
(Hickman 1993], An updated, second edition of The Jepson Manual is expected to be 
published in the later part of 2011. Appendix F provides a taxonomic crosswalk transcribing 
the species' scientific names from the 1993 edition of The Jepson Manual to the unpublished 
second edition that is provided on the Jepson Herbarium Web site (The Jepson Herbarium 
2011, Baldwin et al. 2011], Figure 3.3-1 depicts an example of the vegetation mapping data 
prepared by AIS and used for the current analysis; inclusion of maps depicting vegetation¬ 
mapping units throughout the entire Project Area at a scale that allows interpretation in this 
document is infeasible because of the extent of the Project Area and the fine scale of the 
mapping units. In addition to the natural communities discussed below, the Proposed 
Project also may impact small areas of developed habitat (including roads] and non-native 
trees. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-15 


December 2011 
Project No. 10.005 



Table 3.3-4. Crosswalk between Natural Community/Wildlife Habitat Types and Vegetation 
Mapping Units 


Natural Community/ 
Wildlife Habitat 

Vegetation Mapping Units 

Tidal Salt Marsh 

Cordgrass 

Salicornia 

Salicornia - Salt Grass - Jaumea 

Tidal Brackish Marsh 

Bulrush - Cattail 

Lepidium latifolium 

Fresh or brackish bulrush spp. 

Freshwater Wetlands 

Arid freshwater emergent marsh group 

Bulrush-cattail 

Typha 

Western North American freshwater aquatic vegetation group 
Eleocharis macrostachya, Downingia, Trifolium variegatum, 

Eryngium 

Freshwater wet meadow 

Riparian Forests and Woodlands 

Salix exigua 

Salix laevigata 

Toxicodendron diversilobum 

Sambucus nigra 

Rubus discolor 

Acer macrophyllum 

Acer negundo 

Agriculture group 

Aesculus californica 

Arundo donax 

Alnus rhombifolia 

Populus fremontii 

Riparian Forests and Woodlands 

Quercus agrifolia 

cont. 

Quercus lobata 

Juglans hindsii 

Umbellularia californica 

Southwestern North American riparian evergreen and deciduous 
woodlands group 

Baccharis salicifolia 

Eucalyptus 

Southwestern North American riparian/wash scrub group 

Platanus racemosa 

Ruderal/Non-native Grasslands 

Mediterranean California naturalized annual and perennial 
grassland group 

Baccharis pilularis 

California perennial and annual grasslands group 

Conium-Foeniculum patches 

Cliffs and rock outcropping 

Serpentine 

Serpentine component mapping unit 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-16 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Table 3.3-4. Crosswalk between Natural Community/Wildlife Habitat Types and Vegetation 
Mapping Units 


Natural Community/ 
Wildlife Habitat 

Vegetation Mapping Units 

Chaparral and Coastal Scrub 

Adenostomafasciculatum 

Arctostaphylos glauca 

California xeric chaparral group 

Oak Woodland 

Quercus agrifolia 

Quercus douglasii 

Quercus lobata 

Open Water 

Reservoirs 

Water group 

Small earthen dam ponds and natural lakes 

River and lacustrine flats and streambeds 

Perennial Stream Channel 

Concrete Lined Channels 

Earth Lined Channels 


Source: Mapped by AIS using units from Sawyer et al. 2009 


Land Use 

The northern half of Santa Clara County is extensively urbanized, by thirteen of the county's 
fifteen cities and 90 percent of its nearly 1.7 million residents (County of Santa Clara 
2011a], It is a major employment center, providing more than 25 percent of all jobs in the 
Bay Area (County of Santa Clara 2011b], The southern half of the county is mostly rural, 
with the exception of Gilroy, Morgan Hill, San Martin, and scattered low-density residential 
developments. It contains most of the county's agricultural land. In addition to livestock and 
poultry, agricultural land uses include approximately 231,000 acres of field crops (e.g., 
alfalfa, grain, pasture], bushberries, strawberries, floral crops, forest products, fruits and 
nuts, vegetable crops, seed crops, and nursery crops (e.g., bedding plants, ornamental trees 
and shrubs, Christmas trees] (Santa Clara County Department of Agriculture 2009], 

Tidal Salt Marsh 

Tidal salt marsh is located in the lower reaches of creeks surrounding the San Francisco Bay 
and is influenced by fluctuations in the tide and salinity. Salt marshes in the Bay typically 
consist of three zones: low marsh dominated by cordgrass ( Spartina spp.] occurring below 
the mean high water (MHW] mark; middle marsh dominated by pickleweed and occurring 
above MHW; and above this, a transitional high marsh zone with a mixture of pickleweed 
([Salicornia spp.] and other moderately halophytic species that can tolerate occasional high 
tides. Other halophytic plant species commonly found in salt marsh habitat located in the 
South Bay include alkali heath ( Frankenia salina), saltgrass ( Distichlis spicata), saltmarsh 
dodder [Cuscuta salina ], spearscale ( Atriplex triangularis), and marsh gumplant ( Grindelia 
stricta var. angustifolia). These species typically occur above the MHW mark in the middle 
marsh and less disturbed areas of the high transitional marsh zone. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-17 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


High marsh habitat often extends up levee banks in a disturbed ecotone that contains native 
marsh species as well as ruderal (disturbance-loving], non-native, salt-tolerant species such 
as iceplant ( Mesembryanthemum nodiflorum ), New Zealand spinach ( Tetragonia 
tetragonioides), Russian thistle ( Salsola soda), and Australian saltbush ( Atriplex 
semibaccata), as well as perennial pepperweed ( Lepidium latifolium). Differences in 
transitional, pickleweed, and cordgrass salt marsh habitat types affect wildlife use and 
sedimentation in the sloughs and channels draining into the Bay. 

Two species of cordgrass are found in the South Bay, the native Pacific cordgrass [Spartina 
foliosa) and smooth cordgrass (S. alterniflora), which is native to the east coast of North 
America. Smooth cordgrass easily hybridizes with Pacific cordgrass, which can quickly lead 
to widespread distribution of the hybridized species. Smooth cordgrass (and its hybrids] 
and perennial pepperweed are the predominant invasive plant species found in the tidal 
salt marshes in the Project Area. Such invasions not only affect the food web, but also grow 
lower into channels than the native cordgrass. This can result in the loss of channels to 
vegetation encroachment and subsequent sedimentation (PWA and H.T. Harvey & 
Associates 2006], as well as loss of mudflats that are valuable to wildlife and native 
estuarine aquatic organisms. The Bay-wide Invasive Spartina Program (ISP; funded by the 
California Coastal Conservancy] along with the District's Spartina Control Program (part of 
the 2002-2012 SMP FEIR mitigation package] has been successful at minimizing the extent 
of hybrid Spartina in South Bay marshes. Small populations of hybrid Spartina still exist in 
the South Bay, however, the ISP is continuing to monitor and control this plant Bay-wide 
with the ultimate goal of eradication. 

Tidal marshes in the Project Area are remnants of formerly much larger marshes. Tidal 
marshes support high densities of many wildlife species, including several species that are 
endemic to the San Francisco Bay. Based on trapping studies that have been conducted in a 
number of areas in the South Bay, the California vole ( Microtus californicus) is often the 
most common small mammal species found in these tidal marshes, but the state and 
federally endangered salt marsh harvest mouse has been recorded in pickleweed- 
dominated marshes such as New Chicago, Nine-Par Marsh, and the Coyote Creek Salt Marsh 
Harvest Mouse Management Area. The salt marsh wandering shrew ( Sorex vagrans 
halicoetes ] has been recorded in New Chicago Marsh and other areas as well. 

The state and federally endangered California clapper rail nests in cordgrass, dense stands 
of pickleweed, and marsh gumplant in tidal marsh habitats in the South Bay (e.g., Palo Alto 
Baylands, Alviso Slough, Guadalupe Slough, and Coyote Slough]; this species is found in the 
lower marsh zone where numerous small tidal channels are present. Alameda song 
sparrows ( Melospiza melodia pusillula) and Bryant's savannah sparrows ( Passerculus 
sandwichensis alaudinus ] also nest in tidal marshes. Alameda song sparrows prefer dense 
herbaceous vegetation wherever it occurs throughout the tidal marsh, while savannah 
sparrows nest in shorter vegetation such as pickleweed and high transitional marshes in 
upland ecotones. Other avian species that nest in tidal marshes in the South Bay include 
several species of ducks, herons, and egrets (Gill 1977]. California black rails winter in small 
numbers in tidal marshes in the South Bay. Shorebirds, swallows, blackbirds, and other 
avian species roost and forage, often in large numbers, in tidal marsh habitats in the South 
Bay, but most do not breed in these areas. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-18 


December 2011 
Project No. 10.005 







LEGEND 

Vegetation Type 

Areas of Little or No Vegetation 
Gaint Reed 
Coyote Brush 

Bulrush - Cattail mapping unit 

Eucalyptus 

Black Walnut 

Mediterranean California Naturalized Annual & Perennial Grassland 
Group (Weedy grasslands with no native component - Ruderal) 

Perennial Stream Channel 
Western Sycamore 
Fremont's Cottonwood 
Coast Live Oak 

River & Lacustrine Flats & Streambeds 
Roads > 50' wide 
Sandbar Willow 
Red Willow 

Southwestern North American Riparian Evergreen & Deciduous 
Woodlands Group 

' 



. 

^ - 


San 

Mateo 

County 



Santa Cruz County 



Project Area 
SMP Routes 

Miles 


DETAIL MAP 


' 

\ *** * 



1 

12 


San Joaquin 
County 


_ 


San Benito County 


L 


Imagery Source: Microsoft Virtual Earth 


. _. > v: -> - 


_* 


N 0 


300 600 Feet 


_ 


r 

V* -lGelbr 


\ M 






wS' 





A, 


A 


C*. •yw'^1 v 
' Y JWyifj# 

fe. ■ 





T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


_ *> __I 

Figure 3.3-1: Sample of Vegetation Mapping Performed for the SMP 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 
















































This page intentionally left blank. 



3.3 Biological Resources 


Tidal Brackish Marsh 

Tidal brackish marsh habitat occurs in the upper intertidal reaches of sloughs and creeks 
draining into the Bay, where vegetation is subject to tidal inundation diluted by freshwater 
flows from upstream. This habitat type is dominated by emergent, vascular plant species 
adapted to intermediate (brackish] soil water salinities and consists of brackish marsh 
species including short bulrushes such as alkali bulrush ( Scirpus rohustus] and saltmarsh 
bulrush ( Scirpus maritimus'). 

Wildlife communities are largely similar to those that occur in tidal salt marshes, with the 
potential for additional species to occur that prefer freshwater marshes. Marsh wrens 
(i Cistothorus palustris ), red-winged blackbirds ( Agelaius phoeniceus ], song sparrows 
(Melospiza melodia), and San Francisco common yellowthroats (Geothlypis trichas sinuosa ] 
are common breeders in brackish marshes. Salt marsh species, such as the federally 
endangered salt marsh harvest mouse and California clapper rail, occur rarely in the 
brackish marsh habitat. Many additional tidal salt marsh and freshwater marsh species may 
forage in these areas, including ducks, herons, egrets, sparrows, larger shorebirds, and 
swallows. 

Freshwater Wetlands 

Freshwater wetlands in the Project Area can be divided into two distinct biotic sub¬ 
communities. These are freshwater marsh and seasonal wetlands. Water availability and 
microhabitat conditions, such as shading and soils, can determine the composition of 
wetland species. In the Project Area, freshwater marsh communities tend to occur in 
relatively long, linear patches, such as those along the lower freshwater reaches of streams 
that feed into the Bay (e.g., Saratoga Creek, Calabazas Creek, Permanente Creek, Guadalupe 
River]; along Guadalupe Creek near the Los Capitancillos Percolation Ponds; and along 
Coyote Creek in the region of the Coyote Creek Park Chain. Seasonal wetlands in the Project 
Area typically occupy smaller, more discrete areas than freshwater marshes. They are found 
intermixed with freshwater marsh communities along Coyote Creek in the Coyote Creek 
Park Chain area and in the southern portion of the Project Area along Tar Creek, Tick Creek, 
and Uvas Creek. 

In many parts of the Project Area, freshwater wetlands have been disturbed or lost because 
of urban development or agriculture. For example, Grossinger et al. [2007] estimated that 
the area of freshwater marsh on the valley floor portion of the Coyote Creek watershed has 
declined by 85-91 percent since the late 1700s. 

Freshwater Marsh 

Freshwater marshes are present primarily where perennial or near-perennial inundation 
by shallow, fresh water occurs in an open (i.e., not wooded] environment. These marshes 
typically are densely vegetated and dominated by bulrush ( Scirpus spp.], rushes (Juncus 
spp.], sedges ( Cyperus spp.], bur reed {Sparganium spp.] and cattails ( Typha spp.]. Other 
common freshwater marsh herbs in Santa Clara County are native and non-native 
smartweeds ( Polygonum or Persicaria spp.] and primrose ( Ludwigia spp.]. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-19 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Freshwater marshes provide habitat for numerous bird species including ducks, gulls, terns, 
herons, egrets, and other waterbirds. The sora ( Porzana Carolina ] and Virginia rail ( Rallus 
limicola) forage in freshwater marshes in the Project Area during migration and in winter. 
American coots [Fulica americana), common moorhens ( Gallinula chloropus), pied-billed 
grebes ( Podilymbus podiceps), and several species of ducks breed in freshwater wetlands, 
channels, and ponds in and around emergent vegetation in the Project Area. Passerine 
species that breed in freshwater marshes include the marsh wren, song sparrow, common 
yellowthroat ( Geothlypis trichas], and red-winged blackbird. Amphibians such as the native 
Pacific chorus frog ( Pseudacris regilla ] and western toad ( Anaxyrus boreas), as well as the 
non-native American bullfrog ( Lithobates catesbeianus), also are present in this habitat. 
However, special-status amphibians such as the California tiger salamander and California 
red-legged frog are not known to breed in the small patches that have been mapped as 
freshwater marsh habitat in the Project Area, although they have been observed in 
freshwater marshes in the surrounding mountains. 

Seasonal Wetland 

Seasonal wetlands form during the rainy season, typically in topographic low areas with 
underlying confining soil layers (generally clays and silts] that prevent water from 
percolating into the ground. Seasonal wetlands also may form on areas with seasonally high 
groundwater tables. Dominant plant species include those noted above for the freshwater 
marsh, including rushes and sedges such as tall umbrella sedge [Cyperus eragrostis), but 
they are more commonly dominated by non-native annual hydrophytic species such as 
rabbitsfoot grass ( Polypogon monspeliensis ), hyssop loosestrife [Lythrum hyssopifolium), 
white sweetclover ( Melilotus albus), and bristly ox-tongue ( Picris echioides ]. 

Wildlife use of seasonal wetlands in the Project Area depends largely on the duration and 
depth of ponding, the extent of open water, and the structure and type of emergent 
vegetation. Most of the seasonal wetlands in the Project Area provide little open water, and 
they generally do not provide deep water. As a result, they are used primarily for winter 
and spring foraging by waterbirds, such as shorebirds, ducks, and geese. Song sparrows and 
red-winged blackbirds nest in vegetation in those seasonal wetlands that support taller, 
denser vegetation, and a variety of finches, sparrows, and other birds use this vegetation for 
cover and foraging habitat. Seasonal wetlands that provide standing water for at least 
several months support successful breeding by western toads and Pacific chorus frogs, 
while seasonal wetland swales that do not provide sufficient ponding provide only foraging 
habitat and moist refugia for these amphibians. In some areas, seasonal wetlands provide 
suitable breeding conditions for California tiger salamanders, if they hold water through 
May, and for California red-legged frogs, if they hold water into July. Common garter snakes 
[Thamnophis sirtalis ] and western terrestrial garter snakes ( Thamnophis elegans ] forage in 
these wetlands for amphibian larvae. 

Riparian Forests and Woodlands 

As a result of the long history of human disturbance, isolation, and other urban-associated 
pressures that began in the late 1700s, many riparian habitats in the Project Area have 
undergone a shift in composition. For example, Grossinger et al. [2007] documented a 
substantial shift in land cover along much of Coyote Creek, from relatively open sycamore 
alluvial woodland, riparian scrub, and unvegetated gravel bars to more dense and 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-20 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


homogeneous riparian forest. In addition, riparian forests and woodlands in the Project 
Area are predominately restricted to narrow corridors along streams, and many reaches of 
streams support little or no woody vegetation. In some areas, channels are lined with 
concrete, riprap, or gabions (e.g., Guadalupe River near Hillsdale Avenue], Although native 
trees dominate most riparian woodlands and forests in the Project Area, non-natives 
abound as well, and exotic species, such as eucalyptus ( Eucalyptus spp.], giant reed [Arundo 
donax), tree-of-heaven {Ailanthus altissima ), elms ( Ulmus spp.], and others occur frequently 
along these riparian systems. 

In some areas, riparian forests and woodlands have been protected, and in some cases 
restored (particularly along the larger streams such as Coyote Creek and the Guadalupe 
River], by SCVWD and others. Even though riparian land cover is limited, these habitats 
contribute a disproportionately high amount to landscape-level wildlife species diversity. 
The presence of water and abundant invertebrate fauna provide foraging opportunities for 
many species. The diverse habitat structure provides cover, nesting opportunities, and 
migratory corridors for many wildlife species in the region, supporting the most diverse 
bird communities in the Project Area (Rottenborn 1997]. 

Three major types of riparian forest and scrub communities occur in the Project Area: 
willow riparian forests, woodlands, and scrub; mixed riparian forest and woodland; and 
central California sycamore alluvial woodland (ICF Jones & Stokes 2010]. Central California 
sycamore alluvial woodland is considered a sensitive natural vegetation community by the 
CDFG [2007], 

Willow Riparian Forests. Woodlands, and Scrub 

Willow riparian forests, woodlands, and scrub comprise the most common riparian habitat 
type in the Project Area. These woodlands occur in the majority of drainages in the Santa 
Clara Valley. 

Willow species, such as the yellow willow ( Salix lucida ssp. lasiandra), red willow {Salix 
laevigata ], arroyo willow ( Salix lasiolepis), sandbar willow ( Salix exigua), and mulefat 
{Baccharis salicifolia) dominate willow riparian forests, woodlands, and scrub habitat in the 
Project Area. Most willow riparian habitat in the Project Area supports invasive trees such 
as black locust ( Robinia pseudoacacia ], holly oak ( Quercus ilex), eucalyptus, tree-of-heaven, 
and elms, as well as invasive herbaceous plants such as periwinkle ( Vinca major) and 
English ivy [Hedera helix) that dominate the understory. Other areas contain native 
understory species, such as California blackberry, poison oak ( Toxicodendron diversilobum), 
toyon ( Heteromeles arbutifolia), and Mexican elderberry ( Sambucus mexicana). 

Willow riparian habitats that include large, mature riparian trees occur along select 
portions of Coyote Creek and the Guadalupe River, with smaller areas dominated by mature 
trees present along other SMP-maintained streams as well. Dominant native canopy species 
in these areas include willows and Fremont cottonwood {Populus fremontii spp .fremontii), 
along with native understory species such as elderberry and wild rose ( Rosa californica). 

Dense, native willow riparian forests provide habitat for relatively high densities of native 
nesting songbirds, such as song sparrows, black-headed grosbeaks, and warbling vireos. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-21 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


This habitat also is more likely to support native bird and mammal species, such as 
Swainson's thrushes ( Catharus ustulatus ), yellow warblers, yellow-breasted chats ( Icteria 
virens), and San Francisco dusky-footed woodrats. 

The wider, more mature willow riparian corridors contain suitable foraging and breeding 
habitat for several functional groups of birds including insectivores (e.g., warblers, 
flycatchers], seed-eaters (e.g., finches], raptors, and cavity-nesters (e.g., swallows and 
woodpeckers]. Among the numerous species of birds that use the riparian habitats in the 
Project Area for breeding are the Pacific-slope flycatcher ( Empidonax difficilis), black¬ 
headed grosbeak [Pheucticus melanocephalus), warbling vireo ( Vireo gilvus), yellow warbler 
[Dendroica petechia ), belted kingfisher ( Ceryle alcyon), and black-chinned hummingbird 
(Archilochus alexandri ]. 

Several species of reptiles and amphibians occur in these riparian corridors in the Project 
Area. Leaf litter, downed tree branches, and fallen logs provide cover for the arboreal 
salamander ( Aneides lugubris), western toad, and Pacific chorus frog. Several lizards may 
also occur here, including the western fence lizard {Sceloporus occidentalis), western skink 
( Eumeces skiltonianus), and southern alligator lizard ( Elgaria multicarinata). Western pond 
turtles ( Actinemys marmorata ] and the non-native red-eared sliders ( Trachemys scripta) 
use riparian habitat, particularly for breeding and winter aestivation. Bats and small 
mammals, such as the ornate shrew ( Sorex ornatus), California vole, and Audubon's 
cottontail ( Sylvilagus auduhonii) use these riparian habitats as well. San Francisco dusky- 
footed woodrats ( Neotoma fuscipes annectens) occur, often at high densities, in riparian 
habitats in less developed areas, such as in Coyote Valley, but they are often absent from 
heavily urbanized streams. Medium-sized mammals, such as the raccoon ( Procyon lotor) 
and striped skunk ( Mephitis mephitis ], also are common in this habitat. Non-natives such as 
the opossum ( Didelphis virginiana), eastern fox squirrel ( Sciurus niger), Norway rat ( Rattus 
norvegicus), red fox ( Vulpes vulpes), and feral cat ( Felis catus ] may harass, compete with, or 
depredate eggs and young of native birds and small mammals, reducing the quality of this 
habitat for native riparian wildlife species. 

Mixed Riparian Forest and Woodland 

Mixed riparian forest and woodland habitat occurs in several drainages and persists in the 
foothills of the Project Area, along Thompson Creek, Uvas Creek, upstream reaches of 
Coyote Creek, Llagas Creek (above Chesbro Reservoir], Alamitos Creek, Calero Creek, and 
drainages east of Anderson Reservoir. White alder, big leaf maple, and western creek 
dogwood occur in lower densities in the Project Area. 

Mixed riparian forest and woodland habitat is composed of white alder ( Alnus rhombifolia), 
Fremont cottonwood, California sycamore ( Platanus racemosa), coast live oak ( Quercus 
agrifolia), valley oak ( Quercus lobata), California bay ( Umbellularia californica), and box 
elder ( Acer negundo). Understory trees and shrubs include willows ( Salix spp.], California 
buckeye ( Aesculus californica), native and introduced blackberry ( Rubus spp.], and poison 
oak. 

The structural diversity of mixed riparian forests in the Project Area supports high 
diversities of riparian-breeding species, and many of the same species found in willow 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-22 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


riparian forests also are present in mixed riparian habitats, but the lower vegetation volume 
of mixed riparian forests results in lower bird densities. Additional species that prefer low- 
density riparian habitats and higher structural diversity are likely to be present throughout 
this habitat type, including chestnut-backed chickadees ( Poecile rufescens), oak titmice 
[Baeolophus inornatus), bushtits (Psaltriparus minimus ), finches, black phoebes ( Sayornis 
nigricans ], western scrub-jays ( Aphelocoma californica], house wrens ( Troglodytes aedon), 
American robins ( Turdus migratorius), and dark-eyed juncos (Junco hyemalis). Raptors, such 
as red-shouldered hawks ( Buteo lineatus] and Cooper's hawks [Accipiter cooperii ], nest 
within these riparian corridors and forage in adjacent habitats. Oak, cottonwood, and 
sycamore trees also support cavity-nesting bird species such as woodpeckers, American 
kestrels [Falco sparverius ], barn owls [Tyto alba), and bat colonies. 

Central California Sycamore Alluvial Woodland 

Central California sycamore alluvial woodland, a CDFG sensitive natural vegetation 
community (CDFG 2007], occurs primarily in the upper watersheds above the Project Area, 
such as along Llagas, Uvas, Alamitos, Guadalupe and Stevens creeks, and the upstream 
reaches of Coyote and Upper Penitencia creeks. It occurs on broad valley floors along low, 
braided riparian channels. This land cover type usually forms only where floodplains are 
broad, along low gradient streams flowing over deep alluvial deposits. Sycamore alluvial 
woodland stands have an open canopy dominated by California sycamore, often 
interspersed with white alder and willows. Other associated species may include valley oak, 
coast live oak, and California bay. Winter flows typically scour the understory vegetation 
each season, and as such, herbaceous vegetation is spare and patchy. Riparian species such 
as willows, coyote brush ( Baccharis pilularis), mulefat, California buckeye, blackberry, 
Italian thistle ( Carduus pycnocephalus), poison oak, common chickweed ( Stellaria media), 
and bedstraw ( Galium aparine) may occur along the outer stream banks. 

Sycamore woodlands provide habitat for many species of bats, including the pallid bat 
( Antrozous pallidus), Brazilian free-tailed bat ( Tadarida brasiliensis), Yuma myotis, 
California myotis ( Myotis californicus), and big brown bat {Eptesicus fuscus). Cavity-nesting 
bird species, such as woodpeckers and American kestrels, are also likely to be found 
breeding in this habitat. Red-tailed hawks ( Buteo jamaicensis), red-shouldered hawks, 
great-horned owls ( Bubo virginianus), and other raptors nest in the larger trees in this 
habitat and forage in adjacent habitats. Species that prefer thick understory cover, such as 
towhees and sparrows, are less abundant in sycamore woodlands compared with other 
riparian habitats. 

Ruderal/Non-Native Grasslands 

California annual grassland habitat occurs commonly on undeveloped parcels and 
constructed levees throughout the Project Area. The largest expanses of this habitat are 
present on hills surrounding Coyote Valley, in the northern portion of the Santa Teresa Hills, 
to the east of Anderson Reservoir, and elsewhere along the hilly eastern margin of the 
Project Area. This habitat type also extends into Alviso, and along the valley floor on both 
sides of upper Coyote Creek north of the Morgan Hill city limits. 

Grassland communities are characterized by a dominance of grass and herb species, with 
less than 10 percent cover by trees and shrubs. Dominant plant species are non-native 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-23 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


annual grasses, such as ripgut brome ( Bromus diandrus), Italian ryegrass ( Lolium 
multiflorum), and wild oats (Avena sp.]. Associated species include many native and non¬ 
native forbs, such as California poppy ( Eschscholzia californica), lupine [Lupinus spp.], and 
fdaree ( Erodium spp.]. 

Native grassland habitat [non-serpentine] is distributed in small patches throughout 
portions of the California annual grassland habitat and typically includes a component of 
native purple needlegrass [ Nassella pulchra ] growing in association with wild oats and 
ripgut brome. It is relatively rare to find native grasslands dominated (i.e., greater than 50 
percent by relative percent cover] by purple needlegrass in the Santa Clara Valley. 

A small area of rock outcrops consisting of exposed non-serpentine bedrock occurs in the 
Project Area within California annual grassland habitat north of Alamitos Creek in the Santa 
Teresa Hills. These rock outcrops are devoid of soil and typically do not support vascular 
plants except within crevices that have accumulated soil. One exception is that several 
species of non-special-status dudleya [ Dudleya spp.] are able to grow in cracks and 
fractures of the outcrops. In addition, mosses and other epiphytes may grow in some 
crevices that can retain water for a short duration. 

Wildlife use of grasslands in much of the Project Area is limited by human disturbance, 
extent of the habitat in a specific area, abundance of non-native and invasive species, and 
isolation of grassland habitat remnants from more extensive grasslands. As a result, some of 
the wildlife species associated with extensive grasslands, such as grasshopper sparrows 
[Ammodramus savannarum), breeding Bryant's savannah sparrows, and western 
meadowlarks [ Sturnella neglecta) are absent from small patches of grassland within the 
urban matrix that occupies most of the Project Area. However, much of the grassland 
around the periphery of the Project Area is contiguous with larger expanses of grassy open 
space, and thus provides higher-quality habitat for grassland-associated wildlife species. 

California ground squirrels [ Spermophilus beecheyi), where they are present, are an 
important component of these grassland communities, providing a prey base for diurnal 
raptors and terrestrial predators. The burrows of California ground squirrels also provide 
refugia for several special-status wildlife species, such as the burrowing owl and the 
California tiger salamander. Other rodent species that are likely present in grassland 
habitats include the California vole, valley pocket gopher [ Thomomys bottae), and deer 
mouse [ Peromyscus maniculatus). Diurnal raptors such as red-tailed hawks, northern 
harriers [ Circus cyaneus), white-tailed kites [ Elanus leucurus), and American kestrels forage 
for these small mammals over grasslands during the day, and at night nocturnal raptors, 
such as barn owls, forage for nocturnal rodents, such as deer mice. Loggerhead shrikes 
[Lanius ludovicianus) forage in grassland habitats for insects and other prey. 

Open grassland habitat with bare ground is important foraging habitat for the pallid bat and 
Brazilian free-tailed bat. Mammals such as the coyote [ Canis latrans ], American badger 
[Taxidea taxus ], black-tailed jackrabbit [Lepus californicus), and striped skunk utilize 
grassland habitats in the Project Area for foraging. Reptiles such as western fence lizards, 
southern alligator lizards, western skinks, western terrestrial garter snakes, gopher snakes 
(. Pituophis catenifer), racers [ Coluber constrictor ], western rattlesnakes (C rota I us viridis ), 
and common kingsnakes [ Lampropeltis getula ] also frequent these habitats. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-24 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Serpentine 

Serpentine bunchgrass grasslands, rock outcrops/barrens, seeps, and chaparral are 
considered sensitive communities by virtue of their importance to special-status plants and 
animals and their relatively limited extent (CDFG 2007, ICF Jones & Stokes 2010], 

Serpentine Bunchgrass Grassland 

Serpentine bunchgrass communities have been documented in the Project Area primarily 
on either side of the Santa Clara Valley, from Coyote Ridge on the east and the Santa Teresa 
Hills on the west, south to the San Martin area. Smaller patches of serpentine grassland 
occur elsewhere, such as on Communications Hill, Tulare Hill, and north of Alum Rock in 
San Jose. 

Serpentine bunchgrass grasslands occur on soils derived from serpentine rock substrates. 
Most serpentine soils support a diverse grassland assemblage dominated by California 
dwarf plantain ( Plantago erecta), Italian ryegrass, and spring and summer wildflowers, 
including goldfields [Lasthenia spp.J, buttercup ( Ranunculus californicus ], purple owl’s 
clover ( Castilleja exserta), and tidy-tips [Layia platyglossa, L. chrysanthemoides), among 
many others. Native grasses, such as purple needlegrass, junegrass ( Koeleria macrantha), 
big squirreltail ( Elymus multisetus), creeping wildrye ( [Leymus triticoides), and other 
perennial bunchgrasses are common throughout this community. 

Serpentine grasslands are highly infertile because of their extremely high levels of 
magnesium, chromium, and nickel; low concentrations of nutrients such as calcium and 
nitrogen; and low water-holding capacity. A unique group of vascular plant species, which 
can tolerate the relatively high magnesium to calcium ratio, has evolved in response to 
these conditions. As a result, serpentine grasslands generally support native plant 
communities, including rare plants, such as the federally listed Santa Clara Valley dudleya 
and Metcalf Canyon jewel-flower, as well as most beautiful jewel-flower and smooth 
lessingia (see also Special-Status Plant Species below]. In turn, several invertebrate species, 
including the federally threatened Bay checkerspot butterfly, depend on serpentine 
grasslands because their host food plants are found primarily in these habitats. 

The Bay checkerspot butterfly occurs in native serpentine grassland communities that 
support dense stands of its primary larval food plant, dwarf plantain. Larvae also utilize 
secondary larval food plants such as owl's clover ( Orthocarpus spp.], and adult butterflies 
use nectar from plants such as goldfields, onion ( Allium spp.], tidy-tips, cream cups 
{Platystemon californicus ], and lomatium ( Lomatium spp.]. This species is associated 
primarily with large expanses of serpentine grassland, characterized by a diversity of slope 
exposures and moderate-to-high grazing intensity. 

Bird species that occur most abundantly in serpentine grassland habitats in the Project Area 
include the grasshopper sparrow, horned lark ( Eremophila alpestris), rufous-crowned 
sparrow ( Aimophila ruficeps ], and rock wren ( Salpinctes obsoletus). These species are well 
adapted to the patchy distribution of bunchgrass vegetation in serpentine habitats. 

Serpentine Rock Outcrops/Barrens 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-25 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Serpentine rock outcrops/barrens lack soil entirely and are typically devoid of vegetation, 
with visible rock outcrops usually covered in crustose (forming a crusty, fixed mass that 
covers the surface on which it grows] lichen species. Serpentine rock outcrops/barrens are 
found in a patchwork of low-growing serpentine plant communities in the grasslands on 
either side of Coyote Valley (including extensive areas on Coyote Ridge], Communications 
Hill, Tulare Hill, the Santa Teresa Hills, and in the San Vicente area west of Calero Reservoir 
and in the field south of Suncrest Avenue in the Alum Rock area, interspersed with intact, 
undisturbed patches of sagebrush chaparral communities. This habitat tends to exclude 
most special-status plant species as no soil accumulation exists in these areas; however, the 
federally endangered Santa Clara Valley dudleya occurs primarily in this habitat type. 
Crevices in these outcrops provide refugia for western fence lizards, common kingsnakes, 
and western rattlesnakes. Rock wrens hide their nests in these outcrops. 

Serpentine Seep 

Several serpentine seeps, small wetlands that typically lack woody vegetation and are fed 
by small springs or creeks supported by groundwater, occur in the Santa Teresa Hills and all 
along Coyote Ridge. These seeps are distinguished from other wetlands because they occur 
on serpentine soils within serpentine grassland habitat. Many of the serpentine seeps in the 
Project Area support the special-status Mt. Hamilton thistle ( Cirsium fontinale var. 
campylon)-, this is the only habitat type in which this species occurs. Serpentine seeps are 
wetland habitats that provide moist refugia for Pacific chorus frogs, western toads, and 
other amphibians, but typically do not pond water deep enough to provide suitable 
breeding habitat for these species. They also are so limited in extent that they are 
infrequently used by other aquatic/wetland-associated wildlife species, such as shorebirds 
or waterfowl. 

Mixed Serpentine Chaparral 

Mixed serpentine chaparral is an uncommon chaparral-type that is generally composed of 
chaparral species tolerant of a broad range of soil conditions such as those listed above, as 
well as species that are limited to serpentine soils such as leather oak ( Quercus durata), 
Coyote ceanothus, and chaparral silktassel ( Garrya congdonii). The dominant shrubs in 
mixed serpentine chaparral are often dwarfed and spaced more widely than is typically 
seen in non-serpentine stands (Holland and Keil 1995], Grass and herbaceous vegetation 
may or may not be present in the spaces between the shrubs. This unique community 
supports many special-status plants such as Coyote ceanothus, Santa Clara thornmint 
[Acanthomintha lanceolata ] and Sharsmith’s harebell ( Campanula sharsmithiae). Wildlife 
species typical of this community are similar to those described for chaparral and coastal 
scrub below. 

Chaparral and Coastal Scrub 

In the Project Area, chaparral and coastal scrub communities were mapped primarily in the 
area between Calero Reservoir and Almaden Quicksilver Park and along the Coyote Creek 
Park Chain. These are characterized by drought-tolerant, shrub-dominated landscapes that 
are exposed to intense sunlight. These habitat types form dense stands of shrubs with little 
understory and are prone to intense and regular fire cycles in natural settings. After a fire 
event, these habitat types recover quickly and support extraordinary blooms of annual 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-26 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


forbs adapted to fire during the first few years as the shrub canopy develops. Typical 
dominant species found in chaparral communities are chamise [Adenostoma fasciculatum), 
bigberry manzanita ( Arctostaphylos glauca), ceanothus ( Ceanothus spp.], and scrub oak 
[Quercus spp.]. Typical dominant species found in coastal scrub communities are black sage 
[Salvia mellifera), coyote brush, and California sagebrush [Artemisia californica). Coastal 
scrub communities generally occur on exposed sites with shallow, rocky soils. Overall, the 
shrub species comprising coastal scrub communities are lower in stature than chaparral 
and appear more open. In contrast, once the manzanita and ceanothus shrubs that dominate 
chaparral reach maturity these plants form a dense, impenetrable thicket of broad-leaved 
sclerophylous shrubs. 

Chaparral and coastal scrub habitats typically are dry and provide relatively low and 
homogeneous structure. In addition, the areas where these habitats occur in the Project 
Area are small and often surrounded by other habitat types, such as annual grassland and 
oak woodland. Therefore, wildlife utilization of these areas is largely determined by 
adjacent habitats. Nevertheless, a number of animal species occur in these habitats. 

Amphibians are usually absent or scarce in chaparral habitats because of their very dry 
conditions, and many other wildlife species occurring here either derive moisture directly 
from food or synthesize their water metabolically from seeds (e.g., the California pocket 
mouse [Chaetodipus calif amicus]]. Mammals that use chaparral and coastal scrub habitats 
for cover include the coyote, bobcat [Lynx rufus), and brush rabbit [Sylvilagus bachmani), 
among others. Nests of San Francisco dusky-footed woodrats often are present where oaks 
and/or poison oak are mixed with coyote brush scrub. California mice [Peromyscus 
californicus), which occupy woodrat nests, also are present. Bird species that nest in 
chaparral habitats include the California thrasher [Toxostoma redivivum), California towhee 
[Pipilo crissalis ), spotted towhee [Pipilo maculatus ), California quail [Callipepla californica ], 
wrentit [Chamaea fasciata ], loggerhead shrike, lesser goldfinch [Carduelis psaltria ], and 
Anna's hummingbird [Calypte anna). Rufous-crowned sparrows often nest where these 
habitats are dominated by California sagebrush. Reptiles that occur in these habitats include 
the gopher snake, western rattlesnake, southern alligator lizard, striped racer [Masticophis 
lateralis), California horned lizard [Phrynosoma coronatum frontale), and western fence 
lizard. 

Oak Woodland 

Oak woodland communities in the Project Area typically occur at elevations above 300 feet 
and are characterized by native California oaks (e.g., coast live oak, valley oak, and blue oak 
[Quercus douglasii ]]. Representative understory plants are weedy annual grasses, some 
native and introduced forbs, and occasional shrubs, such as toyon, poison oak, California 
coffeeberry [Rhamnus californica), and common snowberry [Symphoricarpos albus var. 
laevigatus). The special-status species big-scale balsamroot [Balsamorhiza macrolepis var. 
macrolepis) and robust monardella [Monardella villosa ssp. globosa) occur in oak woodland 
habitats. 

Many of the oak woodland habitats in the Project Area have been fragmented by urban and 
suburban land uses. Nevertheless, they still support a number of the common oak- 
associated wildlife species in the region. The western scrub-jay, acorn woodpecker 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-27 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


{Melanerpes formicivorus), oak titmouse, Nuttall’s woodpecker ( Picoides nuttallii), chestnut- 
backed chickadee, spotted towhee, and white-breasted nuthatch ( Sitta carolinensis) are 
year-round residents. Dusky-footed woodrats also are frequently found in oak woodlands. 
The deer mouse, California mouse, and the introduced eastern gray squirrel ( Sciurus 
carolinensis ] nest and forage in this habitat as well. Reptiles found in adjacent grassland and 
scrub habitats also occur regularly in oak woodland habitats. Bats, such as the pallid bat, 
may use hollows of larger, older oak trees for roosting in open-canopy oak woodland. The 
California myotis and long-eared myotis ( Myotis evotis ] may occur in areas of oak woodland 
with a closed canopy. 

Open Water 

Aquatic or open water habitats are permanently or semi-permanently flooded, and support 
less than 5 percent vegetation in emergent or submerged states. Isolated ponds, reservoirs, 
percolation ponds (off-stream groundwater recharge ponds], rivers, streams, canals, and 
ditches, and tidal/intertidal habitats represent the open water surfaces mapped in the 
Project Area. Such areas are described below in terms of the hydrologic regimes and the 
salinity of the water. 

Ponds and Reservoirs 

Very few naturally occurring ponds exist in the Project Area. Many human-made ponds, 
including old gravel excavation sites, stock ponds, or ornamental ponds associated with golf 
courses and parks, occur. Other water bodies in the Project Area include the Parkway Lakes, 
Lake Cunningham, Lake Almaden, and percolation ponds along Los Gatos, Llagas, Coyote, 
Upper Penitencia, Stevens, and Guadalupe creeks, the Guadalupe River, and Madrone 
Channel. 

There are 10 reservoirs in the Project Area: Anderson, Calero, Chesbro, Coyote, Guadalupe, 
Lexington, Stevens Creek, Uvas, Vasona, and Almaden. These reservoirs were built to 
provide water supply and storage uses for county residents. Reservoirs have altered 
downstream hydrology by reducing spring runoff events, dampening flood peaks and 
frequency, and supplying water to creeks that would normally be dry during summer 
months. They also retain sediment, preventing natural sediment dispersal throughout the 
watershed. Although no Proposed Project activities would occur in the reservoirs, these 
reservoirs influence the biological resources present in reaches both above and below them. 

Cormorants, gulls, and pelicans exhibit movements between foraging areas at inland 
reservoirs and the South Bay, and ospreys ( Pandion haliaetus), Forster's terns ( Sterna 
forsteri), and Caspian terns ( Sterna caspia ] forage for fish in a number of ponds and 
reservoirs in the Project Area. Since the late 1990s, small heron rookeries have become 
established on islands in inland reservoirs in the South Bay; these herons and egrets forage 
largely on fish in these waterbodies. 

Amphibian species that breed in ponds and reservoirs throughout the Project Area include 
the Pacific chorus frog, bullfrog, and western toad. Western pond turtles are known to occur 
in a number of creeks including Coyote Creek, Guadalupe River, Alamitos Creek; ponds on 
the Santa Teresa Golf Course; several SCVWD reservoirs (Almaden, Calero, Chesbro, 
Anderson, Uvas, Stevens Creek, Lexington, etc.]; and other small ponds throughout the 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-28 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Project Area (H. T. Harvey & Associates 1999a, CNDDB 2011], This species may occur in 
creek, pond, and reservoir habitats throughout the Project Area, though in urban areas, 
nesting habitat is limited or absent. Several non-native turtle species have been introduced 
into the Project Area as well. California tiger salamanders are known to breed in several 
ponds at the periphery of the Project Area, and near Communications Hill, where non¬ 
instream aestivation habitat is available and non-native aquatic predators, such as bullfrogs, 
green sunfish ( Lepomis cyanellus), mosquitofish ( Gambusia affinis), and Louisiana red 
crayfish [Procambarus clarkii), are absent. California red-legged frogs are known from 
ponds and streams in a few areas at the periphery of the Project Area; however, this species 
is largely absent from the portions of the Project Area on the Santa Clara Valley floor that 
have been heavily impacted by urban development and agricultural activities (H. T. Harvey 
& Associates 1997]. 

Common resident birds that occur in ponds, lakes, and reservoirs throughout the Project 
Area include the pied-billed grebe ( Podilymbus podiceps), double-crested cormorant 
[Phalacrocorax auritus), great egret, snowy egret [Egretta thula), Canada goose ( Branta 
canadensis ], mallard ( Anas platyrhynchos ], common merganser ( Mergus merganser ], 
American coot, and killdeer ( Charadrius vociferus), among others. Numerous species of 
wintering ducks, such as the northern shoveler [Anas clypeata), lesser scaup [Aythya 
affinis ], and bufflehead [Bucephala clangula ] occur in these habitats during fall and winter. 
Shorebirds, such as the greater yellowlegs [Tringa melanoleuca), spotted sandpiper [Actitis 
macularius), and others, forage and roost at the edges of these habitats during migration 
and winter. Additionally, a variety of mammals come to ponds and reservoirs to drink. 

The Coyote Creek Reach 1A pond along lower Coyote Creek was created and is managed 
specifically for waterbird use and provides habitat for numerous shorebirds, waterfowl, 
gulls, terns, and larger waders. Regular monitoring by the San Francisco Bay Bird 
Observatory of this 16-acre pond has recorded more than 57 species of waterbirds, the 
most common of which were dowitchers [Limnodromus spp.), American avocets 
[Recurvirostra americana), northern shovelers, and California gulls (Strong 2003], 
Additional birds using this pond include pectoral sandpipers [Calidris melanotos ], western 
sandpipers [Calidris mauri), and Wilson's phalaropes [Phalaropus lobatus), as well as large 
numbers of nesting American avocets, black-necked stilts [Himantopus mexicanus ], and 
ducks (Strong 2003], 

Creek and Stream Channels 

Creek and stream channels have been divided into three types for the purposes of the 
existing SMP: natural, mixed, and concrete. Natural channels are streams that have an 
unmodified bed and banks. Mixed channels have modified channels but have earthen 
stream-bottoms. The banks of mixed channels are often lined with excavated earth, rock 
rip-rap, gabions, concrete, or flood walls. Concrete-type channels are defined by concrete 
lining in the channel bed. Creek and stream channels may be vegetated with wetland 
vegetation, riparian vegetation, or open water, depending on the extent and type of 
modification applied. 

Amphibians such as the western toad, Pacific chorus frog, and the non-native bullfrog also 
are present in creeks and stream channels in the Project Area. The native western pond 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-29 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


turtle is present in low numbers in some reaches of these streams, as are several species of 
non-native turtles that have been released locally from captivity, such as red-eared sliders 
and painted turtles ( Chrysemys picta). Waterbirds, such as the mallard, green heron 
[Butorides virescens), great egret ( Ardea alba), and belted kingfisher, forage in these waters. 
Bats, including the Yuma myotis {Myotis yumanensis) and big brown bat, forage aerially on 
insects over these streams. 

A number of fish also use the creek and stream channels in the Project Area, including 
several species of native fishes. The rivers and creeks of Santa Clara County are home to 
12 native and 24 non-native species of fish (SCVWD 1995, Leidy 2007]. The most species- 
rich creek in terms of the number of fish species supported is Coyote Creek, with 12 native 
species (SCVWD 1995, Leidy 2007]. 

According to SCVWD fish sampling and relocation data [2002-2009] and Leidy [2007], the 
most common native fish in the Project Area streams draining to San Francisco Bay include 
the California roach ( Lavinia symmetricus), hitch ( Lavinia exilicauda), Sacramento sucker 
{Catostomus occidentalis), and threespine stickleback [Gasterosteus aculeatus), which occur 
in most watersheds and sub-watersheds in the Project Area. The federally threatened 
Central California Coast steelhead and the fall-run Chinook salmon are anadromous fish that 
spawn in several of these streams, such as Coyote Creek, Upper Penitencia Creek, the 
Guadalupe River, and Los Gatos Creek (SCVWD 2007a], The native Pacific lamprey 
{Lampetra tridentata) occurs in several streams in the Project Area. The creeks in the Pajaro 
River basin, which drain to Monterey Bay, support many of the same species as the creeks 
draining into San Francisco Bay. Dominant native fish species occurring in these creeks 
include species such as the Pacific lamprey, Monterey roach ( Lavinia symmetricus subditus), 
hitch, pikeminnow [Ptychocheilus grandis), threespine stickleback, and riffle sculpin ( Cottus 
gulosus ], as well as the South-Central California Coast steelhead (Smith 1982], 

A number of non-native fishes have been introduced to the Project Area, including the 
mosquitofish, largemouth bass ( Micropterus salmoides), bluegill ( Lepomis macrochirus), 
pumpkinseed ( Lepomis gibbosus), green sunfish, common carp ( Cyprinus carpio), goldfish 
( Carassius auratus), fathead minnow ( Pimephales promelas), bigscale logperch ( Percina 
macrolepida ), inland silverside ( Menidia beryllina), golden shiner ( Notemigonus 
crysoleucas), and threadfin shad ( Dorosoma petenense). Although fish in the Project Area's 
creeks consist of a mix of native and non-native species, most of the fish occurring in off- 
channel ponds and lakes are non-natives. 

Canals 

SCVWD-maintained canals (such as the Almaden Calero, Vasona, and Penitencia Canals] are 
used to divert water between streams or around certain stream reaches, or from one 
reservoir to another; canals also provide a flood protection benefit by intercepting hillside 
runoff. Some canals, such as the Coyote Alamitos Canal, Almaden Calero Canal, and portions 
of the Coyote Canal and Coyote Canal Extension, are concrete-lined and as a result support 
little riparian or wetland vegetation, other than vegetation that establishes on sediment that 
accumulates in the canals. As a result, dominant vegetation along these canals is determined 
primarily by the type of habitat (e.g., grassland or woodland] in which the canals have been 
constructed. Portions of the Coyote Canal and Coyote Canal Extension have natural earth 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-30 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


beds and banks, although little or no wetland or riparian vegetation (i.e., vegetation 
supported by groundwater associated with the canals] is present along these canals except 
where serpentine seeps drain into the canals. Among the canals in the Project Area, 
currently the Almaden Calero Canal, Vasona Canal, and Kirk and Page Distribution Systems 
are operable, whereas the Coyote, Coyote Extension, and Coyote Alamitos Canals are 
inoperable and are not used for water transfers or diversions, though these canals provide 
some flood protection benefit by intercepting runoff. 

Fish from upstream areas may occur in perennially wet sections of the canals, and 
amphibians such as Pacific chorus frogs and western toads use portions of these canals for 
refuge and as breeding habitat. Ducks such as mallards forage in canals in low numbers, but 
waterbird use of these facilities is generally low. 

Intertidal Areas 

Mudflat habitat occurs in intertidal areas from below mean lower low water to mean tide 
level. Such intertidal areas are expanses of unvegetated mud just beyond the lower edge of 
tidal wetlands and between the low-flow channel and edge of wetlands within the tidal 
reaches of slough and creek channels that drain to San Francisco Bay. Mudflats generally are 
covered by shallow water during high tide, and are exposed during low tides. These are 
dynamic depositional features, changing in extent and location depending on erosion and 
deposition of sediments. Narrow mudflats occur along the edges of the upper reaches of 
tidal sloughs while much more extensive flats are present at the mouths of the major 
sloughs. For example, a large expanse of newly formed mudflat habitat exists at the mouths 
of Alviso Slough and Guadalupe Slough, while small areas of mudflat are surrounded by 
freshwater marsh at the upper end of Coyote Slough. This habitat often supports less than 
10 percent cover of emergent vegetation, typically in the form of cordgrass and annual 
pickleweed (Salicornia europaea) that is too sparse to map as distinct salt marsh habitat. 

Aquatic intertidal habitat is present in the Project Area in the lower, tidal reaches of streams 
entering the Bay. Such areas have tidal estuarine influence and are too deep to support low 
tidal salt marsh and cordgrass species. Depending on tidal action, such areas can range from 
relatively clear to extremely turbid. These habitats are more benthic in nature than 
mudflats and are not exposed, even during very low tides. 

Detritus from tidal marshes, phytoplankton that settles in the water column, and algae and 
diatoms growing on the intertidal mudflats are responsible for the high productivity of 
benthic invertebrates on mudflats (Warwick and Price 1975, Life Science 2003], 
Crustaceans, polychaete worms, gastropod and bivalve mollusks, and other invertebrates 
live on or just below the surface of the mud. During the daily high tides, fish school over the 
mudflats to feed on these invertebrates. As the tide recedes and the flats emerge, the fish 
retreat to subtidal areas while considerable numbers of birds, primarily shorebirds, leave 
their high-tide roosts and feed on the flats. These mudflats are primarily responsible for the 
importance of the San Francisco Bay area to West Coast shorebird populations. Gulls and 
some dabbling ducks forage on the exposed mudflats as well. Because benthic invertebrates 
often recede deeper into the mud as the tidal elevation drops, especially large 
concentrations of foraging birds usually occur right at the edge of the receding or rising 
tideline. Although the largest numbers of shorebirds forage on the broad flats along the 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-31 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


edge of the Bay at low tide, some shorebirds, gulls, and large waders (e.g., herons and 
egrets] feed on the exposed flats along sloughs and channels, and the smaller channels in 
the brackish and salt marshes are the favored foraging areas for the state and federally 
endangered California clapper rail. Shorebirds, gulls, terns, American white pelicans 
{Pelecanus erythrorhynchos), and ducks often use exposed mudflats as roosting or loafing 
areas when they are available, as do Pacific harbor seals ( Phoca vitulina richardii). When the 
tides rise, most of these birds return to roosting areas in salt ponds or other alternate 
habitats. 

Invasive Species 

For over two centuries, people have brought non-native plants and animals into the Project 
Area, either accidentally (e.g., as stowaways in cargo shipments] or intentionally (e.g., 
imported for food, ornament, sport, or as pets], and many of these species have now been 
introduced into the wild. Such species that cause harm and, once established, spread quickly 
from their point of introduction are often called "invasive" species. 

Invasive species can threaten the diversity and abundance of native species through 
predation, competition for resources, transmission of disease, parasitism, and physical or 
chemical alteration of the habitat. Their effects on natural communities also may lead to 
direct effects on human activities, such as clogging waterways and water delivery systems, 
weakening flood protection structures, damaging crops, and diminishing sport fish 
populations (CDFG 2008c], 

As described previously, invasive plant species, such as smooth cordgrass, perennial 
pepperweed, and giant reed, are common in the Project Area. Introduced animal species are 
also common in the Project Area. A few of the more common introduced/invasive wildlife 
and fish species present, or with a high potential to be introduced, are discussed next. 

Mosquitofish have been introduced throughout the world, including Santa Clara County, to 
control mosquito populations. Such introductions have been shown to have negative effects 
on amphibians in experimental studies, including decreased survival of larval Pacific 
treefrogs (Goodsell and Kats 1999] and California newts (Gamradt and Kats 1996], as well 
as tail injury, reduced metamorph size, and altered activity patterns of larval California red- 
legged frogs (Lawler et al. 1999], 

New Zealand mud snails [Potamopyrgus antipodarum), which reproduce rapidly and can 
crowd out the native insects that aquatic wildlife depend on for survival, were first 
discovered in California in 2000 in the Owens River in Mono County (CDFG 2008d], In New 
Zealand, populations likely are kept in check naturally by a native parasite that is not 
present in North America. In the absence of such natural predators or parasites, population 
densities can reach nearly 1 million snails per square meter, and the species is 
parthenogenic (i.e., able to start a new population from only one snail] (CDFG 2008d], 
Biologists do not believe that the species can be eradicated once established (CDFG 2008d], 
Although this species has not yet been recorded in the Project Area, it has been located to 
the north in Alameda County on Alameda Creek and to the south in Santa Cruz County on 
the San Lorenzo River (Benson 2011], 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-32 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


The American bullfrog has been accidentally and intentionally introduced (e.g., for food in 
the 1920s by commercial frog farmers] throughout the world and is now established 
throughout most of the western United States, including the Project Area (California Herps 
2011], Their large size, mobility, generalized eating habits (their prey includes native 
amphibians as well as other aquatic and riparian vertebrates [Graber 1996]], and 
aggressive behavior have made bullfrogs extremely successful invaders and a threat to 
biodiversity (AmphibiaWeb 2008], 

Non-native species such as feral house cats ( Felis felis), red foxes, Norway rats, and 
muskrats are known to occur in the Project Area and are significant predators of native 
birds. For example, non-native Norway rats ( Rattus norvegicus) have long been known to be 
effective predators of clapper rail nests (DeGroot 1927, Harvey 1980, Foerster et al. 1990], 
and according to Harvey and Foerster et al., predators, especially rats, has accounted for 
clapper rail nest losses of 24 to 29 percent in certain South Bay marshes. 

Special-Status Plant and Animal Species 

CEQA requires assessment of the effects of a project on species that are "threatened, rare, or 
endangered"; such species are typically described as "special-status species." For planning 
purposes during the SMP Update and for assessment of impacts of the Proposed Project, 
special-status species have been defined as described below. Impacts to these species are 
regulated by some of the federal and state laws and ordinances described under Section 
3.3.2, Regulatory Setting. 

Special-Status Plants 

For the purposes of this document, "special-status" plants are considered plant species that 
are: 

1. Listed under the FESA as threatened, endangered, proposed 
threatened, proposed endangered, or a candidate species. 

2. Listed under the CESA as threatened, endangered, rare, or a 
candidate species. 

3. Listed by the CNPS as rare or endangered on List 1A, IB, or 2. 

4. Listed by the CNPS on List 3 or 4. 

For the purpose of this study, all special-status plants were analyzed for their potential to 
occur in the Project Area, and all those with the potential to occur were carried forward for 
additional analysis, except CNPS List 4 species were only carried forward if: 1] the only 
known populations occur in the vicinity of Santa Clara County; 2] it has been recorded by 
the CNPS (2011] as occurring in no more than two counties in California (i.e., very limited 
distribution]; 3] populations in the Project Area are at the periphery of the species' range or 
in areas where the taxon is especially uncommon or has sustained heavy losses; 4] the type 
locality occurs in the Project Area; or 5] populations exhibit unusual morphology or occur 
on unusual substrates. Two CNPS List 4 species meet the above criteria because of their 
restricted range: Santa Clara red ribbons ( Clarkia concinna ssp. automixa ] and Satan's 
goldenbush ( Isocoma menziesii var. diabolica ]. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-33 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Based on information from the CNPS and CNDDB (2011], a list of 94 special-status plants 
potentially occurring in Santa Clara County was compiled. After an analysis of documented 
habitat requirements and occurrence records for these species, 60 were determined to be 
absent from the Project Area. (A list of all species considered but rejected, and the reason 
for rejection is provided in Appendix G.] An additional two species were eliminated from 
consideration for species-specific reasons shown in Table 3.3-2424 located at the end of 
this section. The remaining 32 species are considered to occur potentially in the Project 
Area, based on their general habitat descriptions, also described in Table 3.3-2424 Detailed 
descriptions of each species potentially occurring in the Project Area and a discussion of 
known occurrences are provided in Appendix H and Table 3.3-24121. 

Special-Status Animals 

For purposes of this report, "special-status" animals are considered animal species that are: 

• listed under the FESA as threatened, endangered, proposed 
threatened, proposed endangered, or a candidate species; 

• listed under the CESA as threatened, endangered, or a candidate 
species; 

• designated by the CDFG as a California species of special 
concern; 

• listed in the California Fish and Game Code as a fully protected 
species (birds at Section 3511, mammals at Section 4700, 
reptiles and amphibians at Section 5050, and fish at Section 
5515]; 

• protected by the Marine Mammal Protection Act; 

• invertebrates that are on the CDFG's list of Special Animals 
(CDFG 2011] (although other taxa on that list are not included as 
special-status species in this analysis, if they do not meet one of 
the other criteria above, the invertebrates on the Special Animals 
list are considered special-status species here because no official 
list of invertebrate species of special concern exists]; or 

• Pacific lamprey, which could potentially be subject to listing 
under the state and/or federal Endangered Species Act during 
the period covered by this SMP update. 

The legal status and potential for occurrence of special-status animal species known to 
occur or potentially occurring in the general vicinity of the Project Area are shown in 
Table 3.3-24 22. located at the end of this section. Expanded descriptions are included in 
Appendix I for those species 1] known to occur in the Project Area, 2] for which potentially 
suitable habitat occurs within or in the general vicinity of the Project Area, 3] for which the 
site is accessible to animals from known populations, and/or 4] for which resource agencies 
and/or the Habitat Plan have expressed particular concern such that an expanded 
discussion is required. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-34 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Several special-status wildlife species that historically have occurred in the Project Area, or 
that have been recorded in Santa Clara County but not in the Project Area itself, are not 
expected to be present in the Project Area currently, at least not as special-status species. 
(Note: Several birds in this group are considered California species of special concern only 
when breeding [Shuford and Gardali 2008], Thus, if they occur in the Project Area only as 
non-breeders [e.g., as migrants or winter visitors], they are not special-status species when 
they occur in the Project Area.] They include the following: 

• The Central California Coast coho salmon (Oncorhynchus 
kisutch] was anecdotally reported to occur in Coyote Creek, and 
possibly in the Guadalupe River and Los Gatos Creek. However, it 
is unclear whether the species was ever actually present, as the 
life history of coho salmon is not conducive to its existence in 
South San Francisco Bay streams under either historical or 
current conditions. If it was ever present, it has been extirpated 
from these areas (Leidy et al. 2005, Spence et al. 2005], 

• The silvery legless lizard (Anniella pulchra pulchra] was 
historically recorded in the northern San Jose portion of the 
Project Area, but no recent records exist. This species has been 
displaced by development or disturbed by agriculture in much of 
the Project Area, and a suite of other factors (e.g., off-road vehicle 
activity, erosion, livestock grazing, and the introduction of exotic 
plant species] has altered remaining habitat to the extent that 
the species is unlikely to occur in the Project Area. 

• The willow flycatcher (Empidonax traillii] formerly nested 
commonly in riparian habitats on the Santa Clara Valley floor, 
but local populations were extirpated by the late 1960s. This 
species still occurs as an uncommon migrant in the Project Area, 
moving between wintering areas in Mexico and breeding areas 
to the north (Unitt 1987, Hunter et al. 2005], However, migrant 
willow flycatchers occurring in the Project Area are likely from 
breeding populations outside the state, and, thus, would not be 
individuals from the state-listed California population or the 
federally listed subspecies extimus that resides in riparian 
habitat of southern California (Unitt 1987], 

• Yellow-headed blackbirds (Xanthocephalus xanthocephalus] 
historically nested in marshes on the Santa Clara Valley floor, but 
breeding has not been noted anywhere in Santa Clara County 
since 1925 (Bousman 2007a], This species currently occurs in 
the Project Area in small numbers, but only during migration. 

Because it is only considered a California species of special 
concern when nesting, it is not a special-status species when it 
occurs as a non-breeder in the Project Area. 

Seven other bird species that are California species of special concern occur in the Project 
Area as non-breeding transients, foragers, or migrants, but they have never been recorded 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-35 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


breeding in or very close to the Project Area. These include the Barrow's goldeneye 
(Bucephala islandica), common loon ( Gavia immer), American white pelican, western least 
bittern ( Ixobrychus exilis hesperis), purple martin [Progne sub is), black swift [Cypseloides 
niger), and black tern ( Chlidonias niger). Because they are only considered species of special 
concern when nesting, they are not special-status species when they occur as non-breeding 
visitors to the Project Area. 

Several bird species that are state or federally listed and consequently special-status species 
year-round also occasionally occur in the Project Area as non-breeding migrants, transients, 
or foragers, but they are not known or expected to breed, to occur regularly, or to occur in 
large numbers in the Project Area. These include the California condor, Swainson's hawk, 
California black rail, California least tern, least Bell’s vireo, and bank swallow. These species 
are listed as threatened or endangered under the CESA and/or the FESA. Thus, they are 
considered special-status species even though they do not breed in the Project Area. 
Therefore, although these species occur in the Project Area only infrequently and/or in 
small numbers, they are discussed in further detail below. The willow flycatcher would be 
treated similarly to these species if the individuals that occur as migrants in the Project 
Area were from California breeding populations; however, because of the rarity of the 
species as a breeder in the state and the paucity of breeding pairs to the north of the Project 
Area, the probability that any California-breeding willow flycatchers migrate through the 
Project Area is extremely low. 

A number of other special-status animal species are addressed in greater detail below 
because they 1] are known to breed or could potentially breed in the Project Area, 2] occur 
fairly commonly as non-breeders in the Project Area (and thus could potentially be 
substantially affected by activities that occur under the Proposed Project], 3] are described 
in the Habitat Plan as potentially occurring in the Project Area, 4] and/or are of particular 
concern to regulatory agencies. These include the Bay checkerspot butterfly, Pacific 
lamprey, green sturgeon, Central Valley fall-run Chinook salmon, Central California coast 
steelhead, longfin smelt, California tiger salamander, California horned lizard, California 
red-legged frog, foothill yellow-legged frog ( Rana boylii), western pond turtle, black 
skimmer, California clapper rail, western snowy plover, northern harrier, white-tailed kite, 
golden eagle [Aquila chrysaetos ], bald eagle, American peregrine falcon [Falco peregrinus 
anatum), long-eared owl (As/o otus), burrowing owl, Vaux's swift ( Chaetura vauxi), olive¬ 
sided flycatcher ( Contopus cooperi), loggerhead shrike, yellow warbler, San Francisco 
common yellowthroat, yellow-breasted chat, Alameda song sparrow, grasshopper sparrow, 
Bryant's savannah sparrow, tricolored blackbird ( Agelaius tricolor), salt marsh wandering 
shrew, salt marsh harvest mouse, San Francisco dusky-footed woodrat, pallid bat, 
Townsend's big-eared bat ( Corynorhinus townsendii), western red bat ( Lasiurus blossevillii), 
ringtail ( Bassariscus astutus), San Joaquin kit fox, American badger, and Pacific harbor seal. 

Regulated and Sensitive Natural Communities 

Waters. Streams, Lakes, and Other Waters of the U.S./Waters of the State 

As described above under tidal salt marsh, tidal brackish marsh, freshwater wetlands, and 
open water, these habitats are extremely important in supporting numerous plant and 
wildlife species in the Project Area. Throughout California, the quality and quantity of 
aquatic and wetland habitat types has dramatically declined because of the construction of 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-36 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


dams, dikes, and levees as well as water diversions, the filling of aquatic and wetland 
habitat for development, and the overall degradation of general water quality caused by 
inputs of runoff from agricultural and urban development and other sources. As a result of 
their importance and the declines in these habitats that have occurred, aquatic and wetland 
habitat types are considered sensitive. 

As described in Section 3.3.2, Regulatory Setting, many streams, lakes, and wetlands in the 
Project Area are regulated by the USACE as "waters of the U.S." and/or by the RWQCB as 
"waters of the state". The BCDC regulates impacts to wetlands and other waters within 100 
feet of the BCDC-regulated shoreline band as well. 

Riparian Habitats Regulated Under California Fish and Game Code 

As discussed above, riparian plant and animal communities are extremely important to 
biodiversity and to the maintenance of biological and physical processes in the Project Area. 
However, these habitats have been degraded by a variety of factors, including the 
construction and operation of dams, realignment of streams and conversion to concrete- 
lined culverts, grazing and mowing, and population growth. In addition, historic 
groundwater overdraft has caused wetland and riparian loss throughout the region. 

As described in Section 3.3.2, Regulatory Setting, the California Fish and Game Code includes 
regulations governing the use of, or impacts to, many of the state's fish, wildlife, and 
sensitive habitats, including the bed and banks of rivers, lakes, and streams. 

Oak Woodlands 

Oak woodlands are considered one of California's most productive and important natural 
communities. They support a rich plant and wildlife community; at least 60 of California's 
169 terrestrial mammal species and approximately 60 species of birds are associated with 
oak woodlands (County of Santa Clara 2005], In addition, oaks play an important role in 
helping to maintain water quality in streams and rivers by reducing erosion. Yet more than 
a million acres of oak savannah and oak woodlands in California are estimated to have been 
lost since 1945 (County of Santa Clara 2005], Major factors contributing to the loss of oak 
woodlands include urban growth, conversion to agriculture, lack of regeneration of oak 
trees, and habitat fragmentation. As a result, numerous state and local agencies have 
established guidelines, regulations, and ordinances regarding the conservation of oak 
woodlands (e.g., Oak Woodlands Conservation Act [Fish and Game Code Section 1360- 
1372], Senate Bill 1334, and the Santa Clara County Oak Woodlands Management Plan 
[2005]]. 

CDFG Natural Communities of Special Concern 

CDFG natural communities of special concern are those that are of limited distribution 
statewide or within a county or region. These communities may or may not contain special- 
status species or their habitat. Most types of wetlands and riparian communities are 
considered special-status natural communities because of their limited distribution in 
California. CDFG natural communities of special concern mapped within the Project Area 
include Northern Coastal Salt Marsh, Serpentine Bunchgrass, and Sycamore Alluvial 
Woodland (CDFG 2007]. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-37 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Northern coastal salt marsh once occurred extensively in the tidally influenced lowlands 
surrounding San Francisco Bay. However, in the South Bay much of this habitat has been 
lost because of filling for development, landfills, and other uses; installation of flood 
protection structures which remove or mute tidal influence; and construction of levees to 
create managed ponds in areas that used to be extensive marshes. This community, which is 
located in tidal saline habitats at the extreme northern edge of the Project Area, supports a 
wide variety of plant and animal species specifically adapted to the dynamic hydrologic 
conditions and high salinity that occur within tidally influenced areas, including federally 
endangered species such as the salt marsh harvest mouse. 

As described previously, serpentine bunchgrass generally supports native plant 
communities including rare plants, such as the federally listed Santa Clara Valley dudleya 
and Metcalf Canyon jewel-flower as well as most beautiful jewel-flower and smooth 
lessingia. Several invertebrate species, including the federally threatened Bay checkerspot 
butterfly, depend on serpentine grasslands because their host food plants are found 
primarily in these habitats. Likewise, serpentine outcrops/barrens, serpentine chaparral, 
and serpentine seeps are considered sensitive communities (ICF Jones & Stokes 2010] 
because of their importance to serpentine-endemic plants and invertebrates and their 
limited regional distribution. In the Project Area, serpentine communities occur primarily 
on either side of the Santa Clara Valley, from Coyote Ridge on the east and the Santa Teresa 
Hills on the west, south to the San Martin area. Smaller patches of serpentine grassland 
occur elsewhere, such as on Communications Hill, Tulare Hill, and north of Alum Rock in 
San Jose. 

Central California sycamore alluvial woodland occurs along low, braided channels in areas 
with wide floodplains. The vegetation is dominated by California sycamore and the 
substrate tends to be cobbly or gravelly, scoured frequently by spring run-off events, and it 
supports a very sparse understory. Although sycamore alluvial woodlands were once more 
broadly distributed in California, they have experienced severe declines resulting from 
development of valley floors and changes in hydrology in suitable sites, typically caused by 
flood protection improvements along the drainages supporting sycamore stands. One study 
documented only 17 occurrences (comprising 2,032 acres] in the entire state (Keeler-Wolf 
et al. 1996], Sycamore alluvial woodland occurs sparsely in the Project Area, with the best 
examples of this community type occurring along Coyote Creek between U.S. Highway 101 
and the Ogier Ponds and along Pacheco Creek. 

3.3.4 Impact Analysis 

Methodology 

Impact Assessment. This impact analysis focused on potential effects of Proposed Project 
activities that may occur during 2012-2022. This evaluation does not assess the biological 
effects of the original construction of SCVWD's capital projects or prior [pre-2012] SMP 
activities. Rather, it evaluates the effects of proposed maintenance activities that are 
expected to occur over the next 10 years, compared to existing baseline conditions. 

In general, the primary adverse effects of Proposed Project activities would occur during 
maintenance activities and the period immediately following maintenance activities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-38 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Potential impacts are expected to include adverse effects on riparian, wetland, and instream 
habitats that would eventually restore themselves, impacts to associated plant communities 
and habitat of associated species, and potential degradation of water quality caused by 
herbicide use and releases of sediment. In some cases stream maintenance activities would 
result in long-term effects. Also, many shorter-term impacts would be repetitive, occurring 
a number of times during the 10-year period covered by the SMP Update. 

Several characteristics of the Project and Project Area complicate the quantification of 
impacts to biological resources that would occur during 2012-2022. First, a specific reach 
of creek or canal may be subject to several types of activities, either simultaneously or in 
succession. For example, a reach may undergo sediment removal one year, followed by 
herbicide application the next year. Vegetation management activities also may target only 
instream areas, only non-instream areas (such as levees], or some combination of instream, 
bank/bench, and levee areas. The different combinations of Proposed Project activities that 
may occur along a specific reach of creek or canal complicate the quantification of impacts. 

Further complicating the detailed quantification of impacts to biological resources in this 
analysis is the fact that maintenance activities may not occur exactly where they are 
projected. Experience from the 2002-2012 SMP indicates that some maintenance activities 
would be required in areas where they were not originally projected, and some reaches 
where activities were projected would not actually be subjected to maintenance. 
Furthermore, the total area in which SMP activities have occurred since 2002 has been 
substantially less than the projected impacts. Because of the impact avoidance and 
minimization that SCVWD employs through its BMPs, it is expected that actual impacts from 
2012-2022 Proposed Project activities would be less than projected. 

In addition, the projections for sediment removal and vegetation management activities do 
not specify precisely where within the projected reach maintenance activities would occur. 
Rather, these projections identify reaches of creek within which such activities are 
expected, as well as an estimated "work area percentage" indicating the percentage of that 
reach that would be affected by the specific activity. Because habitat conditions often vary 
within a reach, the precise effects of a specific activity within that reach can only be 
estimated at this time. The magnitude and location of impacts would be identified on an 
activity-by-activity basis as work was conducted, and the quantification those impacts 
would be refined and reported on an annual basis. 

Finally, there are some areas where work activities were projected in 2001 for the period 
2002-2012, and where activities are also projected for the period 2012-2022, but where 
the type and extent of activities may differ somewhat. For example, a reach subjected to 
manual vegetation management during the period 2002-2012 may undergo herbicide 
treatment during the period 2012-2022. In general, herbicide has less impact on vegetation 
than hand removal because hand r e moval herbicide application is targeted to specific 
individual plants. However, careful application of herbicide also is targeted and can reduce 
the effects on surrounding vegetation. Furthermore, hand removal makes it possible to 
remove larger diameter vegetation that fills a somewhat different ecological niche than 
herbicide application. To compound the difficulty of estimating the relative increase or 
decrease in the magnitude of the impacts resulting from these SMP Update activities, the 
projections in 2002 were based on linear extents and approximate widths while the 2012 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-39 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


projections were based on actually located polygons. Thus, a detailed comparison of the 
relative effects of these activities is infeasible. 

As a result of these constraints, the approach taken to evaluate impacts to biological 
resources in this analysis and the approaches to be followed by SCVWD as its maintenance 
proceeds during 2012-2022 are as follows: 

• This analysis describes qualitatively the types of impacts to 
biological resources that could occur as a result of 2012-2022 
Proposed Project activities. 

• This analysis broadly estimates the expected locations and 
potential magnitude of potential impacts, based on projections of 
sediment removal and vegetation management activities during 
2012-2022, and based on experience from the 2002-2012 SMP. 

While the extent of work that is performed would likely be lower 
than the projections, based on experience during 2002-2012, it 
is also possible that the extent of work will be higher than 
projected. Significance determinations were based on these 
projections and estimates, and the type of and need for 
compensatory mitigation has been determined accordingly. 

• Although the biological resources present in areas subject to SMP 
activities during the period 2002-2012 are often of lower quality 
than in areas where no recent maintenance has occurred, the 
discussion of the types of impacts that could result from 
proposed SMP activities during the period 2012-2022 applies to 
biological resources in all impact areas, regardless of whether or 
not work was performed in a given reach during the period 
2002-2012. For example, if a given reach underwent manual 
vegetation management during the period 2002-2012, but 
would undergo both manual and herbicide vegetation 
management during the period 2012-2022, the discussions of 
potential impacts from both manual and herbicide treatment 
provided below would apply to the 2012-2022 activities. 

However, if any type of vegetation management was previously 
projected in that reach during the period 2002-2012, and thus 
in-perpetuity mitigation was already provided for impacts to 
that reach, no additional mitigation would be required for 2012- 
2022 vegetation management activities even though such 
activities may differ from those performed during the prior 
decade. 

• During implementation of Proposed Project activities, SCVWD 
would refine the quantification of impacts to biological 
resources, such as the acreage of impacts to wetlands and 
riparian habitats, sensitive communities, or sensitive species' 
habitats. SCVWD would track these impacts annually, tallying the 
effects of Proposed Project activities for a specific year at the end 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-40 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


of the year. These refined impact calculations then would be 
used as the basis for determining mitigation that was to be 
provided at either that year's end or the following year. This 
annual mitigation analysis will clearly distinguish mitigation 
requirements for new work areas from areas where work was 
projected, and for which mitigation was already provided, during 
the period 2002-2012. Annual reports summarizing the impacts 
and associated mitigation needs would be submitted to the 
USFWS, NMFS, CDFG, USACE, and RWQCB. 

Potential impacts on biotic resources from the Proposed Project were systematically 
evaluated at both the project level and cumulatively. These impacts were first evaluated 
without considering implementation of BMPs to describe qualitatively how Proposed 
Project activities could impact biotic resources. Then, the impacts were evaluated with 
application of the program BMPs. For those impacts that remained potentially significant 
even with BMP implementation, feasible mitigation measures were identified, and the 
significance of the impacts were then re-evaluated to determine if compensatory mitigation 
would reduce impacts to a less-than-significant level. Impacts that remained significant with 
implementation of compensatory mitigation are described as significant and unavoidable. 

Biological resources would be affected not only by specific Proposed Project activities but 
also, in a few cases, by mitigation measures and BMPs. The net effect of these mitigation 
measures and BMPs would be beneficial. However, in a few cases, adverse effects may occur 
during implementation of these measures. For example, although relocation of steelhead 
and special-status reptiles and amphibians from work areas may be necessary to avoid 
mortality of those individuals, some injury or mortality may occur during relocation. As a 
result, the effects of the BMPs and the mitigation program also were analyzed where 
appropriate. 

Mitigation Assessment. Many of the areas where activities are projected for 2012-2022 
were similarly impacted during 2002-2012. In the impact assessments below, impacts that 
would be caused by continuing to conduct 2002-2012 maintenance activities over an 
additional period of 10 years (2012-2022] are distinguished from those caused by new 
activities, or activities in new areas where routine maintenance has not occurred in the past 
10 years. 

Compensatory mitigation, such as habitat restoration or preservation, has already been 
provided for impacts to areas where maintenance activities were projected for 2002-2012 
period. For the 2002-2012 SMP, impacts from projected sediment removal and vegetation 
management activities on instream wetlands and riparian vegetation were mitigated 
through an "up front" or defined mitigation package based on the maximum work 
projections estimated in 2001. However, the actual amount of maintenance work conducted 
during 2002-2012, and the associated impacts, have been less than projected. For example, 
to date the actual sediment removed (371,292 cubic yards] is only about 47 percent of the 
originally projected sediment removal volume of 795, 600 cubic yards. As a result, 
mitigation provided for the 2002-2012 SMP has exceeded, or will exceed once the 
mitigation has been completed, proposed 2002-2012 activities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-41 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Impacts from non-projected maintenance activities, such as bank stabilization activities, 
during 2002-2012 have been mitigated on an "as-needed" basis, using defined mitigation 
ratios as maintenance activities occurred. 

Because the 2002-2012 SMP will have mitigated potential impacts from projected sediment 
removal and vegetation management, whether they actually occurred or not, this analysis 
does not propose any additional compensatory mitigation for 2012-2022 activities that 
would occur in areas where previous maintenance activities were projected in 2002. The 
2012-2022 SMP Update identifies projected activities in channel reaches that were not 
previously identified or projected in 2002. These "new" work areas were not accounted in 
the 2002 SMP FEIR mitigation. After implementation of the SCVWD's BMPs, if residual 
impacts from maintenance activities in new work areas remained potentially significant, 
compensatory mitigation is prescribed that would reduce impacts to less-than-significant 
levels where feasible. This analysis describes the type(s] of compensatory mitigation that 
would be required and discusses how the amount of required mitigation would be 
determined. As described previously, SCVWD would refine the quantification of impacts and 
mitigation requirements on an annual basis, for annual review by resource agencies. 

The mitigation package, described in Appendix C, is designed to compensate for many of the 
residual impacts of the Proposed Project. The residual impacts associated with vegetation 
management and sediment removal activities would be temporary in nature—vegetation 
that was managed and wetlands and other waters affected by sediment removal would 
restore naturally if management were to cease. However, the repetitive nature of many SMP 
Update activities, which would not allow for regeneration of these resources if management 
occurred frequently, would result in longer-term effects. Permanent impacts associated 
with the SMP Update would occur with streambank stabilization activities when bank¬ 
hardening treatments were applied, as vegetation and habitats would not naturally restore 
themselves following the cessation of bank stabilization activities. As described in Appendix 
C, the mitigation for bank stabilization would occur on an as-needed basis. 

General Discussion of Impacts of Proposed Activities on Biological Resources 

The following sections describe generally how bank stabilization, sediment removal, 
vegetation management, and management of animal conflicts may impact different types of 
biological resources. These discussions are detailed here, rather than in the individual (e.g., 
species-specific] impact discussions that appear later in this document, to avoid 
redundancy. For example, the general discussions of how SMP Update activities may affect 
birds would apply to the more species-specific impact sections on the least Bell’s vireo, 
yellow warbler, yellow-breasted chat, burrowing owl, golden eagle, bald eagle, and other 
birds. Thus, the species-specific impact sections reference the general discussions included 
below, then go into more detail regarding species-specific impacts, as appropriate. 

Minor maintenance activities, which are described in Section 2.2.4, may occur throughout 
the Project Area, and 100-200 minor maintenance activities currently occur each year. Any 
minor maintenance activity typically would affect only a very limited area and, therefore, 
impacts to biological resources likewise typically would be limited in extent. Nevertheless, 
minor maintenance activities may have impacts similar to those that would result from 
bank stabilization, sediment removal, vegetation management, and management of animal 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-42 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


conflicts. Therefore, the discussions of how bank stabilization, sediment removal, vegetation 
management, and management of animal conflicts would affect biological resources pertain 
to similar minor maintenance activities, and the effects of minor maintenance activities on 
these resources would be tracked by SCVWD for mitigation purposes, just as would occur 
for the other activities. Minor maintenance also would include limited road repair and 
grading, which could occur at any location in the Project Area. 

Bank stabilization, sediment removal, vegetation management, management of animal 
conflicts, and minor maintenance could each occur, and some are projected to occur, along 
canals. Therefore, the effects of bank stabilization, sediment removal, vegetation 
management, and management of animal conflicts discussed below would apply to areas 
where those activities may occur along natural channels or canals. More detailed discussion 
of impacts from SMP Update activities along canals is provided where impacts to a certain 
biological resource are expected to occur disproportionately along canals. 

Determination of Impacts to Aquatic and Wetland Communities 

This section describes the general approach used to determine impacts on aquatic and 
wetland communities, including areas that are considered jurisdictional waters of the U.S. 
or waters of the state. 

Types of Impact 

Proposed Project activities may affect aquatic and wetland communities through direct or 
indirect disturbance of vegetation and disturbance, modification, or destruction of habitat. 
The types of potential impacts that were considered in this evaluation, grouped by 
maintenance activity type, are described below. 

Bank Stabilization 

Bank stabilization activities (e.g., grading to remove undercut banks and installation of bank 
armoring] and subsequent changes in hydrology may result in changes to the extent of 
wetland and aquatic communities present in a work site. Wetland vegetation may be lost as 
a result of mechanical or physical clearing in the work site (including access areas] and 
damage to vegetation may occur as a result of crushing by equipment; trampling by 
personnel; and compaction of soil, which could result in damage to plant roots. Some bank 
stabilization activities would require temporary water diversions or dewatering. This 
activity would result in the temporary loss of aquatic and wetland communities and may 
result in increased turbidity within and downstream from the footprint of the activities 
caused by mobilization of fine sediments. In addition, because barren slopes are more 
susceptible to erosion from incident rainfall, the loss of wetland vegetation and non¬ 
instream vegetation along stream banks following bank stabilization activities may result in 
an increase in erosion and sedimentation. Increased erosion and sedimentation may lead to 
the filling in of pools and damage to wetland vegetation. Bank stabilization also may affect 
downstream areas by altering flow patterns. 

Sediment Removal 

As sediment is removed, so is any vegetation that is growing on it, including freshwater and 
tidal wetland vegetation. Removal of wetland vegetation may result in the loss of 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-43 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


propagules for colonization of downstream areas. Additionally, similar to bank stabilization, 
some sediment removal activities would require temporary water diversions or dewatering. 
This activity would result in the temporary loss of aquatic and wetland communities and 
may result in increased turbidity caused by mobilization of fine sediments. Wetland 
vegetation also may be damaged by equipment accessing sediment removal sites. 

Vegetation Management 

In-channel vegetation management involves the foliar application of herbicide to targeted 
vegetation (e.g., plants with stems 2 inches diameter at breast height [dbh] or less] or the 
hand removal, mowing, or pruning of such vegetation (along with follow-up herbicide 
treatment of cut stumps]. Target vegetation primarily consists of herbaceous annual and 
perennial emergent wetland vegetation, such as cattails and bulrush, or woody vegetation 
consisting of native riparian species, such as willow and box elder, and non-native species, 
such as eucalyptus. "Limbing up," which entails removal of woody understory vegetation 
and the lower branches of taller trees, occurs along the slopes of levees that must be 
maintained to USACE-mandated standards. Vegetation management includes large woody 
debris relocation or removal, non-native invasive plant removal, and removal of trees up to 
12 inches dbh. Removal of trees larger than 12 inches dbh is not included in the SMP 
Update. Vegetation removal could result in increased scour caused by the loosening of 
sediment deposits, not only as a result of the removal of vegetation but also from 
accelerated flows. 

Management of Animal Conflicts 

Discharge of sediments into the channel as a result of ground-disturbing activities on levee 
surfaces (e.g., filling or compacting of crevices/holes] may result in the filling of pools as 
well as adverse effects on wetland vegetation. Regrading and recompacting the levee 
surface, as well as the installation of surface barriers, may require the removal of vegetation 
or may limit new vegetation growth caused by soil compaction and loss of accessible 
surface growing space. 

Quantification of Impacts 

Direct impacts on aquatic and wetland communities were evaluated by determining the 
quantity (e.g., in acreage or linear miles, as projections data was available] of projected 
sediment removal and vegetation management impacts to creek reaches potentially 
supporting these communities. 

Determination of Impacts to Non-Instream Sensitive Plant Communities 

This section describes the approach used to determine impacts on non-instream sensitive 
plant communities as defined under the Regulated and Sensitive Natural Communities 
discussion above. 

Types of Impact 

Proposed Project activities may affect non-instream sensitive plant communities through 
direct or indirect disturbance of vegetation and disturbance, modification, or destruction. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-44 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


The types of potential impacts that were considered in this evaluation, grouped by 
maintenance activity type, are described next. 

Bank Stabilization 

Bank stabilization activities may impact non-instream sensitive plant communities through 
temporary loss and degradation of the community (e.g., soft armoring of the bank, creation 
of temporary staging areas and access routes, alteration of hydrology on levee tops and 
upper side slopes through compaction, alteration of surface drainage patterns caused by 
movement of heavy equipment or soil disturbance, and introduction of non-native species] 
or permanent loss of the community (e.g., hard armoring of the bank]. Vegetation may be 
lost as a result of mechanical or physical clearing in the work site (including staging and 
access areas], and damage to vegetation may occur as a result of equipment use, trampling 
by personnel, and compaction of soil, which could result in damage to plant roots or stems. 
Such impacts may lead to the alteration of the communities' species composition, structure, 
and function. 

Furthermore, maintenance activities (including bank stabilization] often include the 
refueling of equipment on-site. Minor fuel and oil spills may occur during refueling, with a 
risk of larger releases. Without rapid containment and clean up, these materials may kill or 
impair the health of plants. 

Sediment Removal 

Because sediment removal would be limited to the stream channel, direct disturbance to 
upland plant communities would occur primarily through the establishment of staging and 
access areas in such communities. The concomitant operation of equipment in non¬ 
instream areas during sediment removal activities also may result in impacts to sensitive 
upland plant communities, similar to those described for bank stabilization activities. 

Vegetation Management 

The Proposed Project would include several methods of vegetation management activities, 
including mowing, hand removal, and herbicide application. Such activities may impact 
sensitive upland plant communities as a result of mechanical, physical, or chemical (i.e., 
herbicide] removal of vegetation, which could result in the alteration of the communities' 
species composition, structure, and function. In addition, the creation of temporary access 
routes and staging areas may result in direct impacts on sensitive upland plant communities 
caused by mechanical or physical removal of vegetation, crushing by equipment trampling 
by personnel, compaction of soil, and alteration of hydrology through compaction or 
alteration of surface drainage patterns resulting from movement of heavy equipment or soil 
disturbance. 

Management of Animal Conflicts 

Animal conflict management activities may impact sensitive upland plant communities as a 
result of the disturbance of the soil surface, collapsing and filling of burrows, installation of 
surface treatments to inhibit burrowing, and control of burrowing mammal populations 
that are a component of some sensitive upland communities, such as serpentine grasslands. 
Impacts may include direct removal or damage of vegetation; compaction of soil, which 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-45 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


could result in damage to plant roots; trampling by personnel; alteration of hydrology 
through compaction or alteration of surface drainage patterns; and exposure to toxic 
chemicals (e.g., petroleum products]. 

Quantification of Impacts 

Direct impacts on sensitive upland plant communities were evaluated by comparing the 
quantity and quality of communities present in the Project Area under baseline conditions 
to anticipated conditions after implementation of the proposed stream maintenance 
activities. For this evaluation, direct impacts on sensitive upland plant communities were 
assessed based on the potential for disturbance, degradation, or loss of communities as a 
result of projected activities. 

Determination of Impacts to Special-Status Plants 

The impact assessment for special-status plants was developed using general life history 
and habitat requirements. The impact analysis considered how each of the Proposed Project 
activities (i.e., sediment removal, vegetation management, bank protection, management of 
animal conflicts, minor maintenance, and canal maintenance] could affect each of the 
special-status plants identified as potentially occurring in the Project Area. The significance 
of impacts then was determined, based on the criteria discussed next. 

Types of Impact 

Proposed Project activities may affect special-status plants through direct or indirect 
disturbance of populations and disturbance, modification, or destruction of suitable habitat. 
The types of potential impacts that were considered in this evaluation, grouped by 
maintenance activity type, are described as follows. 

Bank Stabilization 

Bank stabilization activities may impact special-status plants through temporary loss and 
degradation of suitable habitat (e.g., soft armoring of the bank, creation of access routes, 
alteration of hydrology through soil compaction, alteration of surface drainage patterns 
resulting from movement of heavy equipment or soil disturbance; and introduction of non¬ 
native species] or permanent loss of habitat (e.g., hard armoring of the bank]. In addition, 
individual plants and populations may be lost as a result of mechanical or physical removal 
of vegetation in the work site (including staging and access areas], and damage to special- 
status plants may occur as a result of crushing by equipment; trampling by personnel; and 
compaction of soil, which could result in damage to plant roots. These activities could result 
in death, altered growth, or reduced seed set through physically breaking, crushing, wilting, 
or uprooting plants. 

Furthermore, maintenance activities (including bank stabilization] often include the 
refueling of equipment on location. Minor fuel and oil spills may occur during refueling, 
with a risk of larger releases. Without rapid containment and clean up, these materials may 
kill or impair the health of special-status plants. 

Sediment Removal 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-46 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


As sediment is removed, so is any vegetation that is growing on it, including special-status 
plant species. Because suitable habitat for only a single special-status plant species (Mt. 
Hamilton thistle] occurs within the stream channels, sediment removal is expected to result 
in the removal of few special-status plants. However, the operation of equipment in non¬ 
instream areas during sediment removal activities may result in damage to special-status 
plants by personnel and equipment; compaction of soil; alteration of hydrology through 
compaction or alteration of surface drainage patterns; removal of propagules for 
colonization of other areas; and exposure to toxic chemicals (e.g., petroleum products]. 

Vegetation Management 

Vegetation management activities may result in the alteration of habitat (including the 
introduction of non-native species] and/or direct damage and mortality of special-status 
plant individuals or populations as a result of mechanical or physical removal of vegetation 
or off target herbicide contact via drift. In addition, the creation of temporary access routes 
and staging areas may result in direct impacts on special-status plant species as a result of 
mechanical or physical removal of vegetation; trampling by personnel and equipment; 
compaction of soil caused by movement of heavy equipment or soil disturbance; removal of 
propagules for colonization of other areas; and exposure to toxic chemicals (e.g. petroleum 
products]. 

Management of Animal Conflicts 

Animal conflict management activities would include the destruction of rodent burrows on 
levees and slopes. Special-status plants may be directly impacted by burrow filling and 
compaction activities, which would involve disturbance of the soil surface, collapsing and 
filling of burrows, and subsequent soil compaction. Installation of surface treatments to 
inhibit burrowing by mammals also may affect special-status plants in the treated area, and 
control of populations of burrowing mammals may adversely affect the disturbance regimes 
of plant communities that support special-status plants. Impacts may include direct removal 
of vegetation to access and remove the burrows, compaction of soil, trampling by personnel, 
alteration of hydrology through compaction or alteration of surface drainage patterns, and 
exposure to toxic chemicals (e.g. petroleum products]. 

Quantification of Impacts 

For this evaluation, impacts on special-status plants were assessed based on the potential 
for the species or their habitat to be disturbed during stream maintenance activities. 
Impacts on special-status plants were evaluated by comparing the quantity and quality of 
habitat present in the Project Area under baseline conditions to anticipated conditions after 
implementation of Proposed Project maintenance activities, and by considering the 
potential for individual activities to affect known and potentially occurring populations of 
these species. 

Determination of Impacts to Wildlife and Fisheries 

The impact assessment for wildlife and fisheries was developed using general life history 
and habitat requirements for each of the five vertebrate classes (i.e., fish, amphibians, 
reptiles, birds, and mammals] and invertebrate groups (e.g., insects]. The impact analysis 
looked at each of the project components (i.e., sediment removal, vegetation management, 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-47 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


bank protection, management of animal conflicts, and minor maintenance], broken down by 
location and stream conditions, and evaluated how each of the major taxa would be affected 
by these work components. The significance of impacts then was determined based on the 
criteria discussed next. The following discussion applies to all fish and wildlife species and 
communities, including common and special-status species. 

Types of Impact 

Proposed Project activities may affect animals through direct or indirect disturbance of 
individuals and populations and disturbance, modification, or destruction of habitat. The 
types of potential impacts that were considered in this evaluation, grouped by maintenance 
activity type, are described next. 

Bank Stabilization 

Fish. The effects of bank stabilization on fish depend on the community supported in the 
reach where the activity occurs, the habitat present at the site, and the type of bank 
stabilization installed. Important habitat values for fish that may be affected by proposed 
bank stabilization activities would include effects on riparian shrubs and trees, instream 
and overhanging escape cover, and sedimentation. 

Riparian vegetation is important in determining the structure and function of instream 
habitat. For example, overhanging riparian vegetation provides shade that moderates 
stream temperatures. Unusual stream temperatures can lead to disease outbreaks and 
altered timing of migration (USDA Forest Service 1979], and excessive summer 
temperatures can be lethal to salmonids and their invertebrate prey species. Furthermore, 
terrestrial insects that occur in riparian vegetation are an important food item for 
salmonids, entering stream channels as a result of being blown or washed off riparian 
vegetation. In addition, plant material that falls into streams is an important food source for 
aquatic insects, which in turn are fed on by fish (USDA Forest Service 1979; Knight and 
Bottorff 1984], 

Repeated removal of smaller trees would prevent them from growing into larger trees, and 
thus over the long term, Proposed Project activities could reduce the input of large woody 
debris into streams and reduce the development of extensive root systems that would 
provide additional instream complexity. Over the course of the 10-year SMP Update (2012- 
2022], such impacts would be limited by the extent to which 10 years’ growth could 
substantially change habitat conditions or the contribution that individual trees could make 
to fish habitat. However, vegetation management would reduce the number of trees that 
grew tall enough to provide such habitat complexity resources to streams. Such complexity 
would be important to fish by encouraging the development of riffle/pool complexes, which 
would be important to steelhead spawning and feeding, and would provide refugia from 
predators and high flow velocities. Thus, bank stabilization activities that resulted in the 
loss of riparian vegetation (e.g., grading to remove undercut banks and clearing of 
vegetation before the installation of bank armoring] may adversely affect fish as a result of 
increased water temperatures and reduced food availability. The grading and armoring of 
undercut banks and the removal of overhanging vegetation and associated roots protruding 
from eroding banks also may adversely affect fish habitat by reducing the availability of 
instream escape cover. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-48 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Although the loss of organic matter associated with vegetation that was removed could 
affect the aquatic food web, a benefit would occur to thinning of vegetation in areas that 
were formerly densely shaded. The presence of dams along most SMP-maintained streams 
likely has resulted in significant shifts in vegetation type and density over time along the 
stream reaches below the dams. Without heavy flushing flows during winter storms, 
vegetation has encroached on the channel, reducing channel width and, in many areas, 
densely shading the channel. In Uvas Creek, a study by Casagrande (2010] found that 
steelhead grew much more quickly, and thus were much larger by their first winter, at less 
shaded, somewhat warmer sites, which had higher prey abundance, than at densely shaded, 
cooler sites. Casagrande [2010] verified that invertebrate biomass was considerably higher 
at less heavily shaded sites than under a dense forest canopy. His findings confirm those of 
other studies, demonstrating greater stream productivity (Murphy et al. 1981, Bilby and 
Bisson 1992, Quinn et al. 1997, Ambrose et al. 2004] and greater salmonid production 
(Wilzbach et al. 1986, 2005; Nislow and Lowe 2006] along reaches with lower canopy 
closure and higher light levels. Fish sampling by SCVWD in reaches below dense canopy has 
found very low densities of fish (of any species], apparently as a result of very low food 
densities (M. Moore, unpublished data]. Therefore, thinning of vegetation as a result of the 
SMP Update's vegetation management component may have considerable benefits to 
steelhead and other fish by increasing prey abundance in areas that are currently heavily 
shaded. 

The loss of riparian vegetation on channel banks following bank stabilization activities also 
may result in an increase in erosion and sedimentation. Stream bank erosion is a natural 
process that can be beneficial to fish by providing a source of the boulders, cobble, and 
gravel necessary for high quality salmonid spawning, rearing, and overwintering habitat. 
However, when natural levels of erosion are exceeded, sedimentation may have adverse 
effects on salmonid habitat by filling in spaces between gravels and cobbles. This 
embedding of gravels can impede intragravel flow, which is important for delivering oxygen 
to incubating eggs; create an impenetrable barrier that prevents the emergence of fry from 
their gravel nest; and decrease the amount of available habitat for overwintering steelhead, 
which use interstitial spaces in cobble or boulder substrate during winter periods of 
inactivity to reduce their exposure to predation and as refuge from downstream 
displacement during high velocity flows (Bustard and Narver 1975, Stillwater Sciences 
2006], Increases in turbidity and sediment input also may cause stress to fish because of 
feeding difficulties or displacement. Minor spills of petrochemicals, hydraulic fluids, and 
solvents may occur during vehicle and equipment refueling or as a result of leaks, adversely 
affecting water quality and potentially killing or injuring fish. Similarly, contact by uncured 
concrete with water could release chemicals that could impair the health of fish. 

In accordance with its BMPs, SCVWD would capture and relocate steelhead before the 
initiation of bank stabilization activities that would require temporary water diversions or 
dewatering. During relocation operations, steelhead would be subject to harassment, 
pursuit, capture, mortality, and related stresses associated with netting and electrofishing. 
In addition to direct injury and mortality, the effects of electrofishing may include reduced 
growth rates of injured fish for at least a year following the electrofishing event (Dalby et al. 
1996; Ainslie et al. 1998], Fish that were not relocated and that remained within the work 
site may be subjected to degraded water quality, temporary blockage of migration, 
stranding in isolated pools, and mortality as a result of maintenance activities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-49 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Soil and groundwater in the Guadalupe River watershed contain potentially hazardous 
levels of mercury contamination (see Section 3.6, Hazards and Hazardous Materials ). 
Maintenance activities involving ground disturbance, such as sediment removal and bank 
stabilization, may expose the mercury and potentially release it into the environment. 
Mercury is a toxic constituent that bioaccumulates in the food chain of aquatic organisms 
and terrestrial wildlife. Effects of methylmercury exposure on wildlife can include mortality, 
reduced fertility, slower growth and development and abnormal behavior that affects 
survival, depending on the level of exposure (Scheuhammer et al. 2007, USEPA 2010], 

Certain activities proposed under the SMP Update (e.g., bank stabilization and sediment 
removal] may require the construction of coffer dams to temporarily dewater the affected 
channel and minimize impacts on water quality. Coffer dams may be constructed of 
inflatable dams, sand bags, or possibly fiberglass sheet piles that could be pushed into place 
(rather than hammered into place]. 

Bank stabilization activities often necessitate the operation of heavy equipment within the 
stream bed fafter dewateringl. Movement of heavy equipment may compact the substrate, 
potentially killing benthic invertebrates fwhich may serve as prey for fish], embedding 
gravel within finer sediments, and otherwise altering habitat for fish and their prey. 

Amphibians and Reptiles. Potential direct effects on amphibians and reptiles as a result of 
bank stabilization activities could include injury or mortality of individuals by equipment, 
vehicle traffic, and worker foot traffic and disturbance of emergent vegetation, boulders, or 
cobbles that would support egg masses. In addition, because most reptiles and amphibians 
are oviparous (egg-laying], destruction of eggs/nests also could occur during maintenance 
activities. Furthermore, petrochemicals, hydraulic fluids, and solvents that were spilled or 
leaked from vehicles or equipment may kill individuals at any life stage, and increased 
sediment deposition may suffocate embryos and tadpoles. Special-status amphibians and 
reptiles that were found during pre-construction surveys and relocated to suitable habitat 
outside of the work site may be subjected to physiological stress and greater risk of 
predation. 

Fossorial (burrowing] species and species that use existing animal burrows as refugia (e.g., 
Pacific tree frogs, western toads, western fence lizards, California newts [Taricha torosa ], 
ensatina [Ensatina eschscholtzii], California tiger salamanders, California red-legged frogs, 
western skinks, gopher snakes] may be crushed in their burrows by the passage of heavy 
equipment or trapped and suffocated. Furthermore, loss of subterranean habitat (i.e., 
burrows] as a result of grading and bank armoring may result in the displacement of small 
mammals and invertebrates that would serve as a food source for some species of 
amphibians and reptiles. Additionally, where "hard” bank stabilization methods were used, 
bank protection could result in the loss of foraging, nesting, and overwintering habitat by 
precluding the re-establishment of riparian vegetation. 

Daily movements throughout their home range may be temporarily affected during 
maintenance activities as a result of dewatering or disturbance of non-instream habitat. 
Seasonal movements (i.e., breeding, aestivation] also may be affected, depending on the 
timing and duration of activities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-50 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Substrate vibrations or sounds may cause individuals to move out of refugia, exposing them 
to a greater risk of predation or desiccation, and may interfere with predator detection, 
causing a decrease in time spent foraging. Additionally, increases in human concentration 
and activity in the vicinity of suitable habitat may result in an increase in native and non¬ 
native predators that would be attracted to trash left in the work site. For example, 
raccoons, American crows (Corvus brachyrhynchos), and ravens (Corvus corax ] would be 
attracted to trash and also would prey opportunistically on amphibians. 

As discussed above, bank stabilization activities in the Guadalupe River watershed may 
expose soils contaminated with mercury. Effects of methylmercury exposure on wildlife 
could include mortality (death], reduced fertility, slower growth and development, and 
abnormal behavior that affects survival, depending on the level of exposure (Scheuhammer 
etal. 2007, USEPA 2010], 

Birds. Birds that foraged or roosted in the work site would be affected while heavy ground 
disturbance, noise, and vibration caused by the work activity proceeded. Individuals of 
these species (especially eggs or young in nests] could be killed or injured during 
maintenance activities by personnel or equipment. Maintenance activities causing a 
substantial increase in noise, movement of equipment, or human presence near active nests 
could result in the abandonment of nests, and possibly the loss of eggs or young as a result. 
In addition, increased human activity may affect the behavior of birds, causing them to 
avoid work sites and possibly exposing them to increased competition with other birds in 
the areas to which they dispersed and increased levels of predation caused by unfamiliarity 
with the new area. Increases in human concentration and activity associated with 
maintenance in the vicinity of suitable habitat also may result in an increase in native and 
non-native predators that would be attracted to trash left in the work site and a reduction in 
the quality of breeding or foraging habitat caused by the introduction of non-native 
vegetation. 

Clearing and grading may result in the temporary or permanent loss of breeding and/or 
foraging habitat. In addition, increased sedimentation or hazardous material spills from 
maintenance activities may result in the temporary or permanent degradation of water 
quality and, hence, habitat quality in marsh or aquatic habitats downstream from work sites 
and could impact aquatic and riparian bird species. 

As discussed above, bank stabilization activities in the Guadalupe River watershed may 
expose soils contaminated with mercury. Birds fed inorganic mercury show a reduction in 
food intake and consequent poor growth, with other reported effects including increased 
enzyme production, decreased cardiovascular function, blood parameter changes, immune 
response, changes in kidney function and structure, and behavioral changes] (Boening 
2000, Scheuhammer et al. 2007, USEPA 2010], 

Mammals. During bank stabilization activities, smaller mammals may be crushed or injured 
by personnel or equipment. Furthermore, species that seek safety in burrows (mice, skunks, 
squirrels] could be killed or entombed in collapsed burrows. Larger, more mobile mammal 
species, such as deer, canids, and bobcats, and some smaller mammals would vacate the 
area, potentially exposing them to increased competition from conspecifics already 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-51 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


occupying the area to which they were displaced and increased levels of predation because 
of unfamiliarity with the new area or lack of sufficient refugia. 

As discussed above, bank stabilization activities in the Guadalupe River watershed may 
expose soils contaminated with mercury. Effects of methylmercury exposure on wildlife can 
include mortality (death], reduced fertility, slower growth and development, and abnormal 
behavior that affect survival, depending on the level of exposure (Scheuhammer et al. 2007, 
USEPA 2010], 

Invertebrates. Invertebrates occur in and adjacent to channels where bank stabilization 
activities are planned. In these areas, invertebrates could be either killed directly (e.g., by 
crushing] or adversely affected by the loss of host plants or disturbance of refugia. For 
species such as moths and butterflies, host plants may be damaged or killed as a result of 
work site clearing (e.g., before the installation of bank armoring or during the creation of 
access roads or staging areas], crushing by equipment, trampling by personnel, and soil 
compaction by heavy equipment. In addition, these species may be adversely affected by 
habitat conversion, which could result from the unintentional introduction of non-native 
grasses and forbs to work sites. Bank stabilization activities often necessitate the operation 
of heavy equipment within the stream bed fafter dewatering! Movement of heavy 
equipment may compact the substrate, potentially killing benthic invertebrates, embedding 
gravel within finer sediments, and otherwise altering habitat conditions. 

Sediment Removal 

Fish. Sediment removal activities (e.g., sediment removal, access road construction, and 
staging area construction] may result in the removal of instream emergent vegetation and 
riparian vegetation along the channel banks, resulting in impacts similar to those described 
for loss of riparian vegetation as a result of bank stabilization activities. The removal of 
instream vegetation and riparian habitat may adversely affect fish as a result of increased 
water temperatures and reduced food availability. Additionally, the loss of instream cover, 
such as rocks, vegetation, and large woody debris, may adversely affect fish as a result of 
increased predation caused by a decrease in the availability of escape cover and the 
alteration of local hydraulics (e.g., increasing water velocity], which could reduce the 
frequency of riffle and pool habitat (Stillwater Sciences 2006], and the loss of refugia during 
high flows. Sediment removal also would result in the loss of substrate used by various fish 
for foraging or spawning, most notably the removal of spawning gravel for salmonids. 

As discussed under bank stabilization above, increased sedimentation may have adverse 
effects on salmonid spawning and overwintering habitat by filling in spaces between 
gravels and cobbles. Increases in turbidity and sediment input also may cause stress to fish 
because of feeding difficulties or displacement. Furthermore, settling of silt disturbed by 
sediment removal activities and contouring and grading of the channel following sediment 
removal may degrade spawning or rearing habitat in or downstream from work sites. 

As discussed for bank stabilization activities, SCVWD would capture and relocate native fish 
in accordance with its BMPs before the initiation of sediment removal activities that require 
temporary water diversions or dewatering along steelhead streams. During relocation 
operations, steelhead would be subject to harassment, pursuit, capture, mortality, and 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-52 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


related stresses associated with netting and electrofishing. Furthermore, fish that were not 
relocated and that remained within the work site may be subjected to degraded water 
quality, temporary blockage of migration, stranding in isolated pools, and mortality as a 
result of maintenance activities. 

Other effects of sediment removal on fish would be similar to those described above for 
bank stabilization. These would include the potential for fish injury or mortality during 
relocation efforts and adverse effects of fuel or chemical spills and mercury mobilization. 

However, the removal of sediment also may result in beneficial impacts on the ability of fish 
to move along streams, particularly for salmonids to migrate between estuarine areas and 
upstream spawning and rearing habitats, by improving upstream and downstream access. 

Amphibians and Reptiles. Similar to the potential direct effects of bank stabilization 
activities described above, potential impacts of sediment removal activities on amphibians 
and reptiles would include injury or mortality of individuals by equipment, vehicle traffic, 
and worker foot traffic; disturbance of boulders or cobbles that support egg masses; 
destruction of eggs/nests; silting over of eggs or tadpoles; exposure to petrochemicals, 
hydraulic fluids, and solvents; disruption of daily or seasonal movements; loss of basking 
sites and vegetative cover; exposure to mercury; disruption of foraging as a result of 
vibrations or seismic sounds; and exposure to increased numbers of predators. 
Furthermore, special-status amphibians and reptiles that were found during pre¬ 
construction surveys and relocated to suitable habitat outside of the work site may be 
subjected to physiological stress and be at greater risk of predation, and dewatering 
activities may result in a temporary loss of habitat, blockage of movement, and stranding or 
death of frog eggs and tadpoles. 

Birds. Similar to the potential effects of bank stabilization activities described above, 
potential impacts of sediment removal activities on birds would include mortality or injury 
of adults or eggs/young in nests as a result of crushing by equipment; nest abandonment 
because of increased noise and disturbance; exposure to increased competition as a result 
of displacement; exposure to increased numbers of predators; and increased exposure to 
mercury. 

The removal of instream vegetation associated with sediment removal activities may result 
in the temporary loss of habitats that served as breeding and/or foraging habitat, both in 
the sediment removal area and in access and staging areas. In addition, increased 
sedimentation or hazardous material spills from maintenance activities may result in the 
temporary or permanent degradation of water quality and, hence, habitat quality in marsh 
or aquatic habitats downstream from work sites and could impact habitat used by aquatic 
and riparian species. 

Mammals. Similar to the potential direct effects of Bank Stabilization activities described 
above, potential impacts of sediment removal activities on mammals would include 
mortality or injury by personnel or equipment; exposure to increased competition from 
conspecifics as a result of displacement; exposure to increased levels of predation because 
of unfamiliarity with the new area, lack of sufficient refugia, or increased numbers of 
predators; and exposure to increased levels of mercury. These effects would occur primarily 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-53 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


in non-instream staging and access areas and would be limited in the sediment removal 
area itself, as most mammals in the Project Area would be terrestrial. 

Invertebrates. Impacts to invertebrates from sediment removal would be similar to those 
described above for bank stabilization activities, although impacts to common aquatic 
invertebrates would be greater because of the greater area of sediment removal. Because 
sediment removal would be limited to the stream channel, direct impacts on terrestrial 
invertebrates would occur primarily because of the operation of equipment in non-instream 
areas during sediment removal activities (and in staging and access areas]. 

Vegetation Management 

Fish. As discussed under Bank Stabilization and Sediment Removal above, removal of 
instream and riparian vegetation may adversely affect steelhead as a result of increased 
water temperatures, reduced food availability, reduced escape cover, and the alteration of 
local hydraulics. In addition, decaying vegetation left in the channel following vegetation 
management activities may cause deterioration of water quality due to the depletion of 
oxygen. 

Settling of silt disturbed by vegetation removal activities may result in adverse effects as 
discussed under Bank Stabilization and Sediment Removal above, including potential 
impacts on salmonid spawning and overwintering habitat and stressing of fish caused by 
feeding difficulties or displacement. 

Proposed vegetation management activities would include the application of herbicides, the 
U.S. Environmental Protection Agency [USEPA] has conducted ecological risk assessments 
to determine the potential risks of labeled uses of several herbicides, including three 
proposed for use by SCVWD (glyphosate, pendimethalin, and triclopyr], on Pacific 
salmonids. These assessments are useful in evaluating potential effects of herbicide use on 
fish species in general for the Project Area. Evaluated herbicides proposed for use by 
SCVWD are as follows, with a summary of USEPA's effects determination: 

• Glyphosate: use of the aquatically approved formulation at labeled rates 
would result in no effect on steelhead. 

■ Pendamethaline: no effect on steelhead. 

■ Triclopyr: used as per the label with no exposure to the watercourse, use 
results in no impact to steelhead. If the material enters the watercourse, it is 
toxic to fish and results in mortality to steelhead. 

Thus, use of these pesticides according to current label directions and the voluntary 
guidelines provided in the 2000 USEPA bulletin, Protecting Endangered Species, Interim 
Measures for Use of Pesticides in Santa Clara County, is not expected to result in direct 
adverse effects on fish. Nevertheless, herbicides may affect fish indirectly as a result of 
reduction in the availability of food items (e.g., invertebrates] and in the suitability of 
habitat (e.g., reduction in abundance of aquatic and terrestrial plants], 

SCVWD would continue to use a surfactant to enhance the performance of herbicides. 
Surfactants aid the ability of an herbicide to penetrate the surface of vegetation by 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-54 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


increasing its ability to spread over vegetation, stick to foliage, and penetrate thick cuticles. 
For aquatic herbicides, the use of a surfactant is typically necessary to achieve reasonable 
levels of control. In instances where surfactants are absent from the tank mix, the level of 
control is often reduced. A reduction in control results in the need for a greater return 
frequency, which translates to more herbicide being used in the system and more frequent 
disturbance to the site. 

In general, aquatic species (e.g., fish and amphibians] are more susceptible to adverse 
effects than terrestrial wildlife because of the potential for surfactants to alter cell 
permeability, thus increasing the potential for absorption of chemicals through their thin, 
moist skin. Some surfactants, particularly those that are nonylphenol-based, have been 
documented to result in chemical-induced lethargy and unconsciousness in fish, which can 
result in an increased risk of predation, as well as estrogenic effects (Smith et al. 2004, USFS 
2007], However, as described in the SMP Manual (Appendix A], SCVWD proposes to limit 
surfactant use to the products that are documented to have the least toxic effect to aquatic 
life, Agri-dex and Competitor. Both of these surfactants are oil-based (Competitor is 
vegetable oil based while the primary ingredient in Agri-dex is a paraffin-based oil] and 
function by increasing the absorption of herbicides through plant tissues. They are 
especially useful in increasing the penetration of herbicides through the bark of woody 
brush or tree stems (Bakke 2007], A study on the toxicity of surfactants to juvenile rainbow 
trout concluded that Agri-dex was less toxic to rainbow trout than two other commonly 
used surfactants, R-ll and LI 700 (Smith et al. 2004], and the 2006 Supplemental 
Environmental Assessment of the National Oceanic and Atmospheric Administration 
(NOAA] Fisheries Implementation Plan for the Community Based Restoration Program (NOAA 
2006] concluded that Agri-dex was among the surfactants least toxic to marine and aquatic 
organisms (it is unknown whether Competitor was assessed]. 

During the course of the Proposed Project, new surfactants or improved chemistries may be 
proposed to improve the efficacy of the program or improve protection to biological 
resources. The proposal of any new materials would include toxicological data for review by 
stakeholders. This would provide a process for review and approval before inclusion in the 
program. 

Proposed vegetation management activities also may have beneficial impacts on fish. A 
recent study on the distribution, abundance, growth, and habitat use of steelhead in Uvas 
Creek (Casagrande 2010] determined that juvenile steelhead survival and growth in Uvas 
Creek from Uvas Road downstream to Highway 152 is currently limited, in part, because of 
the high shading and low light levels caused by the dense riparian forest. The author 
concludes that selective removal of trees within this reach to reduce shading and increase 
light levels would improve the feeding efficiency of juvenile steelhead and lead to more 
abundant algal growth. In turn, more abundant algal growth would not only lead to an 
increase in the invertebrate population (a steelhead food source] but also would filter 
turbid waters released from upstream reservoirs. Thus, vegetation management activities 
in at least some portions of the Project Area may benefit steelhead by reducing the density 
of the riparian canopy. 

Amphibians and Reptiles. Similar to the potential direct effects of bank stabilization 
activities described above, potential impacts of vegetation management activities on 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-55 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


amphibians and reptiles would include mortality of individuals crushed by equipment, 
vehicle traffic and worker foot traffic; disturbance of boulders or cobbles that supported egg 
masses; destruction of eggs/nests; silting over of eggs or tadpoles; exposure to 
petrochemicals, hydraulic fluids, and solvents; disruption of daily or seasonal movements; 
loss of basking sites; disruption of foraging as a result of vibrations or seismic sounds; and 
exposure to increased numbers of predators. Furthermore, special-status amphibians and 
reptiles that were found during pre-construction surveys and relocated to suitable habitat 
outside of the work site may be subjected to physiological stress and greater risk of 
predation. 

Proposed vegetation management activities would include the application of herbicides. 
Amphibians in particular could potentially be impacted via absorption of chemicals through 
their thin, moist skin. USEPA has conducted ecological risk assessments to determine the 
potential risks of labeled uses of several herbicides, including four proposed for use by 
SCVWD (glyphosate, imazapyr, pendimethalin, and triclopyr], on the federally listed 
California red-legged frog. These assessments are useful in evaluating potential effects of 
herbicide use on other amphibian species in the Project Area. Evaluated herbicides 
proposed for use by SCVWD are as follows, with a summary of USEPA’s effects 
determination. 

* Glyphosate: Likely to affect adversely aquatic-phase California red-legged 
frog via indirect effects through reduction in prey (non-vascular plants] and 
habitat (aquatic and terrestrial plants]. No direct effects would occur on the 
aquatic-phase California red-legged frog for any of the terrestrial or aquatic 
uses. Likely to adversely affect the terrestrial-phase California red-legged 
frogs via both direct effects and indirect effects following reduction in prey 
(terrestrial invertebrates, terrestrial-phase amphibians and mammals] and 
habitat (terrestrial plants]. 

■ Imazapyr: Likely to affect adversely the California red-legged frog via 
indirect effects on habitat and/or primary productivity (i.e., ecosystem 
structure and function for both the aquatic plant community and riparian 
vegetation]. No direct effects are anticipated. 

■ Pendimethalin: Likely to affect adversely the California red-legged frog via 
both direct and indirect effects on both terrestrial and aquatic phases of the 
frog. 

■ Triclopyr: Likely to affect adversely the California red-legged frog via both 
direct and indirect effects on both terrestrial and aquatic phases of the frog. 

As a result, the use of herbicides for vegetation management could adversely affect the 
health of amphibians; though BMPs would be implemented to reduce these effects, as 
described below. SCVWD would continue to use herbicides in compliance with the current 
applicable state and federal laws and in accordance with the PRESCRIBE (Pesticide 
Regulation's Endangered Species Realtime Internet Bulletin Engine] database that is 
managed by the California Department of Pesticide Regulation. Herbicides also may affect 
amphibians indirectly as a result of reduction in the availability of food items (e.g., 
invertebrates] and in the suitability of habitat (e.g., reduction in abundance of aquatic and 
terrestrial plants]. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-56 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


As noted for fish above, SCVWD also proposes to use surfactants designed for aquatic 
applications as part of its herbicide program. Although the potential exists for absorption of 
chemicals through the thin, moist skin of amphibians, SCVWD purposes to limit surfactant 
use to the products that are documented to have the least toxic affect to aquatic life, Agri- 
dex and Competitor. 

Birds. Similar to the potential effects of bank stabilization activities described above, 
potential impacts of vegetation management activities on birds would include mortality or 
injury of adults or eggs/young in nests crushed by equipment; nest abandonment resulting 
from increased noise and disturbance; exposure to increased competition because of 
displacement; exposure to increased numbers of predators; and increased exposure to 
mercury. 

Most importantly, the removal of vegetation would result in a loss of nesting, foraging, and 
roosting habitat in the form of riparian and wetland vegetation. Riparian habitats in Santa 
Clara County support very high densities and diversity of birds (Rottenborn 1997], 
Vegetation management effects would be largely temporary in any specific area, although 
the repeated nature of these impacts would limit the regeneration of woody riparian 
vegetation. Bird diversity generally increases with increasing foliage height diversity, or 
stratification of the vegetation (MacArthur and MacArthur 1961], As a result, inhibiting the 
development or maintenance of a multi-layered riparian forest through vegetation 
management is expected to reduce bird diversity. Furthermore, because the densities of 
native riparian birds tend to increase with increasing vegetation volume (Mills et al. 1991], 
vegetation management activities that reduced the volume of vegetation (i.e., how dense the 
vegetation was] could reduce bird abundance. As a result, vegetation management would 
adversely affect some aspects of the riparian bird community. For species that occurred 
primarily in early successional habitats, the vegetation management component would help 
to maintain such habitat over the long term. For species associated with more mature 
forests, the repeated management of younger vegetation, which would prevent it from 
becoming mature, may result in the long-term decline in mature riparian forests. Hazard 
tree removal may result in the loss of snags or other larger trees that otherwise would 
provide habitat for a variety of birds. 

Loss of understory vegetation resulting from pruning, mowing, and limbing up would 
reduce habitat for understory birds and could reduce dispersal ability of bird species 
associated with dense vegetation, as such species may be reluctant to move through areas 
without suitably dense cover. Limbing up would occur primarily along the slopes of levees 
as mandated by USACE standards, while pruning could occur in a number of areas, 
particularly along access roads. Hand pruning could occur in up to 40 acres of new work 
areas during the period 2012-2022. Pruning will occur on woody vegetation in order to 
restore conveyance capacity of a creek reach, provide visual inspection of District facilities, 
and to provide access clearance on roadways (not projected in 2002] and for bank 
stabilization projects. Hand pruning may also be performed for ecological/stewardship 
purposes. 

General work activity would cause most local species to avoid the area until the activity was 
finished. In the post-construction phase, birds would return to the area as it re-vegetated. 
Loss of vegetation during maintenance activities could reduce the amount of prey available 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-57 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


for birds that foraged in the work site. However, some birds would take advantage of prey 
that was flushed out of the area and into the open during construction. 

Mammals. Similar to the potential effects of bank stabilization activities described above, 
potential impacts of vegetation management activities on mammals would include mortality 
or injury by personnel or equipment; exposure to increased competition from conspecifics 
as a result of displacement; and exposure to increased levels of predation caused by 
unfamiliarity with the new area, lack of sufficient refugia, or increased numbers of 
predators. Removal of riparian and wetland vegetation also would remove habitat and 
cover for mammals, and loss of understory vegetation resulting from pruning or mowing 
could reduce dispersal ability of species associated with dense vegetation. As such, species 
may be reluctant to move through areas without suitably dense cover. For species 
associated with more mature forests, the repeated management of younger vegetation, 
which would prevent it from becoming mature, may result in the long-term decline in 
mature riparian forests. Hazard tree removal may result in the loss of snags or other larger 
trees that could provide roost sites for bats. 

Invertebrates. Similar to the potential effects of bank stabilization activities described 
above, potential impacts of vegetation management activities on invertebrates would 
include mortality or injury from crushing by personnel or equipment. In addition, these 
species could be adversely affected by the loss of host plants as a result of mechanical, 
physical, or chemical (i.e., herbicide] clearing in the work site; soil compaction; and damage 
to host plants. Furthermore, these species may be adversely affected by the conversion of 
habitat, which could occur after the unintentional introduction of non-native grasses and 
forbs to areas on or near serpentine soils. 

Management of Animal Conflicts 

Fish. Surface application of erosion control blankets, pyramat, and chain link for the 
purpose of animal conflicts management may result in a loss of vegetation that was 
overhanging and shading the active channel. As discussed above, riparian vegetation plays 
an important role in determining the structure and function of fish habitat, and the loss of 
such vegetation could result in increased stream temperatures and a loss of escape cover 
for fish. 

Discharge of sediments into the channel as a result of ground-disturbing activities on levee 
surfaces (e.g., filling or compacting of crevices/holes], or spills/leaks of fuels and other 
chemicals, may result in adverse effects as discussed under Bank Stabilization and Sediment 
Removal above, including potential impacts on salmonid spawning and overwintering 
habitat and stressing of fish because of feeding difficulties or displacement. The use of 
certain rodenticides, such as strychnine and zinc phosphide, to control burrowing mammals 
on levees would be unlikely to result in adverse water quality effects, as these rodenticides 
would be applied directly in burrows rather than being broadcast over the surface. 

Amphibians and Reptiles. Similar to the potential direct effects of bank stabilization and 
sediment removal activities described above, potential impacts on amphibians and reptiles 
resulting from the management of animal conflicts would include mortality of individuals 
crushed by equipment, vehicle traffic, and worker foot traffic; disturbance of boulders or 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-58 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


cobbles that supported egg masses; destruction of eggs/nests; silting over of eggs or 
tadpoles; exposure to petrochemicals, hydraulic fluids, solvents and lethal baits; disruption 
of daily or seasonal movements; loss of basking sites; disruption of foraging; and exposure 
to increased numbers of predators. Furthermore, special-status amphibians and reptiles 
that were found during pre-construction surveys and relocated to suitable habitat outside 
of the work site may be subjected to physiological stress and greater risk of predation. 

Direct mortality and a loss of subterranean habitat for amphibians and reptiles may occur 
because of filling or compacting of crevices/holes on levee surfaces or slopes. In addition, 
control of small mammal populations would result in a reduction in the availability of 
refugia for amphibians and reptiles. Species that may be adversely affected would include 
fossorial species and species that sought refuge in small mammal burrows to prevent 
dehydration during arid conditions or as an escape mechanism for predators. Loss of 
subterranean habitat may result in the displacement of small mammals and invertebrates 
that served as a food source for some species of amphibians and reptiles. 

In addition to direct loss of subterranean habitat, a reduction in the quantity of 
subterranean habitat available for amphibians and reptiles would occur from surface 
application control methods aimed at preventing rodent activity. The use of certain 
rodenticides (e.g., strychnine and zinc phosphide] to prevent animal conflicts on levees may 
result in the secondary poisoning of amphibians (e.g., California red-legged frog and 
California tiger salamander] resulting from dermal exposure (amphibians have thin, 
permeable skin] to bait placed in burrows or consumption of invertebrates that had 
consumed the poison bait (USEPA 2009], Furthermore, application of pyramat or other 
blanket-like surface barriers used to prevent rodent burrowing may result in the 
entrapment of amphibians and reptiles, leading to death by predation, starvation, or 
desiccation. 

Birds. As discussed above, birds that foraged or roosted in the work site would be impacted 
while heavy ground disturbance, noise, and vibration caused by the work activity (e.g., 
filling or compacting of crevices/holes on levee surfaces or slopes] proceeded. Individuals 
(especially young in nests] could be killed or injured during maintenance activities; the 
accompanying increase in noise and human presence near active nests could result in the 
abandonment of nests, and possibly the loss of eggs or young as a result; and the increased 
activity associated with maintenance activities may affect the behavior of birds, causing 
them to avoid work sites and possibly exposing them to increased competition and 
predation. 

Increases in human concentration and activity associated with maintenance activities in the 
vicinity of suitable habitat also may result in an increase in native and non-native predators 
that were attracted to trash left in the work site and a reduction in the quality of breeding, 
foraging, or upland refuge habitat from the introduction of non-native vegetation. In 
addition, surface application of erosion control blankets, pyramat, and chain link for the 
purpose of animal conflicts management may affect the character of the vegetation on the 
levee and, thus, the composition of bird species that would use the treated levee slopes. 

Filling or compacting of crevices/holes on levee surfaces or slopes may kill or injure 
burrowing owls (especially young or adults in burrows] crushed by maintenance personnel 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-59 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


or equipment because they nested underground. In addition, the filling of burrows, 
compaction of soils, or placement of armor material to secure levee surfaces and prevent 
rodent activity would result in a loss of suitable habitat for the burrowing owl (see Impact 
Bio-23 for additional detail]. Furthermore, small mammal control may reduce the suitability 
of habitat for birds that foraged in the work site by reducing the availability of prey (e.g., 
small burrow-dwelling rodents]. The use of certain rodenticides (e.g., strychnine, 
anticoagulants such as chlorophacinone and diphacinone] to prevent animal conflicts on 
levees may result in the secondary poisoning of birds that consumed rodents or 
invertebrates that had consumed the poison bait (USEPA 2009], 

Mammals. Because burrowing mammals are the primary target of animal conflicts 
management, obvious direct impacts on target mammals would result from the poisoning 
and trapping of small mammals, particularly California ground squirrels and valley pocket 
gophers, and the removal of their burrows. Individuals could be crushed or entombed 
within their burrows, and some species, particularly ground squirrels, cottontails, and deer 
mice would have to expend energy to find or dig new underground refuge sites. Carnivorous 
and omnivorous species would lose some food resources with the loss of underground prey 
species. 

Surface application of erosion control blankets, pyramat, and chain link for the purpose of 
animal conflicts management may result in direct and indirect impacts on mammal species. 
Similar to the impacts discussed for birds, the potential impacts on mammals would depend 
on the material used. Blanket-like materials could trap small mammals and cause mortality. 
Alternatively, blanket materials could act as cover for species like the California vole, which 
may be attracted to food resources beneath the barrier but also would be protected from 
larger predators above the barrier. The chain link barrier would have no impact on small 
mammals that could access the surface through the open pattern. Medium to large sized 
mammals, like skunks, ground squirrels, and coyotes would lose refuge sites because 
burrowing by larger mammals would be prevented by any of the surface barriers. 

The use of certain rodenticides (e.g., strychnine and anticoagulants such as chlorophacinone 
and diphacinone] to prevent animal conflicts on levees may result in the secondary 
poisoning of larger mammals that consumed rodents or invertebrates that had consumed 
the poison bait (USEPA 2009], Other impacts would be similar to the potential direct effects 
of bank stabilization activities described above, including mortality or injury by personnel 
or equipment; exposure to increased competition from conspecifics as a result of 
displacement; and exposure to increased levels of predation because of unfamiliarity with 
the new area, lack of sufficient refugia, or increased numbers of predators. 

Invertebrates. Similar to the impacts on invertebrates described above for bank 
stabilization activities, management of animal conflicts may result in the mortality or injury 
of invertebrates crushed by personnel or equipment and alteration of habitat. Removal of 
burrows that provided refugia for invertebrates would reduce habitat for these species. In 
addition, individuals could be adversely affected because of the loss of host plants. Host 
plants may be damaged or killed by soil compaction, creation of access roads or staging 
areas, and surface application of erosion control materials. Furthermore, these species may 
be adversely affected by the conversion of habitat, which could occur by the unintentional 
introduction of non-native grasses and forbs to work areas. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-60 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Quantification of Impacts 

For this evaluation, impacts on both common and special-status animals were assessed 
based on the potential for individuals or populations of animal species, or their habitat, to 
be disturbed, degraded, or lost during stream maintenance activities. Impacts on animal 
populations and communities were evaluated by comparing the quantity and quality of 
habitat present in the Project Area under baseline conditions to anticipated conditions after 
implementation of the maintenance activities, and by considering the potential for 
individual activities to affect populations of these species. 

Criteria for Determining Significance 

For the purposes of this analysis, the Proposed Project would result in a significant impact 
on biological resources if it would: 

A. have the potential to substantially degrade the quality of the environment, 
substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife 
population to drop below self-sustaining levels, threaten to eliminate a plant or 
animal community, substantially reduce the number or restrict the range of a rare 
or endangered plant or animal; 

B. have a substantial adverse effect, either directly or through habitat modification, on 
an identified candidate, sensitive, listed, or special status species in any local, 
regional, state, or federal plan, policy, or regulation; 

C. have a substantial adverse effect on federally protected wetlands as defined by 
Section 404 of the Clean Water Act (including but not limited to, marsh, vernal pool, 
coastal] through direct removal, filling, hydrological interruption, or other means; 

D. have a substantial adverse effect on any other sensitive natural community 
identified in local, region, state, or federal plans, policies, or regulations (such as 
riparian habitat, oak woodlands, etc.]; 

E. interfere substantially with the movement of any native resident or migratory 
species or with established native resident or migratory wildlife corridors, or 
impede the use of native wildlife nursery sites; or 

F. conflict with the provisions of an adopted Habitat Conservation Plan, Natural 
Community Conservation Plan, or other approved local, regional, or state habitat 
conservation plan. 

Environmental Impacts 

Tables 3.3-5 and 3.3-6 summarize the acreages of impacts to certain habitats in non-tidal 
and tidal reaches that would result from sediment removal activities and each type of 
vegetation management activity that are projected for 2012-2022. These tables include all 
of these projected activities, including "new" impact areas and areas that have also been 
impacted by 2002-2012 SMP activities. These acreages include overlap in areas that may be 
affected by multiple activities; for example, if a specific acre were subjected to herbicide, 
hand removal, and hand pruning, then those impacts would be represented in the table by 
an acre of impact in each of those three categories in the table, totaling to 3 acres of impact 
even though only one acre was involved. As a result, this table over-estimates the actual 
total acreage of each habitat that would be impacted. Habitat types are based on AIS's 2010 
habitat mapping, described previously. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-61 


December 2011 
Project No. 10.005 



This page intentionally left blank 


Santa Clara Valley Water District 

3.3-62 

December 2011 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


Project No. 10.005 



3.3 Biological Resources 


Table 3.3-5. Projected Impact Acreages by Habitat Type and Activity, Non-tidal Reaches 






Habitat Type (acres) 






Herbaceous 

Sediment 

Aquatic 

Herbaceous 



Watershed 

Activity Type 

Woodlands 

(non-wetland) 

Wetland 

(wetland) 

(wetland) 

Shrub 

Misc. 

Lower Peninsula 

Sediment Removal 

3.587 

0.51 

2.200 

0.000 

0.625 

0.000 

4.084 


Herbicide 

6.52 

3.253 

N/A 

0.000 

0.209 

0.262 

7.765 


Hand Removal 

0.064 

0.000 

N/A 

0.000 

0.000 

0.000 

0.002 


Discing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Mowing 

0.967 

2.659 

N/A 

0.000 

0.008 

0.025 

0.604 


Hand Pruning 

0.139 

0.011 

N/A 

0.000 

0.000 

0.000 

0.084 

Lower Peninsula Subtotal 

11.277 

6.433 

2.200 

0.000 

0.842 

0.287 

12.539 

West Valley 

Sediment Removal 

2.065 

3.227 

8.530 

0.000 

0.798 

0.059 

1.426 


Herbicide 

22.639 

31.329 

N/A 

0.000 

2.066 

0.321 

25.161 


Hand Removal 

0.076 

0.01 

N/A 

0.000 

0.000 

0.005 

0.005 


Discing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Mowing 

1.816 

7.644 

N/A 

0.000 

0.314 

0.000 

0.358 


Hand Pruning 

0.225 

0.056 

N/A 

0.000 

0 

0.001 

0.102 

West Valley Subtotal 

26.821 

42.266 

8.530 

0.000 

3.178 

0.386 

27.052 

Guadalupe 

Sediment Removal 

31.89 

5.199 

14.640 

0.000 

1.091 

2.405 

13.654 


Herbicide 

42.051 

65.511 

N/A 

0.000 

1.916 

1.782 

19.619 


Hand Removal 

0.237 

0.052 

N/A 

0.000 

0.001 

0.015 

0.004 


Discing 

0.071 

1.15 

N/A 

0.000 

0.000 

0.000 

0.000 


Mowing 

25.006 

20.909 

N/A 

0.000 

1.242 

2.914 

15.517 


Hand Pruning 

0.221 

0.046 

N/A 

0.000 

0.001 

0.000 

0.003 

Guadalupe Subtotal 

99.476 

92.867 

14.640 

0.000 

4.251 

7.116 

48.797 

Coyote 

Sediment Removal 

45.564 

9.472 

28.090 

0.009 

0.786 

2.031 

4.702 


Herbicide 

30.24 

137.874 

N/A 

0.001 

34.432 

1.299 

33.286 


Hand Removal 

3.175 

0.993 

N/A 

0.000 

0.036 

0.069 

0.262 


Discing 

1.287 

5.199 

N/A 

0.000 

0.635 

0 

0.226 


Mowing 

8.151 

20.502 

N/A 

0.000 

0.000 

0.567 

1.776 


Hand Pruning 

11.27 

3.138 

N/A 

0.000 

0.045 

0.188 

0.586 

Coyote Subtotal 

99.687 

177.178 

28.090 

0.010 

35.934 

4.154 

40.838 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-63 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Table 3.3-5. Projected Impact Acreages by Habitat Type and Activity, Non-tidal Reaches 






Habitat Type (acres) 






Herbaceous 

Sediment 

Aquatic 

Herbaceous 



Watershed 

Activity Type 

Woodlands 

(non-wetland) 

Wetland 

(wetland) 

(wetland) 

Shrub 

Misc. 

SF Basin Total 

Sediment Removal 

83.106 

18.408 

53.460 


3.300 

4.495 

23.866 


Herbicide 

101.450 

237.967 

N/A 


38.623 

3.664 

85.831 


Hand Removal 

3.552 

1.055 

N/A 


0.037 

0.089 

0.273 


Discing 

1.358 

6.349 

N/A 

0.000 

0.635 

0.000 

0.226 


Mowing 

35.940 

51.714 

N/A 

0.000 

1.564 

3.506 

18.255 


Hand Pruning 

11.855 

3.251 

N/A 

0.000 

0.046 

0.189 

0.775 

SF Basin Total 

237.261 

318.744 

53.460 

0.010 

44.205 

11.943 

129.226 










Pajaro Basin Total 

Sediment Removal 

5.99 

10.763 

9.810 




3.743 


Herbicide 

49.097 

86.642 

N/A 




10.719 


Hand Removal 

4.173 

2.239 

N/A 




0.442 


Discing 

1.731 

8.584 

N/A 

0.000 


0.000 

10.596 


Mowing 

12.865 

36.979 

N/A 


0.286 

0.000 

6.494 


Hand Pruning 

2.334 

4.007 

N/A 


0.005 

0.037 

0.111 

Pajaro Basin Total 

76.190 

149.214 

9.810 

0.315 

1.672 

0.691 

32.105 


Notes: 

1. Includes areas that also were projected for maintenance (and/or maintenance was conducted) from 2002-2012. 

2. Acreages are shown for the total of each type, but overlaps between work types are not eliminated. 

3. Acreages incorporate the work area percentage to account for various intensities of work within a specific reach and includes areas that also were 
projected for maintenance (and/or maintenance was conducted) from 2002-2009. 

4. "Misc.” habitats include cultivated lands, row crops, vineyards, orchards, developed/urban areas, roads, reservoirs, open water, and similar areas. 

5. “Sediment wetland" refers to wetland and aquatic havitats fcombinedj projected to be impacted by sediment removal, based on calculations performed 
by SCVWD. taking into account the length of reaches where sediment removal is projected and the approximate widths of the wetland/aquatic habitat 
within those reaches. SCVWD then identified additional areas (i.e.. outside the “sediment wetland" polygons) where the various SMP Update activities were 
projected in areas mapped by AIS as aquatic habitats (summarized in those tables as “acquatic [wetland]" impacts and vegetation types that are considered 
herbaceous wetlands (summarized in those tables as "herbaceous [wetland]" impacts). 

Source: Data compiled by Horizon Water and Environment in 2011 based on information from SCVWD 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-64 


December 2011 
Project No. 10.005 





















3.3 Biological Resources 


Table 3.3-6. Projected Impact Acreages by Habitat Type and Activity, Tidal Reaches. 


Watershed 

Activity Type 

Habitat Type (ac) 

Woodlands 

Herbaceous 

(non¬ 

wetland) 

Sediment 

Wetland 

Aquatic 

(wetland) 

Herbaceous 

(wetland) 

Shrub 

Misc 

Lower Peninsula 

Sediment Removal 

3.704 

0.971 

0.370 

0.000 

0.316 

0.069 

2.539 


Herbicide 

0.000 

0.001 

N/A 

0.000 

0.000 

0.000 

0.001 


Hand Removal 

0.139 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Discing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Mowing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Hand Pruning 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 

Lower Peninsula Subtotal 

3.843 

0.972 

0.370 

0.000 

0.316 

0.069 

2.540 

West Valley 

Sediment Removal 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 


Herbicide 

0.048 

0.294 

N/A 

0.000 

0.337 

0.000 

0.57 


Hand Removal 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Discing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Mowing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Hand Pruning 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 

West Valley Subtotal 

0.048 

0.294 

0.000 

0.000 

0.337 

0.000 

0.570 

Guadalupe 

Sediment Removal 

2.82 

17.302 

18.080 

0.000 

1.611 

0.069 

1.892 


Herbicide 

0.000 

0.000 

N/A 

0.000 

0.021 

0.000 

0.000 


Hand Removal 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Discing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Mowing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Hand Pruning 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 

Guadalupe Subtotal 

2.820 

17.302 

18.080 

0.000 

1.632 

0.069 

1.892 

Coyote 

Sediment Removal 

0.127 

1.231 

3.050 

0.000 

0.541 

0.000 

2.053 


Herbicide 

0.000 

0.014 

N/A 

0.000 

0.18 

0.000 

0.098 


Hand Removal 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Discing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Mowing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Hand Pruning 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 

0.000 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-65 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Table 3.3-6. Projected Impact Acreages by Habitat Type and Activity, Tidal Reaches. 


Watershed 

Activity Type 

Habitat Type (ac) 

Woodlands 

Herbaceous 

(non¬ 

wetland) 

Sediment 

Wetland 

Aquatic 

(wetland) 

Herbaceous 

(wetland) 

Shrub 

Misc 

Coyote Subtotal 

0.127 

1.245 

3.050 

0.000 

0.721 

0.000 

2.151 

SF Basin 

Sediment Removal 

6.651 

19.504 

21.500 

0.000 

2.468 


6.484 


Herbicide 

0.048 

0.309 

N/A 

0.000 

0.538 




Hand Removal 

0.139 

0.000 

N/A 

0.000 

0.000 

0.000 



Discing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 



Mowing 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 



Hand Pruning 

0.000 

0.000 

N/A 

0.000 

0.000 

0.000 


SF Basin Total 

6.838 

19.813 

21.500 

0.000 

3.006 

0.138 

7.153 


Notes: 

1. Includes areas that also were projected for maintenance (and/or maintenance was conducted) from 2002-2012. 

2. Acreages are shown for the total of each type, but overlaps between work types are not eliminated. 

3. Acreages incorporate the work area percentage to account for various intensities of work within a specific reach and includes areas that also were 
projected for maintenance (and/or maintenance was conducted) from 2002-2009. 

4. "Misc.” habitats include cultivated lands, row crops, vineyards, orchards, developed/urban areas, roads, reservoirs, open water, and similar areas. 

5. “Sediment wetland" refers to wetland and aquatic havitats fcombinedl projected to be impacted by sediment removal, based on calculations performed 
by SCVWD. taking into account the length of reaches where sediment removal is projected and the approximate widths of the wetland/aquatic habitat 
within those reaches. SCVWD then identified additional areas (i.e.. outside the “sediment wetland" polygons) where the various SMP Update activities 
were projected in areas mapped by AIS as aquatic habitats (summarized in those tables as “acquatic [wetland]’’ impacts and vegetation types that are 
considered herbaceous wetlands (summarized in those tables as "herbaceous [wetland]’’ impacts). 

Source: Data compiled by Horizon Water and Environment in 2011 based on information from SCVWD 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-66 


December 2011 
Project No. 10.005 





















3.3 Biological Resources 


Impact BIO-1: Loss or Disturbance of Wetlands and Other Waters 
(Significance Criteria C and D; Less than Significant with Mitigation) 

Maintenance activities associated with the Proposed Project would result in the short¬ 
term, but repetitive, disturbance of wetland and aquatic communities, including both 
jurisdictional and non-jurisdictional wetlands and other waters, which provide valuable 
habitat for fish and wildlife. As described above under Determination of Impacts to Aquatic 
and Wetland Communities, these activities could result in the placement of fill, hydrological 
interruption (e.g., dewatering or diversion], alteration of bed and bank, degradation of 
water quality (e.g., increased sedimentation and turbidity, herbicide contamination], and 
other direct impacts. The activities would primarily result in the short-term loss and 
disturbance of wetlands and aquatic habitats; however, small permanent losses could 
occur because of the use of hardscape for bank stabilization activities. 

Over the next 10 years, sediment removal activities may occur in up to 42.8 miles of creeks 
and canals, including approximately 35.4 miles in the Santa Clara Basin and 7.4 miles in the 
Pajaro River Basin. Table 3.3-7 includes the total sediment removal work projected for 
2012-2022 and identifies how much of this work is estimated for new channel areas 
("Projected Sediment Removal, 2012-2022 but not 2002-2012"] and how much would 
occur in channels that were also forecast under the original 2002 program projections 
("Projected Sediment Removal, both 2002-2012 and 2012-2022"]. The values in Table 
3.3-7 indicate the number of miles in which some level of sediment removal would occur. 
However, because a "work area percentage" would be applied to these sediment removal 
activities (i.e., only a certain percentage of each reach would undergo sediment removal], 
the actual extent of creeks subject to sediment removal is expected to be less than what is 
reported in this table. 


Table 3.3-7. Projected Sediment Removal, 2012-2022 


Watershed 

2012-2022 
Total Projected 
Length 
(miles) 

Projected Sediment 
Removal, 2012- 
2022 but not 2002- 
2012 
(miles) 

Projected 
Sediment 
Removal, both 
2002-2012 and 
2012-2022 
(miles) 

Santa Clara Basin 




Lower Peninsula 

3.9 

0.7 

3.2 

West Valley 

3.8 

0.9 

2.8 

Guadalupe 

11 

8.7 

2.3 

Coyote 

16.7 

5.9 

10.8 

Pajaro Basin 

Pajaro 

7.4 

3.1 

4.5 

Total 

42.8 

19.3 

23.5 


Note: 

Values have not been adjusted for "work area percentage”; thus, the actual extent of impacts would 
be lower than reported here. 

Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-67 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


Certain types of vegetation management work (hand removal, herbicide, pruning, mowing, 
and discing] also are projected activities, as shown in Table 3.3-8. This table does not 
account for overlap in vegetation management activities along the same stream reaches or 
between different types of vegetation management. For example, if herbicide use were to 
occur in instream, bank/bench, levee slope, and levee top areas along a specific mile of 
creek, the herbicide use along that reach would be reflected as 4 miles of impacted creek 
rather than one mile. In addition, if pruning and mowing were to occur in that one-mile 
reach, the columns for those activities would reflect that one-mile impact as well. 
Therefore, Table 3.3-8 does not include a summary of the total stream miles that are 
projected to be subject to vegetation management activities from 2012-2022. Rather, this 
table is provided primarily to quantify the number of miles in which the various types of 
vegetation management are projected to occur during the period 2012-2022. 

Table 3.3-8. Projected Vegetation Management 2012-2022 


Watershed 

Hand 

Removal 

(miles] 

Herbicide 

(miles] 

Pruning 

(miles] 

Mowing 

(miles) 

Discing 

(miles) 

Santa Clara Basin j 

Lower Peninsula 

2.5 

47.8 

22.7 

3.8 

0 

West Valley 

3.2 

146 

61.7 

32.6 

0 

Guadalupe 

6.9 

277.7 

211.6 

146.8 

0.4 

Coyote 

88.6 

213.4 

159.5 

58.3 

0.5 

Pajaro Basin | 

Pajaro 

49.7 

162 

156.6 

45.9 

0.9 


Note: 

Values do not account for overlapping work areas. 

Source: Data compiled by Horizon Water and Environment in 2011 based on information from SCVWD 

Wetlands serve a variety of important functions, such as sediment stabilization, 
sediment/toxicant retention, nutrient removal/transformation, and aquatic and terrestrial 
wildlife species habitat. These functions may be adversely affected as a result of sediment 
removal, vegetation management, bank stabilization, and other Proposed Project activities. 

The vast majority of wetlands and aquatic habitats providing important ecological 
functions and values are considered jurisdictional waters of the U.S. by the USACE. 
However, the canals subject to SMP activities are not expected to be considered waters of 
the U.S., although this determination ultimately will be made by the USACE. Impacts to 
unvegetated segments of these canals would not result in substantial adverse effects on 
wetland or aquatic functions and values, as they would simply result in minor modification 
(e.g., through sediment removal] of unvegetated areas. However, some pockets of 
vegetated wetland that are not expected to be considered jurisdictional wetlands are 
present within the canals. These wetlands do provide important ecological functions and 
values, serving as habitat for wildlife and, in some areas, supporting the Mt. Hamilton 
thistle, a special-status plant. Loss of these wetlands would result in a substantial impact 
even though they are likely non-jurisdictional. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-68 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


As reported in the 2002 SMP FEIR, SCVWD studies have found that wetland vegetation in 
some areas often quickly re-establishes following sediment removal activities. The 
Instream Wetland Vegetation Regrowth Study (Rankin and Hillman 2000] found 65 percent 
and 98 percent average regrowth within 1 and 2 years, respectively, after 1997 sediment 
removal at six non-tidal freshwater study sites. Average regrowth on two tidal study sites 
was less, at 21 percent and 29 percent after one and two years, respectively. The pattern of 
rapid re-establishment, with greater rates in non-tidal than in tidal areas, was supported 
by regrowth study results on four additional 1998 sediment removal sites. After one year, 
those sites supported more non-tidal wetland than was present before sediment removal 
and almost 70 percent of the tidal wetland that was present before sediment removal. 

Vegetation dominance and quality (as represented by vegetation type, total percent cover 
of vegetation, and relative percent cover of native and non-native species] were similar 
between pre- and post-project years on both sediment removal work sites and reference 
sites on which sediment removal had not been conducted for several years. At most sites, 
however, some vegetation shifts did occur. Most shifts were neutral or positive, from the 
perspective of long-term effects on native communities, including full or partial transition 
from one native-dominated vegetation type to another, disappearance of a non-native 
vegetation type, or increased total percent cover. Potentially negative changes occurred 
less frequently, including slightly increased invasive species cover, appearance or increase 
in amount of a non-native vegetation type, and decrease in total percent cover. 

The Instream Wetland Vegetation Regrowth Study (Rankin and Hillman 2000], as well as 
anecdotal observations by SCVWD biological and vegetation management staff, indicate 
that wetland extent and species composition are affected by vegetation management. 
Herbicide spraying likely reduces the amount of the target vegetation present (mostly 
cattails] in freshwater and tidal wetlands in years following the treatment. By targeting 
perennial emergent vegetation with herbicides, which kill the entire plant, other wetland 
vegetation types, such as other herbaceous wetland species and non-native annuals, 
appear to be favored. In contrast, cattails that are removed by manual methods such as 
cutting re-sprout each year. Therefore, hand removal does not result in a reduction in 
abundance of erect emergent vegetation as occurs with herbicide use. On the other hand, 
herbaceous wetland vegetation benefits from the targeted removal of woody riparian 
saplings, either by herbicide or hand removal, which would otherwise shade out wetland 
plants. 

The Project Area for the Instream Wetland Vegetation Regrowth Study mostly included 
leveed and excavated channels in lower valley sites where work had been done previously. 
Therefore, the results of that study are not necessarily applicable to the new work areas, 
especially higher-elevation areas where sediment removal has not previously been 
performed. Notably, species composition in these higher-elevation areas is different, and 
these species are likely much less adapted to disturbance from typical SCVWD 
maintenance activities. Furthermore, these studies occurred during wet years, and their 
applicability during drought years is unknown. 

SCVWD would implement a number of measures to address the impacts of Proposed 
Project activities on wetlands and other waters. First, implementation of BMPs would 
reduce impacts on these habitats by minimizing the spatial extent of maintenance 
activities, scheduling activities to avoid high-water periods, and designing maintenance 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-69 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


activities to result in the least impact to the stream channel, while still meeting flood 
conveyance objectives. In addition, SCVWD would implement the relevant project and 
post-project BMPs during maintenance activities to minimize impacts to water quality 
(e.g., resulting from erosion and sedimentation; contamination by fuels, herbicides, etc.]. 
These BMPs are listed below; descriptions of each are provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-1: In-Channel Work Windows 

BMP GEN-2: Instream Herbicide Application Work Window 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-16: In-Channel Minor Activities 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-21: Staging and Stockpiling of Materials 

BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 

BMP VEG-3: Use Appropriate Equipment for Instream Removal 

BMP VEG-6: Standard Grazing Procedures 

BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 
BMP BANK-2: Concrete Use near Waterways 
BMP REVEG-1: Seeding 

Conclusion 

Implementation of these BMPs would minimize disturbance of wetlands and other waters. 

The vast majority of impacts to acreage of wetlands and other waters would be short-term, 
because aquatic habitats would be maintained despite Proposed Project activities (e.g., no 
loss of aquatic habitat would occur because of any maintenance activity other than, 
perhaps, bank stabilization]. In addition, at least along valley-floor channels, many 
vegetated wetland areas would restore themselves within 1-2 years following sediment 
removal or vegetation management, as described previously. Nevertheless, the Proposed 
Project would result in temporal losses of wetland and aquatic habitat functions and 
values, possible type conversion of wetlands (e.g., from wetlands dominated by certain 
plant species to wetlands dominated by others], and potentially permanent losses of 
wetlands and other waters. Even with BMPs, complete avoidance of fill and water quality 
degradation could not be accomplished while still meeting the projected goals and public 
health and safety directives. 

Thus, in the absence of any mitigation measures, this impact is considered significant 
because it would result in short-term degradation and temporary and permanent losses of 
ecologically valuable wetlands and aquatic habitats, including jurisdictional wetlands and 
other waters (Significance Criteria C and D], and temporary disruption of stream 
continuity during sediment removal activities within the channel. Impacts on special- 
status wildlife species resulting from disturbance or loss of wetland and aquatic habitat 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-70 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


are addressed in separate impact discussions below. Mitigation Measure BIO-1 would be 
implemented to reduce residual impacts to wetlands and other waters to a less-than- 
significant level. 

Mitigation Measure BIO-1: Implement Compensatory Mitigation for Wetlands 
and Other Waters 

The compensatory mitigation package, which is detailed in Appendix C, 2012-2022 SMP 
Update Mitigation Approach Memorandum, shall be implemented to compensate for new 
impacts (i.e., work areas not included in the 2002-2012 work projections] on wetlands 
(both jurisdictional and non-jurisdictional] and on jurisdictional "other waters"; no 
mitigation is necessary for impacts to non-jurisdictional "other waters", which are limited 
to unvegetated areas of inoperable canals. For work areas included in the 2002-2012 work 
projections, previously provided mitigation would continue to serve as mitigation in 
perpetuity, as no new significant environmental effects or a substantial increase in the 
severity of previously identified significant effects are anticipated under the SMP Update. 

Following the procedure described in Appendix C, the SCVWD would refine the 
quantification of impacts to wetlands and other waters that occur during a specific year, 
tallying the impact totals at the end of the year, and compensatory mitigation will be 
implemented the following year, in many cases. Exceptions will occur in cases in which 
compensatory mitigation is incorporated directly into Proposed Project work areas; in 
those cases, compensatory mitigation may be implemented during the same year in which 
impacts occur. Details regarding performance criteria for mitigation, as well as for 
monitoring and reporting, are described in Appendix C. 

According to the mitigation package, SCVWD will have several options for satisfying 
mitigation requirements for impacts to wetlands and other waters by the SMP. The two 
main types of mitigation that can be applied for impacts to non-tidal wetlands and other 
waters resulting from sediment removal, vegetation management, canal maintenance, and 
minor maintenance are “in perpetuity" mitigation and "pay as you go” mitigation. 

In perpetuity mitigation. For permanent impacts and, at the discretion of SCVWD, 
repetitive impacts to wetlands or other waters in a specific area, SCVWD will provide 
mitigation in perpetuity via one or more of the following methods: 

■ In-kind restoration /creation : SCVWD will restore, preserve, and manage wetlands and 
aquatic habitats, or substantially improve the quality of highly degraded wetlands and 
aquatic habitats at a ratio of 1.5:1, meaning 1.5 acres of wetlands or other waters shall 
be restored/created for every 1 acre of wetlands and other waters impacted by 
Proposed Project activities. 

■ In-kind preservation and enhancement : SCVWD will acquire, preserve, enhance, and 
manage lands that provide similar ecologic functions and values to the wetlands and 
other waters impacted by SMP maintenance activities. The acquisition and 
preservation/enhancement of these higher quality lands will occur at a ratio of 3:1, 
meaning 3 acres of wetlands or other waters shall be acquired, preserved, and 
enhanced for every 1 acre of wetlands and other waters impacted by Proposed Project 
activities. Enhancement may include modification of existing management, limited 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-71 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


planting, or invasive plant removal, or other activities to enhance wetland/aquatic 
habitat functions and values. 

■ Out-of-kind preservation of watershed lands : SCVWD will acquire, preserve, enhance, 
and manage watershed lands. These lands provide more general conservation, open 
space, and habitat values. Although acquired lands would not be specifically tied or 
matched in-kind to wetland impacts, as they can include a variety of non¬ 
wetland/aquatic habitats, their preservation and management will help to maintain 
the quality or wetlands and aquatic habitats through management focused on benefits 
to the aquatic environment, such as management to reduce erosion and sedimentation. 
The acquisition of more general watershed conservation lands will occur at a ratio of 
8:1, meaning 8 acres of land shall be acquired and restored for every 1 acre of 
impacted habitats resulting from Proposed Project activities. 

■ Enhancement or management of land that is owned by other agencies : SCVWD may 
collaborate with owners of land that is currently managed for open space or passive 
recreation. In such cases, SCVWD would not acquire the mitigation lands but would 
enter into an agreement with the landowners to provide management and financial 
support toward preserving or improving the lands toward beneficial outcomes, 
including improved habitats. In these cases, a detailed management plan for species or 
habitats would be SCVWD's responsibility and would not necessarily be managed by 
the landowner. The mitigation accounting for such “partnership projects" and how 
much mitigation would be provided to account for SMP Update activities would be 
reviewed and developed with regulatory staff on a case-by-case basis. 

For any of the three mitigation options above, the mitigation areas will be preserved and 
managed in perpetuity by SCVWD. Mitigation could occur on lands acquired or owned by 
SCVWD, or on permanently protected lands not owned by SCVWD but by another entity 
(e.g., an open space district or park lands]. These options would reduce impacts to 
wetlands and aquatic habitats to less-than significant levels by directly replacing wetlands 
(in-kind restoration/creation]; directly improving the functions and values of existing 
wetlands and maintaining those resources through long-term management (in-kind 
preservation and enhancement]; or indirectly enhancing and/or protecting wetland and 
aquatic functions and values by protecting watershed lands that contribute to wetland and 
aquatic habitat ecology and integrity (out-of-kind preservation of watershed lands]. The 
mitigation ratios for these three options were selected to reflect the relative value of each 
type of mitigation, with in-kind restoration/creation having the lowest mitigation ratio to 
reflect its direct compensation for lost wetlands, and out-of-kind preservation of 
watershed lands having the highest mitigation ratio to reflect its more indirect value in 
protecting and enhancing wetlands and aquatic habitats. Because acquisition lands will be 
conserved in perpetuity, the mitigation they provide will also serve the SMP in perpetuity. 
As a result, if in-perpetuity mitigation were applied to impacts to wetlands and other 
waters in a certain area, no further mitigation would be needed if repetitive impacts to that 
area were to occur, in perpetuity. 

Pay as you go mitigation. Unless it specifically decides to use in perpetuity mitigation to 
compensate for impacts to wetlands and aquatic habitats in a certain area (e.g., an area 
where sediment removal or vegetation management will have frequent, repetitive 
impacts], SCVWD will use two programs (invasive plant management and riparian 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-72 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


planting] to provide incremental "pay as you go" habitat mitigation to compensate for 
annual impacts to wetlands and aquatic habitats from sediment removal and vegetation 
management activities. A mitigation ratio of 1.2:1 (area mitigated to area impacted] shall 
be applied for habitat impacts from sediment removal and vegetation management 
activities. SCVWD can use either the invasive plant management program or the riparian 
planting program (or a combination of the programs] to achieve this net mitigation target 
for annual activities. 

Invasive plant management. The primary goal of the invasive plant management program 
(IPMP] element of the SMP’s compensatory mitigation package is to preserve and improve 
habitat within Santa Clara County streams and riparian corridors by reducing the 
population of invasive plant species. The IPMP will have a two-pronged approach: 

■ a systematic program with the longer-term objective of identifying, 
prioritizing, and controlling invasive plants throughout the Project Area; and 

■ an opportunistic, site-specific approach with the objective to remove invasive 
plants from individual SMP work sites. (As mitigation for vegetation 
management activities, each of the SMP maintenance sites will be evaluated 
for on-site invasive plant removal and control. Invasive plant management will 
focus on controlling species that are invasive at individual SMP work sites.] 

Riparian planting. The primary goal of the riparian planting component of the SMP 
mitigation package is to compensate for the loss of quality and quantity of native- 
dominated riparian habitat because of maintenance activities. Riparian planting will 
enhance habitat for birds, amphibians, and other wildlife using terrestrial riparian areas 
while providing shading, sources of organic matter and coarse woody debris, and water 
quality benefits to aquatic species. 

Opportunities for riparian planting and restoration will be evaluated at all vegetation 
management maintenance locations. SCVWD's preference will be to first prioritize riparian 
planting at maintenance sites, and in this way provide direct on-site mitigation for 
maintenance activities. Riparian planting and restoration will provide mitigation that 
directly addresses impacts associated with vegetation management activities. Where 
opportunities for onsite riparian planting and restoration are unavailable or highly 
constrained, SCVWD will identify offsite locations that can provide suitable mitigation 
opportunities. Off-site riparian planting restoration sites will be prioritized to: 

■ stream reaches with riparian restoration opportunities for sensitive fish 
and/or wildlife species; 

■ stream reaches where riparian restoration of existing riparian canopy gaps 
will improve connectivity between existing patches of high-quality riparian 
habitat; and 

■ stream reaches with riparian habitat gaps where invasive plant species have 
been treated to accelerate native riparian plant establishment and inhibit re¬ 
colonization by invasive plant species. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-73 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Although invasive species management and riparian planting do not result in the direct 
replacement of lost or degraded wetland habitat, they do contribute substantially to the 
protection and enhancement of aquatic functions. As a result, riparian buffer plantings 
have been recognized as an appropriate component of programs to mitigate impacts to 
jurisdictional wetlands and other waters of the U.S. by the USACE (2002], 

The “pay as you go" mitigation areas will not be preserved and managed in perpetuity. 
However, several factors were considered in determining that these components of the 
mitigation plan will reduce residual impacts to wetlands and aquatic habitats to less-than- 
significant levels: 

■ These "pay as you go" mitigation options will benefit wetlands and aquatic 
habitats indirectly, by increasing the functions and values of existing 
wetland and aquatic habitats. 

■ Any riparian planting area used as pay as you go mitigation for impacts to 
wetlands or aquatic habitats will remain unimpacted for at least 10 years; 
or, if the mitigation area is impacted within 10 years, it will then be replaced 
elsewhere. 

■ Pay as you go mitigation will be provided each time a specific area of 
wetlands or other waters is impacted. For example, if the same 1-acre area 
were impacted three times during the 10-year SMP Update period, then 3.6 
acres of pay as you go mitigation will be provided for impacts to that area 
during the 10-year period. 

■ Impacts to any specific area will degrade, but will not entirely remove, 
wetland and aquatic functions and values within the impact area. 

Mitigation for Bank Stabilization Impacts. Impacts to non-tidal wetlands and aquatic 
habitats resulting from bank stabilization will be provided via the methods described in 
Appendix C and using the mitigation ratios identified in Table 2-4. Softscap e r e pairs will b e 
s e lf - mitigating b e caus e th e y will not r e sult in long - t e rm adv e rs e e ff e cts. Mitigation may 
occur through a combination of replacement of “hard" stabilization measures with soft, 
biotechnical measures (either on the stabilization site or off-site] or out-of-kind via 
riparian revegetation as determined by a Mitigation Feasibility Assessment, as described in 
Appendix C. These measures will reduce impacts to wetlands and aquatic habitats 
resulting from bank stabilization by increasing the functions and values of existing wetland 
and aquatic habitats. 

Mitigation for Impacts to Tidal Wetlands and Other Waters. SCVWD will continue to 
implement mitigation measures adopted to reduce impacts for the SMP. Although the 2012 
project description has changed, this FSEIR has examined the Proposed Project changes 
and determined that the existing tidal marsh restoration mitigation measures will continue 
to reduce the Proposed Project impacts to less than significant. The 2012 SMP Update will 
be a continuation from the 2002 SMP. with some program modifications: although the 
work activities are updated, the original mitigation remains, along with the resulting 
benefits. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-74 


December 2011 
Project No. 10.005 








3.3 Biological Resources 


As mitigation for impacts to tidal habitats and tidal marsh species predicted to result from 
the 2002-2012 SMP work activities. SCVWD restored the "Island Ponds" (Ponds A19, A20, 
and A21], located between Coyote Slough and Mud Slough near Alviso, to tidal action. 
Restoring these ponds provided 30 acres of tidal habitat that is used by a variety of tidal 
marsh species. Monitoring has documented achievement of all performance criteria 
appropriate for the development of both vegetated tidal salt/brackish marsh and tidal 
aquatic habitat, includin g with the formation of nascent tidal marsh habitat, including 
extensive channel networks, within these ponds. 

The 2002 SMP work projections provided the basis for determining the SMP's initial, 
upfront compensatory mitigation. As a result of those projections, impacts to tidal habitats 
for the 2002-2012 SMP Update were calculated with a mitigation requirement of 30 acres 
of tidal restoration. SCVWD already has met this obligation by restoring 30 acres of tidal 
habitat with the "Island Ponds.” Thirty acr e s of tidal r e storation within th e Island Ponds 
was int e nd e d to s e rv e as mitigation for impacts to tidal habitats for th e 2002 - 2012 SMP. 
However, not all of the 2002 projected work has actually been performed. Thus, the 2002 
mitigation of 30 acres of restored tidal habitat paid for more work than was conducted. 
Based on the actual impacts from activities conducted between 2002-2012 Propos e d 
Proj e ct activiti e s , only 9 acres of tidal mitigation will h e is needed to compensate for those 
impacts. 

The 2002-2012 SMP created an upfront compensatory mitigation package to account for 
SMP impacts in perpetuity. The 2012-2022 SMP Update has modified the project 
description to refine maintenance work activity needs. The updated project description in 
this FSEIR is a continuation, with modifications, of the 2002-2012 SMP. 

SCVWD will remove the 2002 work activity projections that would have resulted in the 
need for 21 tidal habitat mitigation acres. The removal of these projections, therefore, will 
equate to having 21 acres of tidal habitat mitigation that is not attributed to ongoing SMP 
impacts. Th e r e for e . SCVWD cr e at e d 21 acr e s of e xc e ss tidal habitats. SCVWD will use the 
21 acres of e xc e ss tidal marsh habitat restoration as available mitigation for impacts to 
tidal wetlands and aquatic habitats, as well as tidal marsh species, that may occur under 
the 2012-2022 SMP Update. Physical br e aching of th e Island Pond l e v ee s and oth e r 
physical work r e quir e d for this tidal r e storation has alr e ady occurr e d, and no furth e r 
activiti e s (oth e r than continu e d monitoring of marsh d e v e lopm e nt p e r th e 2002 - 2012 
SMP monitoring r e quir e m e nts) ar e propos e d by SCVWD. 

It is possible that these mitigation measures may be refined during permitting with the 
USACE, RWQCB, and CDFG, in which case the refinements required by these resource 
agencies would be implemented. 

MM BIO-1 will mitigate impacts to wetlands and other waters, including jurisdictional 
waters of the U.S./state, to less-than-significant levels by replacing lost wetlands and 
aquatic habitats through restoration or by replacing the lost functions and values provided 
by these habitats through other means, such as non-native plant removal and watershed 
protection. Thus, MM BIO-1 will assure that the SMP does not result in a substantial 
adverse effect on federally protected wetlands or on sensitive wetland and aquatic 
communities. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-75 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Impact BIO-2: Loss or Disturbance of Woody Riparian Vegetation 
(Significance Criterion D; Less than Significant with Mitigation) 

Bank stabilization, sediment removal, and vegetation management activities would result 
in the loss and disturbance of woody riparian vegetation that occurred along the stream 
banks above the ordinary high water mark. As described above under Determination of 
Impacts to Non-Instream Sensitive Plant Communities, these activities could result in the 
loss of vegetation through directly removal, herbicide use, trampling, and other impacts. 

Although the effects of bank stabilization on riparian vegetation are difficult to quantify 
precisely, based on past work records, SCVWD stabilizes nearly one mile of stream bank 
per year (approximately 0.75 miles in the Santa Clara Basin and 0.25 miles in the Pajaro 
Basin], Impacts to riparian vegetation could occur during sediment removal activities as 
well (e.g., during access to sediment removal areas and movement of equipment for 
sediment removal], although predicting the impacts to riparian habitat quantitatively 
would not be possible beyond the linear miles of creek subject to sediment removal 
(summarized in Table 3.3-7] because sediment removal would target instream sediment. 

Impacts of projected vegetation management activities on woody riparian vegetation were 
summarized by SCVWD using AIS's vegetation mapping (to determine where instream 
woodland, forest, and scrub-shrub vegetation was located] and the 2012-2022 
projections. Table 3.3-9 summarizes these estimated impacts by watershed for riparian 
woodland/forest and scrub-shrub habitats. Because of overlap between certain types of 
vegetation removal activities (i.e., with multiple activities occurring in the same general 
area], the total number of acres that would be subject to impact by projected vegetation 
management activities would be lower than the totals in this table. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-76 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Table 3.3-9. Estimated Impacts to Riparian Woodland, Forest, and Scrub-Shrub from 
Projected Vegetation Management, 2012-2022 


Watershed 

Hand 

Removal 

(acres) 

Herbicide 

(acres) 

Pruning 

(acres) 

Mowing 

(acres) 

Discing 

(acres) 

Total 

(acres) 

Lower Peninsula 

0.2 

3.7 

0.1 

0.8 

0 

4.8 

West Valley 

0.1 

18.5 

0.2 

1.8 

0 

20.6 

Guadalupe 

0.2 

31.4 

0.2 

27.9 

0.1 

59.8 

Coyote 

3.3 

26.5 

11.4 

8.7 

1.3 

51.2 

Pajaro 

4.2 

40.7 

1.5 

9.3 

1.7 

57.4 

Total 

8.0 

120.8 

13.4 

48.5 

3.1 

193.8 


Note: 

Some of the activities in this table overlap within a specific area. Also. SCVWD may perform additional 

pruning that could affect up to 40 acres during the period 2012-2022. 

Source: Data compiled by Horizon Water and Environment in 2011 based on information from SCVWD 

Hand pruning has b ee n proj e ct e d in 40 acr e s of n e w work ar e as. Pruning will occur on 
woody v e g e tation in ord e r to r e stor e conv e yanc e capacity of a cr ee k r e ach, provid e visual 
insp e ction of District faciliti e s, and to provid e acc e ss cl e aranc e on roadways (not proj e ct e d 
in 2002) and for bank stabilization proj e cts. Hand pruning may also b e p e rform e d for 
e cological/st e wardship purpos e s. The pruning projections in Table 3.3-9. totaling 13.4 
acres, were derived from SCVWD's database of reach-bv-reach projected activities. In 
addition, additional pruning are expected to be necessary in areas that are not vet 
completely defined, to restore conveyance capacity of a creek reach, provide visual 
inspection of SCVWD facilities, and provide access clearance on roadways, for bank 
stabilization projects and for ecological/stewardship purposes. As a result. SCVWD has 
allowed for the possibility that pruning may affect considerably more acreage than has 
been indicated in Table 3.3-9 and has set a cap of 40 acres of pruning for the entire 10-vear 
2012-2022 program. 

In addition, unprojected activities (e.g., management of animal conflicts and minor 
maintenance] could potentially result in the loss or disturbance of woody riparian 
vegetation. 

Vegetation that is removed by Proposed Project activities is expected to regrow, except in 
areas where bank stabilization would result in the permanent loss of natural streambank, 
or where capacity or other maintenance activities would require the permanent exclusion 
of vegetation. Thus, most Proposed Project impacts to riparian habitats would be 
temporary in that they would not preclude the potential for woody riparian vegetation to 
regrow. However, repetitive impacts to woody riparian vegetation would prevent 
regrowth, at least during the 10-year duration of the SMP Update. Proposed Project 
activities also may contribute towards the long-term modification of riparian plant 
communities if certain plant species were targeted. For example, young cottonwoods often 
are removed by vegetation management activities, which prevents these trees from 
maturing into the large trees that provide habitat for a number of wildlife species. 
Cottonwoods already suffer the effects of stream modification, including restrictions on the 
ability of streams in urban areas to meander, and thus regeneration of cottonwood- 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-77 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


dominated forests in urban Santa Clara County is poor. Proposed Project activities that 
would prevent the maturation of cottonwoods could contribute to the long-term decline in 
multi-aged cottonwood-dominated riparian forests in the county. 

Riparian communities are considered sensitive habitats in and of themselves. In addition, 
riparian habitats include two plant communities, sycamore alluvial woodland and oak 
woodlands, that also are considered sensitive. Impacts to sycamore alluvial woodland and 
oak woodlands are addressed in greater detail under Impact BIO-3. 

As discussed above, woody riparian habitats in the Project Area provide a wide range of 
biological functions for fish and wildlife, ranging from providing habitat for fish and other 
aquatic species to foraging and nesting habitat for birds, to movement corridors for 
numerous terrestrial species. As a result, impacts to riparian habitats would affect a 
variety of fish and wildlife species as well. Impacts on special-status plant and wildlife 
species resulting from disturbance or loss of riparian habitat are addressed in separate 
impact descriptions below. 

Riparian vegetation in some work sites would include herbaceous vegetation rather than 
woody vegetation. Herbaceous vegetation, which often includes species such as black 
mustard [Brassica nigra), poison hemlock ( Conium maculatum), perennial ryegrass 
[Lolium perenne), Italian thistle, bristly ox-tongue, sweet fennel [Foeniculum vulgare), and 
smilograss ( Piptatherum miliaceum), typically dominates the banks of reaches that would 
be frequently disturbed (including disturbance from ongoing maintenance activities]. Such 
vegetation regenerates quickly and, compared to woody riparian vegetation dominated by 
trees and shrubs, would provide relatively low functions and values for wildlife. As a 
result, impacts of Proposed Project activities on non-wetland, herbaceous riparian 
vegetation would not have substantial ecological effects. 

SCVWD would implement a number of measures to address the impact of Proposed Project 
activities on woody riparian vegetation, including limiting impacts to the minimum area 
required and conducting pruning according to the National ANSI A300 standards. These 
BMPs are listed below, and descriptions of each are provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-21: Staging and Stockpiling of Materials 

BMP GEN-23: Stream Access 

BMP GEN-28: Fire Prevention 

BMP REVEG-1: Seeding 

BMP REVEG-2: Planting Material 

Conclusion 

Implementation of these BMPs would minimize disturbance of woody riparian vegetation. 
Nevertheless, the Proposed Project would result in temporal losses of woody riparian 
functions and values and some permanent losses of woody riparian habitat because 
complete avoidance could not be accomplished while still meeting the project goals for 
public health and safety directives. Thus, significant residual impacts would remain. The 
impact of Proposed Project activities on woody riparian vegetation is considered 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-78 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


significant because it would result in short-term degradation of riparian habitat 
(Significance Criterion D] and temporary and permanent loss of riparian vegetation 
(Significance Criterion D], Mitigation Measure BIO-2 would be implemented to reduce this 
residual impact to a less-than-significant level. 

As discussed above, riparian vegetation in some work sites would include herbaceous 
vegetation rather than woody vegetation. Compared to woody riparian vegetation 
dominated by trees and shrubs, such vegetation regenerates quickly and generally 
provides relatively low functions and values for wildlife. As a result, impacts of Proposed 
Project activities on non-wetland, herbaceous riparian vegetation are less-than-significant, 
and no mitigation for such impacts is required (although impacts to herbaceous wetland 
vegetation, which may extend up into riparian areas from the creek channel, would be 
significant as discussed under Impact BIO-1], 

Mitigation Measure BIO-2: Implement Compensatory Mitigation for Woody 

Riparian Vegetation 

The compensatory mitigation package, which is incorporated into the Proposed Project 
and detailed in Appendix C, shall be implemented to compensate for new impacts (i.e., 
work areas not included in the 2002-2012 work projections] on woody riparian 
vegetation. For work areas included in the 2002-2012 work projections, previously 
provided mitigation would continue to serve as mitigation in perpetuity, as no new 
significant environmental effects or a substantial increase in the severity of previously 
identified significant effects are anticipated under the updated program. 

Following the procedure described in Appendix C, the SCVWD would refine the 
quantification of impacts to riparian vegetation that occur during a specific year, tallying 
the impact totals at the end of the year, and compensatory mitigation will be implemented 
the following year, in many cases. Exceptions will occur in cases in which compensatory 
mitigation is incorporated directly into the SMP work areas; in those cases, compensatory 
mitigation may be implemented during the same year in which impacts occur. Details 
regarding performance criteria for mitigation, as well as for monitoring and reporting, are 
described in Appendices C and Appendix L. 

According to the mitigation package, SCVWD will have several options for satisfying 
mitigation requirements for impacts to riparian vegetation by the SMP. The two main 
types of mitigation that can be applied for impacts to riparian vegetation resulting from 
sediment removal, vegetation management, canal maintenance, and minor maintenance 
are "in perpetuity" mitigation and "pay as you go" mitigation. These mitigation options 
would be applied to riparian vegetation as described in Mitigation Measure BIO-1 for 
wetlands and other waters. 

For any of the three "in perpetuity" mitigation options, the mitigation areas will be 
preserved and managed in perpetuity by SCVWD or a land management agency. These 
options will reduce impacts to riparian vegetation to less-than significant levels by directly 
replacing such vegetation (in-kind restoration/creation]; directly improving the functions 
and values of existing riparian vegetation and maintaining those resources through long¬ 
term management (in-kind preservation and enhancement]; or indirectly enhancing 
and/or protecting riparian functions and values by protecting watershed lands that 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-79 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


contribute to riparian habitat ecology and integrity (out-of-kind preservation of watershed 
lands]. The mitigation ratios for these three options were selected to reflect the relative 
value of each type of mitigation, with in-kind restoration/creation having the lowest 
mitigation ratio to reflect its direct compensation for lost riparian vegetation, and out-of¬ 
kind preservation of watershed lands having the highest mitigation ratio to reflect its more 
indirect value in protecting and enhancing riparian vegetation. Because acquisition lands 
will be conserved in perpetuity, the mitigation they provide also will serve the SMP in 
perpetuity. As a result, if in-perpetuity mitigation is applied to impacts to riparian 
vegetation in a certain area, no further mitigation will be needed if repetitive impacts to 
that area occurs, in perpetuity. 

"Pay as you go" mitigation via invasive plant management and riparian planting will 
directly compensate for impacts to riparian vegetation. In many areas, invasive plant 
management will remove invasive species that occupy areas that otherwise can support 
riparian vegetation, and that threaten further to invade riparian areas. Riparian planting 
obviously will provide in-kind mitigation for impacts to riparian vegetation. 

Mitigation for bank stabilization impacts also will be provided, as described in Mitigation 
Measure BIO-1 for wetlands and other waters. 

Two components of the mitigation package that are directly applicable to the 
compensation for impacts to riparian vegetation, but that were not applicable to (and thus 
not discussed in] Mitigation Measure BIO-1, are mitigation for pruning and mitigation for 
removal of trees 6-12 inches dbh (removal of trees greater than 12 inches dbh is not 
included in the SMP], 

The mitigation requirement for pruning is the same as the riparian replanting mitigation 
ratio of 1.2:1. Based on the International Society of Arboriculture pruning standards, and 
the SMP Manual (Appendix A], no more than 25 percent of a tree would be pruned, unless 
greater pruning is necessary for safety or specific ecological purposes (e.g., codominant 
stem species]. Applying the degree of impact (25 percent of any given tree] to the 
mitigation ratio of 1.2:1, the resulting mitigation factor is 0.3. Up to 40 acres of pruning 
may occur, and thus the resulting mitigation acreage necessary is 12 acres (40 acres x 0.3], 
Whereas other mitigation will be calculated on an annual basis, these 12 acres of 
mitigation will be provided for the entire program, and a maximum (or "cap"] of 40 acres 
of hand pruning will be established for the entire program for the period 2012-2022. 

Removal of trees up to 6 inches dbh will not require mitigation on a tree-by-tree basis; 
rather, impacts to woody riparian vegetation comprised of trees or shrubs less than 6 
inches dbh will be mitigated (as described above] via in perpetuity or pay as you go 
mitigation. However, removal of trees sized 6-12 inches dbh will be mitigated through the 
individual planting of replacement trees. Appendix B in the 2012-2022 SMP Update 
Mitigation Approach Memorandum (Appendix C], Tree Scoring for Removal of Trees and 
Shrubs < 12"DBH provides a specific tree appraisal and evaluation protocol to determine 
how replacement planting occurs. The protocol involves carefully assessing targeted tree 
removals for their existing conditions and functions, including their canopy cover, local 
area value, ecosystem benefits, and ecosystem detriments. Using a cumulative ranking 
method, tree replacement mitigation ratios for removed trees (6-12 inches dbh] occurs at 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-80 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


either 1:1, 2:1, or 3:1 (replacement tree to removed tree], depending on the overall quality 
and function of the removed tree. 

Impacts to riparian vegetation containing trees 6-12 inches dbh are, therefore, mitigated in 
two ways—mitigation on an acreage basis via in perpetuity or pay as you go mitigation, 
plus mitigation via replacement of trees 6-12 inches dbh. The two mitigation areas will be 
non-overlapping. As a result, the extent of mitigation for impacts to more mature woody 
riparian vegetation will be greater, as is appropriate based on the greater functions and 
values to wildlife, than impacts to less mature riparian vegetation. 

As part of the riparian mitigation component, SCVWD will mitigate impacts to sensitive 
riparian communities, including sycamore alluvial woodland and oak woodland, in-kind. 
For a specific extent of impact to sycamore alluvial woodland or oak woodland, the in 
perpetuity or pay as you go mitigation that is applied to that impact will focus on 
enhancement, preservation, and/or restoration of that sensitive community type; removal 
of invasives will not be considered appropriate mitigation for these sensitive community 
types unless accompanied by restoration that targets that community type. Similarly, when 
impacts to high-quality occurrences of cottonwood-dominated forest occur, SCVWD will 
mitigate by providing cottonwood-dominated mitigation sites. "High-quality" occurrences 
will be determined by a qualified botanist based on criteria such as evidence of natural 
regeneration and the presence of multi-layered and multi-aged stands. 

It is possible that these mitigation measures may be refined during permitting with the 
USACE, RWQCB, and CDFG, in which case the refinements required by these resource 
agencies would be implemented. 

MM BIO-2 will mitigate impacts to riparian habitats to less-than-significant levels by 
replacing lost riparian vegetation through restoration or by replacing the lost functions 
and values provided by these habitats through other means, such as non-native plant 
removal and watershed protection. Thus, MM BIO-2 will assure that the SMP does not 
result in a substantial adverse effect on sensitive riparian communities. 

Impact BIOS: Disturbance of Sensitive Plant Communities 
(Significance Criteria A and D; Less than Significant with Mitigation) 

Sensitive plant communities (see Regulated and Sensitive Natural Communities above] 
often are of limited distribution within a region and frequently support special-status 
species or high numbers of common species. Thus, the conservation of these natural 
communities is integral to maintaining biological diversity. However, as described above 
under Determination of Impacts on Aquatic and Wetland Communities and Determination of 
Impacts on Non-instream Sensitive Plant Communities, Proposed Project activities may 
affect sensitive plant communities through direct disturbance of vegetation and 
disturbance, modification, or destruction of habitat. Impacts to wetlands and aquatic 
habitats in general, which are considered sensitive communities, are described under 
Impact BIO-1, and impacts to riparian habitats (also sensitive communities] are described 
under Impact BIO-2. Impact BIO-3 focuses on specific sensitive communities, such as 
northern coastal salt marsh, sycamore alluvial woodland, and serpentine communities. 
Table 3.3-10 summarizes estimated impacts of projected SMP Update activities on these 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-81 


December 2011 
Project No. 10.005 


3.3 Biological Resources 


latter communities, based on mapping by AIS and SCVWD projections for maintenance 
activities during the period 2012-2022. 

Table 3.3-10. Estimated Impacts to Northern Coastal Salt Marsh. Sycamore 
Alluvial Woodland, and Serpentine Communities from Projected SMP Update 
Activities, 2012-2022 


Community 

Projected Imoact 
(acres] 

Northern Coastal Salt Marsh 

83 

Svcamore Alluvial Woodland 

17.6 

Coast Live Oak 

27.3 

Valiev Oak 

12 

Serpentine 

24.4 


Note: 

Source: Data compiled by Horizon Water and Environment in 2011 based on information 
from SCVWD and AIS. 


Northern coastal salt marsh would not be directly impacted by sediment removal, but 
vegetation management in 8.3 acres of salt and brackish marsh habitats would affect these 
habitats. Some vegetation management would result in temporary degradation of northern 
coastal salt marsh communities via mowing or removal of plants, which would affect the 
structure of this community and the services it would provide to wildlife. Impacts to this 
community would be as described under Impact BIO-1 for wetland and aquatic habitats. 
However, the majority of such impacts (6.8 acres] would occur as a result of herbicide 
application in perennial pepperweed-dominated areas near Coyote Slough and Coyote 
Bypass. This activity, which occurs in part as mitigation for impacts resulting from the 
Lower Coyote Creek capital project, would enhance habitat conditions by reducing the 
infestation of salt marsh by the invasive perennial pepperweed. 

No activities are projected within the highest-quality occurrences of sycamore alluvial 
woodland, such as those along Coyote Creek from U.S. Highway 101 downstream to the 
Ogier Ponds, or along Pacheco Creek. However, vegetation management activities are 
projected in 17.6 acres mapped as sycamore-dominated by AIS. More than half of this 
impact would occur in the Guadalupe River watershed. Impacts to this community would 
occur in the same ways as described under Impact BIO-2 for impacts to woody riparian 
vegetation. 

Impacts to oak woodland communities would occur in a number of locations where the 
streamside vegetation is dominated by oaks. Approximately 23.4 acres dominated by coast 
live oak and 3.1 acres dominated by valley oak would be impacted by projected vegetation 
management activities in the Santa Clara Basin, while 3.9 acres dominated by coast live oak 
and 4.1 acres dominated by valley oak would be impacted by projected vegetation 
management activities in the Pajaro Basin. Impacts to this community would occur in the 
same ways as described under Impact BIO-2 for impacts to woody riparian vegetation. 

Projected activities would occur in or very close to serpentine communities, primarily 
along portions of the Coyote Canal, Coyote Canal Extension, Coyote Alamitos Canal, and 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-82 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Almaden Calero Canal, where high-quality serpentine communities were mapped by 
SCVWD botanist J. Hillman based on surveys in 2004 and 2008 (Figure 3.3-2], Although 
serpentine communities likely would occur near work sites elsewhere, such as along 
Upper Silver Creek, no high-quality serpentine communities were identified in these areas 
during SCVWD's surveys. As described under Determination of Impacts to Non-instream 
Sensitive Plant Communities above, proposed maintenance activities could result in a 
variety of impacts on serpentine communities. For example, during any bank stabilization, 
sediment removal, vegetation management, and animal conflict management activity that 
would occur in or adjacent to serpentine, equipment use, vehicle traffic, and worker foot 
traffic may result in the injury or mortality of individual plants. These activities could 
result in death, altered growth, or reduced seed set through physically breaking, crushing, 
wilting, or uprooting plants, and the compaction of soil by heavy equipment could damage 
plant roots. In addition, vegetation management activities and the creation of access routes 
and staging areas may result in the mechanical or physical removal of vegetation as a 
result of off-target herbicide contact via drift. Although such impacts would be temporary 
in that they would not preclude the regeneration of serpentine vegetation, the repetitive 
nature of impacts in at least some areas would result in longer-term effects over the 10- 
year duration of the SMP Update. Permanent impacts to serpentine communities may 
occur if bank stabilization activities were necessary in such areas. Unprojected activities 
(e.g., bank stabilization, management of animal conflicts, and minor maintenance] also 
could result in the loss or disturbance of serpentine communities. 

For the sake of estimating the extent of potential impacts to serpentine plant communities, 
all projected activities along canals that were determined to provide high-quality 
serpentine communities, as depicted in Figure 3.3-2, were evaluated. These activities are 
projected to impact up to 5.04 linear miles of Coyote, Coyote Extension, Coyote Alamitos, 
and Almaden Calero Canals within high-quality serpentine communities. Assuming 
(conservatively] that areas up to 20 feet on either side of the canal could be impacted, 
projected activities could impact up to 24.43 acres of high-quality serpentine communities. 

SCVWD would implement several measures to address the impacts of Proposed Project 
activities on sensitive plant communities, including pre-project planning BMPs to minimize 
the area of disturbance and pre-activity surveys to identify and avoid sensitive plant 
communities. These BMPs are listed below, and descriptions of each are provided in 
Table 2-12. 

Applicable Best Management Practices 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-9: Avoid Impacts to Special-Status Plant Species and Sensitive Natural 

Vegetation Communities 

BMP GEN-21: Staging and Stockpiling of Materials 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-83 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Conclusion 

Implementation of these BMPs would minimize disturbance of sensitive plant 
communities. Nevertheless, the Proposed Project would result in temporal losses of 
functions and values, and possibly some permanent losses of sensitive plant communities 
because complete avoidance could not be accomplished while still meeting the project 
goals for public health and safety directives. Thus, residual impacts would remain. 
Although most of the impacts to northern coastal salt marsh would result from beneficial 
activities (invasive species management], and impacts to sycamore-dominated habitat 
would not strictly be to typical sycamore alluvial woodland communities, both impacts 
would be significant because of the value of these communities to wildlife (Significance 
Criteria A and D). Impacts to serpentine communities, because of the importance of these 
communities to special-status species and their regional rarity, and to oak woodlands, 
because of their ecological importance to a diversity of riparian and upland wildlife 
species, would be significant (Significance Criteria A and D). 

No mitigation would be required for vegetation management that was specifically 
performed for ecologically beneficial purposes; for example, management of the invasive 
perennial pepperweed in the Coyote Creek Bypass area would benefit the northern coastal 
salt marsh community, and thus it would not require mitigation. As noted under Mitigation 
Measure BIO-1, e xc e ss mitigation provided by restoration of tidal habitats at the Island 
Ponds under the 2002-2012 SMP also would compensate for impacts of 2012-2022 
Proposed Project activities on tidal wetlands, such as northern coastal salt marsh. 
Therefore, implementation of Mitigation Measure BIO-1 would reduce Proposed Project 
impacts to northern coastal salt marsh communities to less-than-significant levels. 

Implementation of Mitigation Measure BIO-2 would reduce residual impacts to sycamore 
alluvial woodland/oak woodland and serpentine communities, respectively, to a less-than- 
significant level by implementing applicable components of the mitigation package with a 
direct focus on mitigation specific to these two community types whenever impacts to 
these communities occurred. 

Mitigation Measure BIO-3 would be implemented to reduce impacts to sensitive plant 
communities to a less-than-significant level. 

Mitigation Measure BIOS: Implement Compensatory Mitigation for Serpentine 
Communities 

SCVWD will provide mitigation for unavoidable impacts to high-quality serpentine 
communities, including grassland, rock outcrops, seeps, and chaparral. SCVWD would 
refine the quantification of impacts to high-quality serpentine habitat on an annual basis. 
Along SCVWD's canals, where most or all SMP impacts to serpentine species and 
communities are expected to occur, high-quality serpentine communities were mapped by 
SCVWD using data gathered during surveys in 2004 and 2008. Serpentine communities are 
considered to be of “high quality" if they are in a semi-natural or natural/undisturbed state 
and meet one or both of the following criteria: 

■ Presence of multiple special-status plant occurrences 

■ Relatively high abundance of natives or serpentine obligates vs. non-natives 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-84 


December 2011 
Project No. 10.005 



N:\Projects3000\3166-01\Reports\EIR June 2011 


Santa Cruz County 


LEGEND 

Santa Clara County Boundary 
SMP Project Area 
SMP Creeks and Canals 
Mapped Serpentine Soils 
Additional Potential Serpentine Communities 
High-Quality Serpentine Communities in Projected SMP Work Areas 
New Sediment Removal, 2012-2022 
Sediment Removal, both 2002-2012 and 2012-2022 
New Vegetation Management, 2012-2022 

Vegetation Management, both 2002-2012 and 2012-2022 

Note: Project area maps provide a general description of work type and area for 
the 2012-2022 SMP and are not intended to represent the exact locations of 
future work. 




V 


0 

N _ 

5,000 10,000 


A ^ 

1 1 

0 

1 2 Miles 





H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-2: Projected SMP Update Activities in Serpentine Communities 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 
























This page intentionally left blank. 



3.3 Biological Resources 


Before Proposed Project activities that can impact serpentine communities and species, an 
SCVWD botanist will conduct a review of potential serpentine impact areas using existing 
data, such as SCVWD's mapping, and field verification as needed, to identify high-quality 
serpentine communities. At the end of that year's maintenance period, SCVWD will 
determine the extent of impacts to high-quality serpentine communities that have 
occurred during the year. 

Compensation for unavoidable effects to high-quality serpentine communities will be 
provided via the protection, enhancement, and management of serpentine communities 
outside SMP work sites at a 2:1 f mitigation: impact :mitigation l ratio, on an acreage basis. 
SCVWD will acquire land supporting serpentine communities via fee title or purchase of a 
conservation easement. Compensatory mitigation may be carried out through one or both 
of the following methods, in order of preference: 

■ The preservation and management of existing serpentine communities 

■ The restoration or enhancement of previously existing or degraded 
serpentine communities 

SCVWD will develop a Habitat Mitigation and Management Plan (HMMP], describing the 
measures that will be taken to enhance and manage the mitigation lands and to monitor 
the effects of management on serpentine communities. That plan will include, at a 
minimum, the following: 

» A summary of impacts to high-quality serpentine communities and the 
proposed mitigation 

■ A description of the location and boundaries of the mitigation site and 
description of existing site conditions 

■ A description of measures to be undertaken if necessary to enhance (e.g., 
through focused management] the mitigation site for serpentine 
communities 

■ Proposed management activities, such as managed grazing and management 
of invasive plants, to maintain high-quality serpentine communities 

■ A description of community monitoring measures on the mitigation site, 
including specific, objective goals and objectives fincluding maintaining or 
increasing native plant species diversity! performance indicators and 
success criteria fincluding maintaining or increasing the relative abundance 
of native vs. non-native species], monitoring methods fincluding vegetation 
sampling for plant species composition! data analysis, reporting 
requirements, and monitoring schedule 

(Determining other specific performance/success criteria requires 
information regarding the specific mitigation site, its conditions, the 
biological resources present on the site, and the specific enhancement and 
management measures tailored to that site and its conditions. As a result, 
additional these specific criteria will be defined in the HMMP rather than in 
this SEIR. Nevertheless, the performance/success criteria described in the 
HMMP will guide the mitigation for management and protection of high- 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-85 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


quality serpentine communities to adequately compensate for the functions 
and values of the impacted communities.] 

» A description of the management plan's adaptive component, including 
potential contingency measures for mitigation elements that do not meet 
performance criteria 

■ A description of the funding mechanism for the long-term maintenance and 
monitoring of the mitigation lands 

After mitigation has been provided for impacts to a specific area supporting high-quality 
serpentine communities and/or special-status species from a specific year's activities, 
future (i.e., repetitive] impacts to that area will not require additional mitigation. 

The HMMP will be provided to the USFWS for review because some of the serpentine- 
associated special-status species that would benefit from this mitigation are federally 
listed species regulated by the USFWS. It is possible that this mitigation measure may be 
refined during the Section 7 consultation process with the USFWS (e.g., in the Biological 
Opinion covering Project effects on federally listed, serpentine-associated species], in 
which case the refinements required by the USFWS would be implemented. 

MM BIO-3 will mitigate impacts to sensitive serpentine communities to less-than- 
significant levels by replacing the functions and values provided by such communities 
through the enhancement, management, and protection of serpentine communities. Thus, 
MM BIO-3 will assure that the SMP does not result in a substantial adverse effect on 
sensitive serpentine communities or threaten to eliminate this plant community. 

Impact BIO-4: Impacts to Serpentine-Associated Special-Status Plant Species 
(Significance Criteria A and B; Less than Significant with Mitigation) 

Serpentine plant communities in the Project Area support a unique assemblage of plant 
species, including the following special-status species (see Figure 3.3-3 and Table 3.3- 
202JJ: 

■ Tiburon paintbrush 

■ Coyote ceanothus 

■ Santa Clara Valley dudleya 

■ Metcalf Canyon jewel-flower 

■ Big-scale balsamroot 

■ Pink creamsacs 

» Mt. Hamilton thistle 

■ Fragrant fritillary (Fritillaria falcata) 

■ Woolly-headed lessingia ( Lessingia hololeuca ] 

■ Smooth lessingia ( Lessingia micradenia var. glabrata ] 

■ Most beautiful jewel-flower ( Streptanthus albidus ssp. peramoenus ] 

Neither the Tiburon paintbrush nor Coyote ceanothus are known to occur in or very close 
to areas where activities are either projected or expected to occur, and because of the 
intensity of survey effort for these species over the years, both on SCVWD facilities and in 
general, a previously unknown occurrence is not expected to be located in an area where it 
could be affected by Proposed Project activities. However, the possibility of colonization of 
serpentine habitat in or near the Coyote, Coyote Extension, Coyote Alamitos, or Almaden 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-86 


December 2011 
Project No. 10.005 




N:\Projects3000\3166-01\Reports\EIR June 2011 



LEGEND 


Santa Clara County Boundary 


SMP Project Area 


SMP Creeks and Canals 


Mapped Serpentine Soils 


Additional Potential Serpentine Communities 

Known Locations of Special-Status Serpentine 
Plants (CNDDB and SCVWD Records) 


2 Miles 


-Associated 


\ 




H. T. HARVEY & ASSOCIATES 


Figure 3.3-3: Mapped Serpentine Soils and Known Locations of Special-Status Serpentine-Associated Plants 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 


ECOLOGICAL CONSULTANTS 














































This page intentionally left blank. 



3.3 Biological Resources 


Calero canals cannot be eliminated. Thus, because Tiburon paintbrush and Coyote 
ceanothus are so rare that any new occurrence would be significant to the population, and 
any loss of individuals or degradation of the health of the population would result in a 
substantial adverse effect on the species, SCVWD would implement BMP GEN-9 ( Avoid 
Impacts to Special-Status Plant Species and Sensitive Natural Vegetation Communities ] to 
prevent all direct and indirect effects on these species. Individuals of these species would 
be sought during pre-activity surveys along the segments of the aforementioned canals 
that are located within serpentine communities and, if any individuals were found, 
Proposed Project activities would be modified to prevent adverse effects on them. Thus, 
with implementation of BMPs, no short- or long-term effects on the Tiburon paintbrush 
and Coyote ceanothus are expected to occur. 

Several of the special-status plants listed above are known to occur in or near proposed 
work sites. During SCVWD's 2004 and 2008 surveys of SMP channels within serpentine 
communities, both the federally listed Santa Clara Valley dudleya and Metcalf Canyon 
jewel-flower were documented within SCVWD canal easement (Figure 3.3-3], Santa Clara 
Valley dudleya was documented along the Coyote Alamitos Canal, the Coyote Canal 
Extension, and the Almaden Calero Canal. One population of Metcalf Canyon jewel-flower 
was documented along the Coyote Canal Extension. Other special-status serpentine- 
associated plant species located in SMP work sites during SCVWD's 2004 and 2008 surveys 
included Mt. Hamilton thistle, smooth lessingia, Hall’s bush-mallow, and most beautiful 
jewel-flower. Although none of the remaining serpentine-associated species listed above 
were detected during these surveys, serpentine soils similar to those that support known 
populations occur in the Project Area throughout much of Coyote Ridge, on Tulare Hill, and 
in the Santa Teresa Hills. Thus, some potential would exist to find serpentine bunchgrass 
grassland, rock outcrops, seeps, and mixed serpentine chaparral habitat virtually 
anywhere in the Project Area that may support these species. 

As was discussed for serpentine communities under Impact BIO-3, projected activities 
would occur in or very close to serpentine communities primarily along portions of the 
Coyote Canal, Coyote Canal Extension, Coyote Alamitos Canal, and Almaden Calero Canal 
where high-quality serpentine communities were mapped by SCVWD botanist J. Hillman, 
based on surveys in 2004 and 2008 (Figure 3.3-2], 

Although serpentine communities occurred near SMP work sites elsewhere, such as along 
Upper Silver Creek, no high-quality serpentine communities were identified in these areas 
during SCVWD's surveys. As described under Determination of Impacts to Special-Status 
Plants, proposed maintenance activities could result in a variety of short-term impacts on 
serpentine-associated special-status plants. For example, during any bank stabilization, 
sediment removal, vegetation management, and animal conflict management activity that 
occurred in or adjacent to serpentine communities, equipment use, vehicle traffic, and 
worker foot traffic may result in the injury or mortality of individual plants. These 
activities could result in death, altered growth, or reduced seed set by the physical 
breaking, crushing, wilting, or uprooting of plants, and soil compaction by heavy 
equipment could damage plant roots. In addition, vegetation management activities and 
the creation of access routes and staging areas may result in the mechanical or physical 
removal of special-status plants and the damage or mortality of individuals as a result of 
off-target herbicide contact via drift. Although such impacts to habitat of these species 
would be temporary in that they would not preclude the regeneration of serpentine 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-87 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


vegetation and the recolonization of these areas by special-status plants, the repetitive 
nature of impacts in at least some would result in longer-term effects over the 10-year 
duration of the SMP Update. Permanent impacts to serpentine-associated special-status 
plants may occur if bank stabilization activities were necessary in occupied habitat. 
Unprojected activities (e.g., bank stabilization, management of animal conflicts, and minor 
maintenance] also could result in the loss or disturbance of serpentine-associated special- 
status plant populations. 

As discussed for serpentine communities under Impact BIO-3, SMP Update activities are 
projected to impact up to 5.04 linear miles of canal within high-quality serpentine 
communities. Assuming (conservatively] that areas up to 20 ft on either side of the canal 
could be impacted, projected activities could impact up to 24.43 ac of high-quality 
serpentine communities. Although special-status serpentine-associated plants occur in 
only a subset of this area, there is some potential for impacts to populations of these 
species throughout that area. 

SCVWD would implement several measures to address the impact of Proposed Project 
activities, including pre-project planning BMPs to minimize the area of disturbance. 
Implementation of the BMP specifically designed to protect special-status plants (BMP 
GEN-9] would avoid or minimize impacts to these species through the identification and 
avoidance of serpentine and serpentine-associated special-status species. These BMPs are 
as follows, and a description of each is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-9: Avoid Impacts to Special-Status Plant Species and Sensitive Natural 

Vegetation Communities 

BMP GEN-21: Staging and Stockpiling of Materials 
Conclusion 

By implementing these BMPs, SCVWD would reduce impacts to serpentine-associated 
special-status plant species. However, complete avoidance of special-status serpentine- 
associated plant species would be infeasible. Impacts would most likely occur if special- 
status serpentine plants were located within a levee road or on a canal bank between the 
access road and the canal, if sediment on which Mt. Hamilton thistle was growing needed 
to be removed, or if unprojected maintenance activities occurred in areas where avoidance 
of serpentine habitats and species was not feasible. If impacts to special-status serpentine 
plants was unavoidable, such impacts would be significant because of their regional rarity 
(Significance Criteria A and B], Mitigation Measure BIO-4 would be implemented to 
provide compensation for these impacts, reducing the impact on serpentine-associated 
special-status plant species to a less-than-significant level. 

Implementation of Mitigation Measure BIO-3 for serpentine plant communities would help 
to reduce impacts to special-status serpentine-associated plants by providing 
compensation for impacts to high-quality occurrences of communities in which these 
special-status species occurred. However, Mitigation Measure BIO-4 still would be 
necessary so that mitigation specific to the impacted species was provided. Mitigation 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-88 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Measure BIO-4 would be implemented to reduce the impact to serpentine-associated 
special-status plant species to a less-than-significant level. 

Mitigation Measure BIO-4: Implement Compensatory Mitigation for Serpentine- 
Associated Special-Status Plant Species 

SCVWD will provide mitigation for unavoidable impacts to serpentine-associated special- 
status plant populations. Before Proposed Project activities that can impact serpentine 
communities and species, an SCVWD botanist will conduct a review of potential serpentine 
impact areas using existing data, such as SCVWD's mapping, and field verification as 
needed, to identify high-quality serpentine communities. The botanist also will conduct a 
pre-activity survey for special-status plants. At the end of that year's maintenance period, 
SCVWD would refine the quantification of impacts to populations of special-status 
serpentine-associated plants. 

Compensation for unavoidable impacts to populations of special-status serpentine-associated 
plants will be provided by a combination of preservation and enhancement of those species’ 
populations outside SMP work sites. For impacts to populations (including partial populations) 
of a specific special-status serpentine plant species, compensatory mitigation will include 
preservation, enhancement, and management of lands that (a) already support equal or greater 
numbers (and health) of individuals of that species and (b) contain sufficient unoccupied habitat 
to allow for an increase in populations, the increase being at least equivalent to the number 
impacted, through habitat enhancement and management. For determining the number of 
individuals impacted, the highest number of individuals known to be present within the impact 
area (if the impact area has undergone multiple surveys) will be used to determine the magnitude 
of the impact. 

Compensatory mitigation for impacts to high-quality serpentine communities (as 
discussed in Mitigation Measure BIO-3) and special-status serpentine-associated plants 
may occur on the same lands, provided that the conditions pertaining to special-status 
plant species are satisfied for each species for which mitigation is required. The HMMP 
that will be prepared by SCVWD to describe the measures that will be taken to enhance, 
manage, and monitor the mitigation lands (as discussed in Mitigation Measure BIO-3) also 
will include consideration of focal special-status species. For example, in addition to the 
measures described in Mitigation Measure BIO-3, the HMMP also will include the 
following: 

■ A summary of impacts to special-status plant populations and the proposed 
mitigation 

■ A description of measures to be undertaken if necessary to enhance (e.g., 
through focused management) the mitigation site for special-status species 

■ A description of measures to transplant individual plants or seeds from the 
impact area to the mitigation site, if determined by a qualified botanist to be 
appropriate and to have a high likelihood of success 

■ Proposed management activities, such as managed grazing and management 
of invasive plants, to maintain high-quality habitat conditions for the focal 
species 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-89 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


■ A description of species monitoring measures on the mitigation site, 
including specific, objective goals and objectives (including enhancement of 
populations of focal special-status species on the mitigation site], 
performance indicators and success criteria (including increasing the 
abundance of the focal species by at least as many individuals as were 
impacted], monitoring methods (including sampling for the focal species], 
data analysis, reporting requirements, and monitoring schedule. 

Determining other specific performance/success criteria requires 
information regarding the specific mitigation site, its conditions, the 
biological resources present on the site, the specific plant species for which 
mitigation is being provided, and the specific enhancement and management 
measures tailored to the mitigation site and its conditions. As a result, 
additional specific criteria will be defined in the HMMP rather than in this 
SEIR. Nevertheless, the performance/success criteria described in the 
HMMP will guide mitigation to manage and protect high-quality serpentine 
habitat for, and populations of, the impacted species. The HMMP will include 
monitoring for non-native plant species and remediation measures in the 
event that such species are detected on the site. 

After mitigation has been provided for impacts to special-status plant populations in a 
specific area from a specific year's activities, future (i.e., repetitive] impacts to that area 
will not require additional mitigation. 

The HMMP will be provided to the USFWS for review because some of the serpentine- 
associated special-status species for which the HMMP will be prepared are federally listed 
species regulated by the USFWS. It is possible that this mitigation measure may be refined 
during the Section 7 consultation process with the USFWS (e.g., in the Biological Opinion 
covering Project effects on federally listed, serpentine-associated species], in which case 
the refinements required by the USFWS would be implemented. 

MM BIO-4 will mitigate impacts to special-status serpentine-associated plants to less-than- 
significant levels by enhancing, managing, and protecting populations of these species so 
that the SMP does not substantially reduce the number or restrict the range of rare or 
endangered serpentine-associated plants or have a substantial adverse effect on special- 
status serpentine-associated plants. 

Impact BIOS: Impacts to NonSerpentine SpecialStatus Plant Species 
(Significance Criteria A and B; Less than Significant with Mitigation) 

Special-status plants, typically not strongly associated with serpentine communities and 
instead typically occurring in communities such as valley and foothill grassland and 
riparian woodland, are present in the Project Area (see Figure 3.3-4 and Table 3.3-2021]. 
Thus, maintenance activities involving the removal of upland vegetation or ground 
disturbance could have impacts on the following special-status plant species: 

■ Franciscan onion ( Allium peninsulare var.franciscanum ] 

■ Bent-flowered fiddleneck ( Amsinckia lunaris ] 

■ Anderson's manzanita ( Arctostaphylos andersonii ] 

■ Brittlescale ( Atriplex depressa ] 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-90 


December 2011 
Project No. 10.005 



N:\Projects3000\3166-01\Reports\EIR June 2011 


Alameda County 



,it enc/a 


County 


San Joaquin 
County 


Santa Cruz County 


San Benito County 


Monterey County 


Pacific Ocean 


Merced County 


• Specific Location 
Approximate Location 
General Area 


LEGEND 

| | Santa Clara County Boundary 

SMP Project Area 

Known Locations of Non-serpentine Special-Status Plants 
(CNDDB and SCVWD Records) 




H. T. HARVEY & ASSOCIATES 


ECOLOGICAL CONSULTANTS 


Figure 3.3-4: Known Locations of Non-serpentine Special-Status Plants 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 
















































This page intentionally left blank. 



3.3 Biological Resources 


* Round-leaved fdaree (Erodium macrophyllum] 

■ Congdon's tarplant (Hemizonia parryi ssp. congdonii ] 

■ Santa Clara red ribbons (Clarkia concinna ssp. automixa) 

» Hospital Canyon larkspur (Delphinium californicum ssp. interius ] 

■ Western leatherwood [Dirca occidentalism 

■ Hoover's button-celery [Eryngium aristulatum var. hooveri ] 

■ Satan's goldenbush (Isocoma menziesii var. diabolica) 

* Showy golden madia (Madia radiata) 

■ Davidson's bush-mallow (Malacothamnus davidsonii ] 

■ Hall’s bush-mallow (Malacothamnus hallii ] 

■ Loma Prieta hoita [Hoita strobilina) 

■ San Francisco collinsia (Collinsia multicolor] 

■ Oregon meconella (Meconella oregana] 

■ Mt. Diablo cottonweed (Micropus amphibolus] 

■ Robust monardella (Monardella villosa ssp. globosa) 

» Hooked popcorn-flower (Plagiobothrys uncinatus) 

■ Saline clover (Trifolium depauperatum var. hydrophilum] 

As discussed under Determination of Impacts to Special-Status Plants, proposed 
maintenance activities may result in direct and indirect impacts on these species as a 
result of trampling by personnel and equipment; soil compaction leading to damage of 
roots; or alteration of hydrology and mechanical, physical, or chemical removal of 
vegetation. Because these species generally are not associated with a single vegetation or 
soil type, as is the case with the serpentine-associated special-status species considered 
under Impact BIO-4, site-specific impacts to these species resulting from Proposed Project 
activities are difficult to predict. However, each of the species listed above has some 
potential to occur in areas where they could be adversely affected by Proposed Project 
activities. 

Santa Clara red ribbons, Hospital Canyon larkspur, and robust monardella are each known 
from numerous reported occurrences in the Project Area. However, these upland species 
are expected to occur infrequently and in low numbers in riparian areas where Proposed 
Project activities would be focused. Thus, the Proposed Project likely would have an 
adverse affect on only a very small proportion of the regional populations of these species, 
and possibly most of these species would not be affected at all. Because the effects of 
maintenance activities are not expected to rise to the threshold of a substantial adverse 
effect on regional populations, Proposed Project impacts to these species will be less than 
significant. 

Round-leaved fdaree, Congdon's tarplant, Hoover's button-celery, Satan's goldenbush, 
showy golden madia, San Francisco collinsia, western leatherwood, and Mt. Diablo 
cottonweed are each known from only a few locations in the Project Area. As a result, little 
potential would exist for impacts to these species. However, any impacts on these species 
as a result of the Proposed Project may result in a substantial effect on the species' regional 
populations because of their greater rarity in the region, compared to the species 
discussed in the previous paragraph. Thus, this impact would be significant (Significance 
Criterion B}. In addition, Hall’s bush mallow is known to occur on the Coyote Canal 
Extension within an SMP work site. During surveys by SCVWD botanists in 2004 and 2008, 
four occurrences totaling up to 55 individuals were recorded. Canal maintenance, 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-91 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


particularly vegetation management, could result in the loss of these individuals. Because 
of the regional rarity and relatively low number of regional occurrences of Hall's bush 
mallow, this impact would be significant. 

Occurrences of Franciscan onion, bent-flowered fiddleneck, Anderson's manzanita, 
brittlescale, hooked popcorn flower, Oregon meconella, and saline clover are unknown in 
the Project Area. However, suitable habitat for these species is present and, because of the 
lack of comprehensive surveys of all SMP work sites (which would be infeasible because of 
the extent of the Project], the possibility of occurrence of these species within a work site 
could not be dismissed. Because these species have not been recorded in the Project Area, 
possibly they would not be impacted at all. Nevertheless, any impacts to newly discovered 
populations of these species in the Project Area would be considered significant, as the 
population would represent an extension of the species' known distribution (Significance 
Criteria A and B], Similarly, Davidson's bush-mallow is known from the Project Area only, 
from three historical records dating back to 1936. Thus, any impacts to newly discovered 
populations of this species in the Project Area would be considered significant 
(Significance Criteria A and B], 

SCVWD would implement pre-project planning BMPs, including limiting impacts to the 
minimum area required, to address the impact of Proposed Project activities on non¬ 
serpentine special-status plant species. In addition, implementation of the BMP specifically 
designed to protect special-status plants and sensitive communities would avoid impacts 
to these species through the identification and avoidance of occupied habitat. These BMPs 
are as follows, and a description of each is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-9: Avoid Impacts to Special-Status Plant Species and Sensitive Natural 

Vegetation Communities 

Conclusion 

By implementing these BMPs, SCVWD would reduce impacts to non-serpentine special- 
status plants by avoiding both direct and indirect impacts to these species. However, 
circumstances may arise in which complete avoidance of special-status plants was 
infeasible. For example, unprojected maintenance activities may need to occur in areas 
where avoidance of occurrences was infeasible because complete avoidance could not be 
accomplished while still meeting the project goals for public health and safety directives. If 
impacts to populations or partial populations of the round-leaved filaree, Congdon's 
tarplant, Hoover's button-celery, Satan's goldenbush, showy golden madia, Davidson's 
bush-mallow, Mt. Diablo cottonweed, Franciscan onion, bent-flowered fiddleneck, 
Anderson's manzanita, brittlescale, hooked popcorn flower, Hall's bush mallow, Oregon 
meconella, or saline clover were unavoidable, such impacts would be significant 
(Significance Criteria A and B], 

Mitigation Measure BIO-5 would be implemented to reduce impacts to non-serpentine 
special-status plant species to a less-than-significant level. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-92 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Mitigation Measure BIO-5: Implement Compensatory Mitigation for Impacts to 
Non-Serpentine Special-Status Plant Species 

If Proposed Project activities result in the loss of individual non-serpentine special-status 
plants, other than the Santa Clara red ribbons, Hospital Canyon larkspur, western 
leatherwood, Hall’s bush-mallow, and robust Monardella, compensatory mitigation will be 
provided. Before Proposed Project activities that can impact these special-status species, 
an SCVWD botanist will conduct a review of potential impact areas using existing data, and 
field verification as needed, to identify areas of potential occurrence of these species. The 
botanist also will conduct a pre-activity survey for special-status plants in areas where 
occurrence is possible. At the end of that year's maintenance period, SCVWD will 
determine the extent of impacts to populations of these special-status plants. 

Compensation for unavoidable impacts to populations of special-status non-serpentine 
plants will be provided by a combination of preservation and enhancement of those 
species' populations outside SMP work sites. For impacts to populations (including partial 
populations] of a specific special-status plant species, compensatory mitigation will 
include preservation, enhancement, and management of lands that [a] already support 
equal or greater numbers (and health] of individuals of that species and (b] contain 
sufficient unoccupied habitat to allow for an increase in populations, the increase being at 
least equivalent to the number impacted, through habitat enhancement and management. 
For determining the number of individuals impacted, the highest number of individuals 
known to be present within the impact area (if the impact area has undergone multiple 
surveys] will be used to determine the magnitude of the impact. 

SCVWD will develop an HMMP describing the measures that will be taken to enhance and 
manage the mitigation lands and to monitor the effects of management on the focal 
special-status plant species. That plan will include, at a minimum, the following: 

» A summary of impacts to special-status plant populations, and the proposed 
mitigation 

■ A description of the location and boundaries of the mitigation site and 
description of existing site conditions 

■ A description of measures to be undertaken if necessary to enhance (e.g., 
through focused management] the mitigation site for special-status species 

» A description of measures to transplant individual plants or seeds from the 
impact area to the mitigation site, if determined by a qualified botanist to be 
appropriate and to have a high likelihood of success 

■ Proposed management activities to maintain high-quality habitat conditions 
for the focal species 

■ A description of species monitoring measures on the mitigation site, 
including specific, objective goals and objectives fincluding enhancement of 
populations of focal special-status species on the mitigation site! 
performance indicators and success criteria fincluding increasing the 
abundance of the focal species by at least as many individuals as were 
impacted! monitoring methods fincluding sampling for the focal species! 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-93 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


data analysis, reporting requirements, and monitoring schedule. 

Determining other specific performance/success criteria requires 
information regarding the specific mitigation site, its conditions, the 
biological resources present on the site, the specific plant species for which 
mitigation is being provided, and the specific enhancement and management 
measures tailored to the mitigation site and its conditions. As a result, 
additional these specific criteria will be defined in the HMMP rather than in 
this SEIR. Nevertheless, the performance/success criteria described in the 
HMMP will guide the mitigation to manage and protect high-quality habitat 
for, and populations of, the impacted species. The HMMP will include 
monitoring for non-native plant species and remediation measures in the event 
that such species are detected on the site. 

■ A description of the management plan's adaptive component, including 
potential contingency measures for mitigation elements that do not meet 
performance criteria 

■ A description of the funding mechanism for the long-term maintenance and 
monitoring of the mitigation lands 

After mitigation has been provided for impacts to a specific area supporting special-status 
species from a specific year's activities, future (i.e., repetitive] impacts to that area will not 
require additional mitigation. 

MM BIO-5 will mitigate impacts to special-status non-serpentine plants to less-than- 
significant levels by enhancing, managing, and protecting populations of these species so 
that the SMP does not substantially reduce the number or restrict the range of rare or 
endangered non-serpentine plants or have a substantial adverse effect on special-status 
non-serpentine plants. 

Impact BIO-6: Impacts to Serpentine-Associated Special-Status Invertebrates 
(Significance Criteria A and B; Less than Significant with Mitigation) 

Serpentine-associated invertebrate species including the Bay checkerspot butterfly, Horn's 
micro-blind harvestman (Microcina homi), Jung's micro-blind harvestman (Microcina 
jungi ), and Opler's longhorn moth (Adela oplerella ] may be affected by projected activities 
that occurred along canals running through serpentine habitats. As was discussed for 
serpentine communities under Impact BIO-3, projected activities would occur in or very 
close to serpentine communities, primarily along portions of the Coyote Canal, Coyote 
Canal Extension, Coyote Alamitos Canal, and Almaden Calero Canal where high-quality 
serpentine communities were mapped by SCVWD botanist J. Hillman during surveys in 
2004 and 2008 (Figure 3.3-2], Projected activities along Upper Silver Creek, Coyote Creek, 
Coyote Canal Extension, Coyote Canal, Coyote Alamitos Canal, and Almaden Calero Canal 
(totaling 7.58 acres] would occur within designated critical habitat for the Bay checkerspot 
butterfly. Because the Bay checkerspot butterfly typically occurs high on hillsides in the 
Project Area rather than the lower locations of these canals, impacts to occupied Bay 
checkerspot butterfly habitat (and individuals] in work sites would be very limited, if in 
fact any such impacts were to occur at all. Figure 3.3-5 indicates the distribution of the Bay 
checkerspot butterfly and its designated critical habitat in the Project Area. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-94 


December 2011 
Project No. 10.005 



N:\Projects3000\3166-01\Reports\EIR June 2011 



Z 



LEGEND 

Santa Clara County Boundary 
SMP Project Area 

////, Bay Checkerspot Butterfly Critical Habitat 
Bay checkerspot butterfly CNDDB Records 
Approximate Location 
General Area 


Figure 3.3-5: Bay Checkerspot Butterfly Distribution in Santa Clara County 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 






































This page intentionally left blank. 



3.3 Biological Resources 


Furthermore, some projected activities would occur in or very close to serpentine habitats 
along portions of Upper Silver Creek and Coyote Creek (Figure 3.3-2], No high-quality 
serpentine communities were identified in work sites during SCVWD's surveys. As a result, 
the Bay checkerspot butterfly would be unlikely to occur in such areas, and a low 
probability exists that the other serpentine-associated invertebrate species (i.e., Horn's 
micro-blind harvestman, Jung's micro-blind harvestman, and Opler's longhorn moth] 
would be present in these areas. 

Proposed Project activities in serpentine habitat may include spot-removal of sediment 
plugs from the canals themselves, vegetation management along the tops and inboard 
sides of the levees/roads immediately adjacent to canals, vegetation management 
activities within the canal, and animal conflict management. As described under 
Determination of Impacts to Wildlife and Fisheries, these activities could result in the direct 
mortality or injury of special-status invertebrates associated with serpentine communities. 

Suitable habitat for the Bay checkerspot's larval and adult food plants (i.e., dwarf plantain, 
purple owl's-clover, and exserted paintbrush] occurs in upland areas along the edges of the 
canals, and in and along the canal-side levee roads. In particular, dwarf plantain can be 
locally abundant in disturbed areas such as levees. Thus, these species may be impacted by 
people or equipment moving along the sides of the canals during access to canal work 
sites, or by activities that focused on the maintenance of the canal-side roads and levees, 
such as mowing, herbicide application, and animal conflict management. 

Equipment use, vehicle traffic, and worker foot traffic along canals may result in the injury 
or mortality of serpentine dependent invertebrates including the Bay checkerspot 
butterfly (larvae and pupae] and its host plants (e.g., physically breaking, crushing, wilting, 
or uprooting plants and damaging their roots as a result of soil disturbance by heavy 
equipment]. Additionally, butterflies and their host plants may suffer injury or mortality as 
a result of vegetation clearing for access roads and staging areas. Impacts to Opler's 
longhorn moth would be similar, although because the two harvestman species typically 
occur in or under rocks, Proposed Project activities likely would have little effect on these 
species. 

As discussed for serpentine communities under Impact BIO-3, SMP Update activities are 
projected to impact up to 5.04 linear miles of canal within high-quality serpentine 
communities. Assuming (conservatively] that areas up to 20 feet on either side of the canal 
could be impacted, projected activities could impact up to 24.43 acres of high-quality 
serpentine communities. Although special-status, serpentine-associated invertebrates may 
occur in only a subset of this area, some potential would exist for impacts to populations of 
these species throughout that area. 

SCVWD would implement several measures to address the impact of Proposed Project 
activities on serpentine-dependent special-status animal species, including pre-project 
planning BMPs to minimize the area of disturbance. Implementation of the BMPs 
specifically designed to protect sensitive natural communities and to avoid impacts to the 
Bay checkerspot butterfly and its critical habitat would avoid or minimize impacts to these 
species by the identification and avoidance of serpentine habitat and serpentine- 
dependent special-status species. These BMPs are as follows, and a description of each is 
provided in Table 2-12. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-95 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Applicable Best Management Practices 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-9: Avoid Impacts to Special-Status Plant Species and Sensitive Natural 
Vegetation Communities 

BMP GEN-10: Avoid Impacts to Bay Checkerspot Butterfly and Associated Critical 
Habitat 

BMP GEN-21: Staging and Stockpiling of Materials 
Conclusion 

By implementing these BMPs, SCVWD is expected to be able to reduce impacts to 
serpentine-associated special-status species. Nevertheless, the Proposed Project may 
result in residual impacts to special-status serpentine-associated invertebrates and their 
habitats because complete avoidance could not be accomplished while still meeting the 
project goals for public health and safety directives. This impact would be significant 
because of the regional rarity of these species (Significance Criteria A and B], 
Implementation of Mitigation Measure BIO-6 would reduce this residual impact to a less- 
than-significant level. Implementation of Mitigation Measure BIO-3 for serpentine plant 
communities and Mitigation Measure BIO-4 for serpentine-associated special-status plant 
populations would help to reduce impacts to special-status serpentine-associated 
invertebrates by providing compensation for impacts to high-quality occurrences of the 
communities in which these special-status species typically occur. However, Mitigation 
Measure BIO-6 still would be necessary to assure mitigation specific to the special-status 
invertebrate species that were impacted was provided. Mitigation Measure BIO-6 would be 
implemented to reduce the impact to serpentine-associated special-status invertebrates to 
a less-than-significant level. 

Mitigation Measure BIO-6: Implement Compensatory Mitigation for Impacts to 
Serpentine-Associated Special-Status Invertebrates 

SCVWD will compensate for its impacts to populations and habitat of serpentine- 
associated special-status invertebrates through the preservation and management of 
serpentine communities as described for Mitigation Measure BIO-3. The procedures for 
identifying impacts to potential habitat of these species will occur as described for 
serpentine communities under Mitigation Measure BIO-3. Mitigation lands will be 
preserved and managed as described for Mitigation Measure BIO-3 as well, with the 
qualification that for any impacts to high-quality serpentine communities within Bay 
checkerspot butterfly critical habitat, the compensatory mitigation lands also must be in 
Bay checkerspot critical habitat. The management and monitoring of mitigation lands, as 
described in the HMMP, will include measures specifically targeting the Bay checkerspot 
butterfly, which will serve as a proxy for the other special-status invertebrates. 

The HMMP will be provided to the USFWS for review because one of the serpentine- 
associated special-status species (Bay checkerspot butterfly] for which this HMMP will be 
prepared is a federally listed species regulated by the USFWS. It is possible that this 
mitigation measure may be refined during the Section 7 consultation process with the 
USFWS (e.g., in the Biological Opinion covering Project effects on the Bay checkerspot 
butterfly], in which case the refinements required by the USFWS would be implemented. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-96 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


MM BIO-6 will mitigate impacts to serpentine-associated special-status invertebrates to 
less-than-significant levels by enhancing, managing, and protecting populations of these 
species so that the SMP does not substantially reduce the number or restrict the range of 
rare or endangered serpentine-associated invertebrates or have a substantial adverse 
effect on special-status serpentine-associated invertebrates. 

Impact BIO-7: Loss of Ordinance Trees 

(Significance Criterion F; Less than Significant with Mitigation) 

For the purposes of the SMP Update, unless an agreement between SCVWD and a 
municipality states otherwise, ordinance trees are defined based on the applicable local 
ordinance. Often, ordinance trees must meet a minimum size requirement. However, some 
ordinances are not size-based but species based (e.g., all oaks] and, in some cases, no 
distinction is made between native and non-native species. Ordinance-sized trees are 
common in many of the riparian habitats along the creeks that are maintained by SCVWD, 
and they are present in some non-instream areas as well. In addition to providing riparian 
functions and values, as described in the habitats section above, larger trees are 
particularly valuable because they provide the highest-quality nesting sites for raptors, 
they may contain cavities that serve as roost sites for bats or nesting/denning sites for 
other animals, they provide large amounts of coarse woody debris to the stream 
ecosystem, and they promote high foliage height diversity, which in turn increases the 
local diversity of birds. They also provide important shading and aesthetic values. As a 
result of their high value, such trees are protected by local ordinances of Santa Clara 
County and a number of municipalities within SCVWD's jurisdictional area. Thus, these 
trees merit special consideration in assessing impacts of the Proposed Project. 

Removal of all hazard trees and trees greater than 12 inches dbh is not included in the SMP 
Update. As a result, few ordinance trees are likely to be impacted by Proposed Project 
activities. Nevertheless, vegetation management and bank stabilization activities 
associated with the Proposed Project may result in the removal of ordinance trees, and 
some potential would exist for all Proposed Project activities indirectly to affect the health 
of ordinance trees through herbicide application or damage to roots resulting from the 
movement of heavy equipment. 

SCVWD would implement a pre-project planning BMP, limiting impacts to the minimum 
area required, to address the impact of Proposed Project activities on ordinance trees. This 
BMP is as follows; a description of this BMP is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-4: Minimize the Area of Disturbance 

Conclusion 

Implementation of BMP GEN-4 would minimize the loss of ordinance trees, but complete 
avoidance of these trees may not be practicable. In the absence of mitigation measures, this 
impact would be significant in accordance with Significance Criterion F. When direct 
removal of ordinance trees by SCVWD could not be avoided, Mitigation Measure BIO-7 
would be implemented to reduce residual impacts to a less-than-significant level. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-97 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Mitigation Measure BIO-7: Tree Replacement 

The SCVWD will replace ordinance trees as follows. As discussed under Mitigation Measure 
BIO-2, removal of trees sized 6-12 inches dbh will be mitigated through the individual 
planting of replacement trees. Section 5.5 in Appendix C ( Mitigation for Tree and Shrub 
Removals 6-12 inches dbh ] provides a specific tree appraisal and evaluation protocol to 
determine how replacement planting should occur. The protocol in Section 5.5 of Appendix 
C will involve carefully assessing targeted tree removals for their existing conditions and 
functions, including their canopy cover, local area value, ecosystem benefits, and 
ecosystem detriments. Using a cumulative ranking method, tree replacement mitigation 
ratios for removed trees (6-12 inches dbh] will occur at either 1:1, 2:1, or 3:1 (replacement 
tree to removed tree], depending on the overall quality and function of the removed tree. 
Therefore, if any trees 6-12 inches dbh that are removed are ordinance trees (depending 
on the locality in which tree removal occurs], then mitigation will be provided as described 
in Section 5.5 of Appendix C. 

It is possible that this mitigation measure may be refined during the permitting process by 
the USACE, CDFG, or RWQCB, in which case the refinements required by these agencies 
would be implemented. 

MM BIO-7 will mitigate impacts to ordinance trees to less-than-significant levels by 
replacing trees that are removed so that the SMP does not conflict with the provisions of 
local tree ordinances. 

Impact BIOS: Impacts on Steelhead 

(Significance Criteria A, B, and E; Less than Significant with Mitigation) 

The federally listed steelhead, including both the Central California Coast (CCC] steelhead 
and the South-Central California Coast (SCCC] steelhead, rely on adequate flows, water 
temperatures, water depths, and velocities; appropriate spawning and rearing substrates 
(e.g., riverbed gravels]; and availability of instream cover and food for survival and 
reproduction in the creeks of the Project Area. Proposed maintenance activities may 
significantly alter these conditions and result in the direct injury or mortality of these fish 
as generally described under Determination of Impacts to Wildlife and Fisheries. 

Effects of bank stabilization on steelhead would depend largely on their use of the affected 
reach, the existing (pre-stabilization] condition of the bank, and the stabilization methods 
that were employed. For example, along reaches used solely for fish passage between 
spawning/rearing locations and San Francisco Bay, bank stabilization activities would be 
unlikely to have a substantial impact regardless of the stabilization methods employed. 
Conversely, bank stabilization activities within spawning or rearing habitat, or upstream 
from such habitats, may have more substantial effects on steelhead and their habitats. 
Replacement of a natural or "soft" bank, especially one supporting riparian vegetation, 
with "hard" substrate such as concrete or riprap that was not conducive to riparian 
revegetation would be likely to result in an adverse effect on steelhead habitat. In contrast, 
replacement of a hardened bank with softer stabilization methods, especially those that 
enhanced instream complexity, would result in a considerable net benefit to steelhead by 
increasing habitat complexity and enhancing refugia, pool-riffle complexes, and rearing 
habitat. SCVWD would prioritize the use of soft stabilization methods that provided these 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-98 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


benefits. Bank stabilization also could lead to degradation of habitat through the loss of 
undercut banks. 

The extent of potential impacts to steelhead and their habitat resulting from bank 
stabilization activities is difficult to quantify, because stabilization activities cannot be 
projected and because the magnitude of the impact of stabilization would depend on the 
type of repair method used and the location of the repair project. However, the extent of 
bank stabilization work that is expected to occur in steelhead habitat would be relatively 
low, based on SMP activities conducted since 2002 . Between 2002 and 2010, 
fapproximat e ly less than 1 mile of bank stabilization work per year has occurred 
throughout the Project Area, including non-steelhead streams)-. SCVWD's records indicate 
that less than 20 percent of this bank stabilization work occurred in unmodified channels, 
which likely provide the highest-qualitv habitat for steelhead. Furthermore. SCVWD 
expects that no more than half of the bank repairs during the period 2012-2022 to consist 
of impervious hardscape bank stabilization work. As a result, and because of the potential 
long-term benefits of bank stabilization to steelhead habitat described above, little long¬ 
term adverse impact to steelhead habitat is expected to occur as a result of 2012-2022 
bank stabilization activities. 

Before work within an active channel that contains water, the reach would be dewatered. 
By implementing BMP GEN-15, fish would be relocated from streams supporting steelhead 
to minimize mortality and implementing BMP GEN-1 would limit in-channel activities to 
the period when steelhead would be least likely to be present. As a result, no adult 
steelhead are expected to be present in work sites when dewatering and fish relocation 
occur; and thus, no adults would be impacted by the maintenance activity or relocation. 
However, fry and juveniles may be present, especially if maintenance activities occurred 
near spawning or rearing habitat. During capture and relocation, fry and juveniles may be 
subjected to stress, injury, or mortality associated with netting, electrofishing, temporary 
captivity, and release into the relocation site. SCVWD fish relocation activities for the SMP 
from 2002-2009 resulted in a steelhead mortality rate of 0.9 percent (SCVWD 2002-2004, 
2006-2009). Although the relocation sites would be carefully selected by SCVWD fisheries 
biologists based on criteria specified in the Fish Relocation Guidelines, some potential 
would exist for changes in temperature or water chemistry between the capture and 
release site, or densities of predators or competitors at the release site, to result in 
increased stress, injury, or mortality as well. Although the benefits of steelhead relocation 
would far outweigh the complete loss of individuals that would occur if fish were not 
relocated before dewatering took place, relocation could still result in adverse effects. 

The main impact to steelhead resulting from sediment removal would be the removal of 
spawning gravel. Because projected 2012-2022 sediment removal activities would include 
some higher-elevation reaches where steelhead would be likely to spawn, such as in the 
Guadalupe River watershed, adverse effect of sediment removal on steelhead may occur 
because of the removal of gravel. Gravel removal would reduce the extent and availability 
of potential spawning habitat, and possibly rearing habitat, in the short term by removing 
existing spawning habitat and in the long term by reducing gravel supply within a creek. 

Bank stabilization and sediment removal activities often necessitate the operation of heavy 
equipment within the stream bed fafter dewateringl. Movement of heavy equipment may 
compact the substrate, potentially killing benthic invertebrates fwhich may serve as prey 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-99 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


for steelhead). embedding gravel within finer sediments, and otherwise altering habitat for 
fish and their prey. 

The locations where projected sediment removal would overlap steelhead habitat can be 
predicted and are shown in Figure 3.3-6. Sediment removal is projected to occur along 
approximately 12.61 miles of steelhead bearing streams from 2012-2022, with 
11.34 miles in the Santa Clara Basin (thus affecting CCC steelhead] and 1.27 miles in the 
Pajaro Basin (thus affecting SCCC steelhead]. Table 3.3-4011 summarizes the length of 
each steelhead-accessible creek in which sediment removal has been projected from 
2012-2022. Although Figure 3.3-6 depicts the stream reaches in which sediment removal 
is projected, not every linear mile indicated as "projected" would actually undergo 
sediment removal. As explained in Chapter 2, Project Description, a "work area percentage" 
has been applied to some reaches in which only a certain percentage of the reach would 
undergo sediment removal. Table 3.3-4011 takes the "work area percentage" into account. 
As a result, the linear miles of sediment removal in Table 3.3-4011 represent only a certain 
percentage (the "work area percentage"] of the projected work areas shown in Figure 3.3- 
6 . 


Table 3.3-4011. Projected Sediment Removal Work on Streams Supporting Steelhead, 
2012-2022 


Creek/River 

Work Areas from 
2002-2012, also 
projected for 
2012-2022 
(miles) 

New Work Areas 
for 2012-2022 
(miles) 

Total Work 
Areas for 2012- 
2022 
(miles) 


Central California Coast Steelhead 


San Francisquito Creek 

0.00 

0.01 

0.01 

Stevens Creek 

0.80 

0.04 

0.84 

Guadalupe River/Creek 

1.15 

5.83 

6.98 

Alamitos Creek 

0.01 

0.31 

0.32 

Coyote Creek 

0.00 

2.64 

2.64 

Upper Penitencia Creek 

0.01 

0.42 

0.43 

Los Gatos Creek 

0.00 

0.08 

0.08 

Calero Creek 

0.00 

0.04 

0.04 

Subtotal 

1.97 

9.37 

11.34 


South-Central California Coast Steelhead 


Uvas/Carnadero Creek 

0.00 

0.04 

0.04 

Llagas Creek 

0.38 

0.84 

1.22 

Bodfish Creek 

0.00 

0.01 

0.01 

Subtotal 

0.38 

0.89 

1.27 

Total 

2.35 

10.26 

12.61 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-100 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


Riparian vegetation serves a number of important roles for steelhead that would be altered 
by projected vegetation management activities, as discussed previously. However, 
Casagrande (2010], studying steelhead in Uvas Creek, found that steelhead grew much 
more quickly, and thus were much larger by their first winter, at less shaded, somewhat 
warmer sites, which had higher prey abundance compared to densely shaded, cooler sites. 
Casagrande verified that invertebrate biomass was considerably higher at less heavily 
shaded sites than under a dense forest canopy. His findings confirm those of other studies 
that demonstrate greater stream productivity (Murphy et al. 1981, Bilby and Bisson 1992, 
Quinn et al. 1997, Ambrose et al. 2004] and greater salmonid production (Wilzbach et al. 
1986, 2005, Nislow and Lowe 2006] along reaches with lower canopy closure and higher 
light levels. Fish sampling by SCVWD in reaches below dense canopy has found very low 
densities of fish (of any species], apparently as a result of very low food densities 
(M. Moore, unpublished data]. Therefore, thinning of vegetation as a result of the Proposed 
Project's vegetation management component may have benefits to steelhead, by increasing 
prey abundance in areas that are currently heavily shaded. In addition, larger steelhead 
tend to have higher winter survival, and thus the availability of conditions that would 
contribute to rapid growth, especially in the first year, could benefit steelhead populations 
considerably. 

Vegetation management activities also would include the application of herbicides, as 
discussed above. Herbicides have the potential to result in impacts on steelhead as a direct 
effect on the survival, reproduction, and growth of individual steelhead, as well as indirect 
effects, such as reduction of the prey base or modification of their habitat. However, such 
effects would be minimized by SCVWD, using herbicide formulations approved for aquatic 
environments and adhering to state and federal regulations concerning herbicide use, as 
well as implementing SCVWD's BMPs. 

USEPA has conducted ecological risk assessments to determine the potential risks of 
labeled uses of several herbicides, including three proposed for use by SCVWD (glyphosate, 
pendimethalin, and triclopyr] on Pacific salmonids. Evaluated herbicides proposed for use 
by SCVWD are as follows, with a summary of USEPA's effects determination: 

■ Glyphosate: for all uses with application rates of 5 pounds of active 
ingredient/acre or less, use results in no effect on the Central California 
Coast or South-Central California Coast steelhead. For application rates 
above 5 pounds active ingredient/acre, the pesticide may affect but is not 
likely to adversely affect these ESUs. 

* Pendimethalin: no effect on the Central California Coast or South-Central 
California Coast steelhead. 

■ Triclopyr: may affect but is not likely to adversely affect the Central 
California Coast or South-Central California Coast steelhead. 

SCVWD would use a surfactant to enhance the performance of herbicides. Surfactants aid 
the ability of a herbicide to penetrate the surface of vegetation, by increasing its ability to 
spread over vegetation, stick to foliage, and penetrate thick cuticles. Most aquatic 
herbicides either require or highly recommend the use of a surfactant to achieve 
reasonable levels of control. In instances where surfactants are absent from the tank mix, 
the level of control often is reduced. A reduction in control causes a greater return 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-101 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


frequency, which translates to more herbicide being used in the system and more frequent 
disturbance to the site. 

In general, aquatic species (e.g., fish and amphibians] are more susceptible to adverse 
effects than terrestrial wildlife because of the potential for surfactants to alter cell 
permeability, thus increasing the potential for absorption of chemicals through their thin, 
moist skin. Some surfactants, particularly those that are nonylphenol-based, have been 
documented to result in chemical-induced lethargy and unconsciousness in fish, which can 
result in an increased risk of predation as well as cause estrogenic effects (Smith et al. 
2004, USFS 2007], However, SCVWD proposes to limit surfactant use to the products that 
are documented to have the least toxic effect on aquatic life, Agri-dex and Competitor. Both 
of these surfactants are oil-based (Competitor is vegetable oil-based while the primary 
ingredient in Agri-dex is a paraffin-based oil] and function by increasing the absorption of 
herbicides through plant tissues. They are especially useful in increasing the penetration of 
herbicides through the bark of woody brush or tree stems (Bakke 2007], A study on the 
toxicity of surfactants to juvenile rainbow trout concluded that Agri-dex was less toxic to 
rainbow trout than two other commonly used surfactants, R-ll and LI 700 (Smith et al. 
2004], and the 2006 Supplemental Environmental Assessment of NOAA Fisheries 
Implementation Plan for the Community Based Restoration Program (NOAA 2006] 
concluded that was among the surfactants least toxic to marine and aquatic organisms (it 
is unknown whether Competitor was assessed]. 

The use of these pesticides and surfactants according to existing label directions and the 
California Department of Pesticide Regulation PRESCRIBE database, which provides 
information consistent with USEPA's Interim Measures Bulletins for Protection of 
Endangered Species for user-selected sites and pesticides, would minimize direct adverse 
effects on steelhead. However, herbicide use still could result in type conversion of 
riparian and wetland vegetation types, reduction in cover associated with vegetation, and 
modification of prey base for steelhead. 

Vegetation management also is projected in the SMP Update. Therefore, the locations 
where projected vegetation management would overlap steelhead habitat can be 
predicted; these locations are shown in Figure 3.3-7 for instream herbicide application, 
Figure 3.3-8 for non-instream herbicide application, and Figure 3.3-9 for other vegetation 
management methods, such as hand removal, pruning, and mowing. Tables 3.3-4412. 3.3- 
42- 13. and 3.3-4344 summarize the length of each steelhead-accessible creek in which 
instream herbicide application, non-instream herbicide application, and manual vegetation 
management, respectively, are projected from 2012-2022. 

Although Figures 3.3-7, 3.3-8, and 3.3-9 depict the stream reaches in which vegetation 
management activities are projected, not every linear mile indicated as "projected" in these 
figures would actually be subject to vegetation management. As explained previously, a 
"work area percentage" has been applied to some reaches in which only a certain 
percentage of the reach would undergo certain management activities. Tables 3.3-44 12. 
3.3-4313. and 3.3-4314 take the "work area percentage" into account, and thus the linear 
miles of sediment removal in these tables represent a subset of the projected work areas 
shown in the corresponding figures. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-102 


December 2011 
Project No. 10.005 



N:\Projects3000\3166-01\Reports\EIR June 2011 


LEGEND 

Santa Clara County Boundary 
SMP Project Area 

New Sediment Removal, 2012-2022 
Sediment Removal, both 2002-2012 and 2012-2022 
CCC Steelhead Critical Habitat 

Additional CCC Steelhead Accessible Creeks (Not Critical Habitat) 

SCCC Steelhead Critical Habitat 

Note: Project area maps provide a general description of work type and area for 
the 2012-2022 SMP and are not intended to represent the exact locations of 
future work. 



Merced County 



H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-6: Projected Sediment Removal, 2012-2022, along Steelhead Streams 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 































This page intentionally left blank. 



N:\Projects3000\3166-01\Reports\EIR June 2011 


LEGEND 

Santa Clara County Boundary 
SMP Project Area 

New Instream Herbicide Application, 2012-2022 
Instream Herbicide Application, both 2002-2012 and 2012-2022 
CCC Steelhead Critical Habitat 

Additional CCC Steelhead Accessible Creeks (Not Critical Habitat) 

SCCC Steelhead Critical Habitat 

Note: Project area maps provide a general description of work type and area for 
the 2012-2022 SMP and are not intended to represent the exact locations of 
future work. 



Merced County 



H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-7: Projected Instream Herbicide Application, 2012-2022, along Steelhead Streams 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 

































This page intentionally left blank. 



N:\Projects3000\3166-01\Reports\EIR June 2011 


LEGEND 

Santa Clara County Boundary 
SMP Project Area 

New Non-Instream Herbicide Application, 2012-2022 
Non-Instream Herbicide Application, both 2002-2012 and 2012-2022 
CCC Steelhead Critical Habitat 

Additional CCC Steelhead Accessible Creeks (Not Critical Habitat) 

SCCC Steelhead Critical Habitat 

Note: Project area maps provide a general description of work type and area for 
the 2012-2022 SMP and are not intended to represent the exact locations of 
future work. 



Merced County 



H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-8: Projected Non-Instream Herbicide Application, 2012-2022, along Steelhead Streams 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 



































This page intentionally left blank. 



N:\Projects3000\3166-01\Reports\EIR June 2011 


,>n Cr e ^ 



Alameda County 



V o \ 



liA 



i rr-A 


f 



/ 





C* 

\ . rv e ' 
\iencia ° 


ek 


* . 


San Mateo County 



Pacific Ocean 


0 12,000 24,000 

N Feet 


A 



Santa > 


County 


4 Miles 



Monterey County 



LEGEND 

| | Santa Clara County Boundary 

SMP Project Area 

New Manual Vegetation Management, 2012-2022 

Manual Vegetation Management, both 2002-2012 and 2012-2022 

CCC Steelhead Critical Habitat 

Additional CCC Steelhead Accessible Creeks (Not Critical Habitat) 
SCCC Steelhead Critical Habitat 

Note: Project area maps provide a general description of work type and area for 
the 2012-2022 SMP and are not intended to represent the exact locations of 
future work. 


San Joaquin 
County 



m. 


San Benito County 


V 


Merced County 




H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-9: Projected Manual Vegetation Management, 2012-2022, along Steelhead Streams 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 






























This page intentionally left blank. 



3.3 Biological Resources 


The Project Area contains designated critical habitat for both the CCC and SCCC steelhead 
(Figure 3.3-6], Stream maintenance activities would result in both adverse and beneficial 
effects on designated critical habitat, as described above for steelhead habitat in general. 
Specifically, Proposed Project activities would impact the primary constituent elements 
[PCEs] of critical habitat involving freshwater spawning, rearing, and migration habitat for 
both populations, as well as estuarine habitats of the Central California Coast steelhead. 

SCVWD would implement a variety of BMPs to avoid and minimize impacts to steelhead 
and their habitats. These BMPs are listed below and described in Table 2-12. 

Table 3.3-4412. Projected Instream Herbicide Application Work on Streams Supporting 
Steelhead, 2012-2022 



Work Areas from 

New Work Areas 

Total Work 

Creek/River 

2002-2012 Period 

for 2012-2022 

Areas for 

Also Projected for 

(miles) 

2012-2022 


2012-2022 (miles) 


(miles) 


Central California Coast Steelhead 


Stevens Creek 

0.08 

<0.01 

0.08 

Guadalupe River 

0.34 

0.00 

0.34 

Los Gatos Creek 

0.29 

0.00 

0.29 

Guadalupe Creek 

0.12 

0.04 

0.16 

Alamitos Creek 

0.24 

0.00 

0.24 

Coyote Creek 

0.17 

0.19 

0.36 

Upper Penitencia Creek 

0.24 

0.18 

0.42 

Calero Creek 

0.00 

0.04 

0.04 

Subtotal 

1.48 

0.45 

1.93 


South-Central California Coast Steelhead 


Pajaro River 

0.00 

0.42 

0.42 

Uvas/Carnadero Creek 

0.00 

0.33 

0.33 

Llagas Creek 

0.00 

1.80 

1.80 

Subtotal 

0.00 

2.55 

2.55 

Total 

1.48 

3.00 

4.48 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-103 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


Table 3.3-4213. Projected Non-Instream Herbicide Application Work on Streams 
Supporting Steelhead, 2012-2022 



Work Areas from 

New Work Areas 

Total Work 

Creek/River 

2002-2012 Period 

for 2012-2022 

Areas for 

Also Projected for 

(miles) 

2012-2022 


2012-2022 (miles) 


(miles) 


Central California Coast Steelhead 


San Francisquito Creek 

1.31 

0.13 

1.43 

Stevens Creek 

1.44 

0.06 

1.50 

Guadalupe River 

8.96 

1.99 

10.95 

Los Gatos Creek 

0.01 

0.23 

0.24 

Guadalupe Creek 

2.36 

0.00 

2.36 

Alamitos Creek 

3.35 

0.00 

3.35 

Coyote Creek 

5.42 

1.94 

7.36 

Upper Penitencia Creek 

1.49 

0.02 

1.51 

Calero Creek 

0.64 

0.01 

0.65 

Subtotal 

24.98 

4.38 

29.35 


South-Central California Coast Steelhead 


Pajaro River 

0.00 

0.17 

0.17 

Uvas/Carnadero Creek 

0.32 

1.77 

2.09 

Llagas Creek 

7.14 

1.15 

8.29 

Subtotal 

7.46 

3.09 

10.55 

Total 

32.44 

7.47 

39.90 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-104 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


Table 3.3-4314. Projected Manual Vegetation Management Work on Streams 
Supporting Steelhead, 2012-2022 



Work Areas from 

New Work Areas 

Total Work 

Creek/River 

2002-2012 Period 

for 2012-2022 

Areas for 

Also Projected for 

(miles) 

2012-2022 


2012-2022 (miles) 


(miles) 


Central California Coast Steelhead 


San Francisquito Creek 

0.19 

0.04 

0.23 

Stevens Creek 

1.15 

0.02 

1.17 

Guadalupe River 

5.30 

5.01 

10.31 

Los Gatos Creek 

0.00 

1.43 

1.43 

Guadalupe Creek 

1.90 

0.89 

2.79 

Alamitos Creek 

1.52 

1.72 

3.24 

Coyote Creek 

4.99 

3.27 

8.26 

Upper Penitencia Creek 

0.56 

0.23 

0.79 

Calero Creek 

0.05 

0.07 

0.12 

Subtotal 

15.66 

12.68 

28.34 


South-Central California Coast Steelhead 


Pajaro River 

0.00 

0.42 

0.42 

Uvas/Carnadero Creek 

2.12 

0.27 

2.39 

Llagas Creek 

7.43 

0.00 

7.43 

Bodfish Creek 

0.00 

0.01 

0.01 

Subtotal 

9.55 

0.70 

10.25 

Total 

25.21 

13.38 

38.59 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-105 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


Applicable Best Management Practices 

BMP GEN-1: In-Channel Work Window 

BMP GEN-2: Instream Herbicide Application Work Window 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-8: Protection of Sensitive Fauna Species from Herbicide Use 

BMP GEN-15: Salvage Native Aquatic Vertebrates from Dewatered Channels 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-33: Dewatering for Non-Tidal Sites 

BMP GEN-34: Dewatering in Tidal Work Areas 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP SED-3: Restore Channel Features 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 
BMP VEG-3: Use Appropriate Equipment for Instream Removal 
BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 
BMP BANK-2: Concrete Use near Waterways 

Conclusion 

By implementing these BMPs, SCVWD is expected to be able to reduce impacts to 
steelhead. Nevertheless, the Proposed Project would result in residual impacts to this 
species and its habitats because complete avoidance could not be accomplished while still 
meeting the project goals for public health and safety directives. This impact would be 
significant because of the regional rarity of this species and the importance of Santa Clara 
County creeks to the species (Significance Criteria A, B, and E], Implementation of 
Mitigation Measure BIO-8 would reduce this residual impact to a less-than-significant 
level. 

As discussed under Impacts BIO-1 and BIO-2, Mitigation Measure BIO-1 and Mitigation 
Measure BIO-2 would require SCVWD to provide compensatory mitigation for impacts to 
wetland, aquatic, and riparian habitats. This mitigation may take a variety of forms, and 
not all of this mitigation would occur along steelhead streams. However, Mitigation 
Measure BIO-1 and Mitigation Measure BIO-2 would result in benefits to steelhead through 
wetland, aquatic, and riparian habitat restoration, enhancement, and protection, which 
would help to maintain water quality, cover, and instream habitat complexity for 
steelhead. In addition, Mitigation Measure BIO-8 and Mitigation Measure BIO-9 would be 
implemented to compensate more specifically for Proposed Project impacts to steelhead. 
Mitigation Measure BIO-8 and Mitigation Measure BIO-9 would be implemented to reduce 
the impacts on steelhead to a less-than-significant level. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-106 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Mitigation Measure BIOS: Augmentation of Spawning Gravel 

SCVWD will implement gravel augmentation as mitigation for SMP impacts to CCC and 
SCCC steelhead spawning habitat. If more than Sthf 100 square feet of sediment removal is 
proposed along steelhead streams, an SCVWD fisheries ecologist will assess the sediment 
removal site for spawning and rearing habitat quality before the initiation of work. The 
biologist will determine the extent of sediment that is proposed for removal and that is 
considered to be “high-quality" spawning gravel, based on the following criteria: 

■ Less than 25-30 percent fines less than 6.35 mm (Kondolf 2000, Kondolf and 
Wolman 1993] 

■ Less than 12-14 percent fines less than 0.85 mm (Kondolf 2000] 

■ D50 (median particle size] of 12.5 to 22.0 mm, based on D50 of rainbow 
trout and steelhead from 30 to 65 cm length (Kondolf and Wolman 1993], 
corresponding to a range of 275 to 640 cm of steelhead adults recovered in 
streams of the San Francisco estuary (Leidy et al. 2005] 

■ Minimum patch size greater than 1.1 m 2 (Trush 1991] 

The habitat needs to be accessible under typical flows for when the appropriate life stages 
are present. Suitable depths and velocities must be available during flows typical of 
spawning season. Factors related to accessibility include depth and velocity criteria, which 
for spawning, are: 

■ Depth: 10-150 cm (Moyle 2002] 

■ Velocity: 20-155 cm/s (Moyle 2002] 

If more than StKf 100 square feet of high-quality gravel will be removed along steelhead 
streams, compensatory mitigation will be provided by the installation of suitable spawning 
gravel along the affected creek at a 1:1 (mitigatiomimpact] ratio on a square footage or 
acreage basis. Locations where sediment removal is performed at fish ladders will not 
require gravel augmentation. The mitigation site will be as close to the impacted reach as is 
feasible, and will be located within a steelhead-accessible reach of the same creek. The site 
will be selected with input from the fisheries ecologist, taking channel capacity and other 
SMP-related factors into account. The fisheries ecologist will prepare specifications for the 
mitigation, including size, type, depth, and configuration of gravel. The mitigation will be 
implemented within 1 year following the impact. 

Mitigation Measure BIOS: Augmentation of Instream Complexity for Non-Tidal 
Stream Fish 

SCVWD will provide mitigation for loss of instream complexity, which provides habitat 
heterogeneity, cover, and refugia during high flows, by in-kind installation of structures 
that provide such complexity. Before sediment removal, bank stabilization, or large woody 
debris removal activities, the affected area will be surveyed by an SCVWD fisheries 
ecologist to identify any features that provide high-quality instream complexity for fish. 
The ecologist will determine that such features are of "high quality" based on a 
combination the presence of one or more of the following criteria: 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-107 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


* Large woody debris providing cover and refugia from high flow velocities 

■ Deep pools providing rearing habitat and refugia from high flow velocities 

» Cobble/boulder features providing cover, refugia from high flow velocities, 
and velocities suitable for good invertebrate drift 

If such high-quality features must be removed during Proposed Project activities, 
compensatory mitigation will be provided by the installation of instream complexity 
features on a 0.51:1 f impact: mitigation :impact ] basis, on the basis of either the number of 
complexity features or the area that is affected hydraulically by the features that are 
removed; the fisheries ecologist will determine which of these two metrics is appropriate 
based on the values to fish provided by the impacted features. Thus, one instream 
complexity feature will be installed for every two one that are is removed, or an instream 
complexity feature hydraulically affecting roughly half the same area of the feature [s] 
removed will be installed. This ratio is l e ss than 1:1 und e r th e und e rstanding that e rosion, 
d e position, tr ee- falls, and d e bris mobilization within a f e w y e ars following th e r e moval of 
instr e am compl e xity will naturally r e introduc e som e compl e xity to th e str e am. 

As examples, enhancing instream complexity may involve: 

■ enlarging an existing large woody debris feature; 

■ anchoring a large woody debris feature; 

■ geomorphically shaping an instream bar or bed feature for improved 
habitat; 

■ enhancing a pool feature threatened by sedimentation; or 

■ enhancing streambed conditions to increase the range of flow velocity and 
habitat conditions. 

Priority for these mitigation activities will be given to SMP sites where instream features 
cannot be retained during construction because of conflicting objectives. For example, if a 
channel pool configuration cannot be retained during a bank protection job and the area is 
devoid of other complex pool features, then this area will be evaluated for the addition of 
an instream complexity feature. 

In addition to enhancing existing features, new instream features may be developed to 
achieve several habitat objectives, including: increasing pool habitat in homogenized 
stream reaches, providing escape cover for rearing and spawning fish, deepening feeding 
areas in riffle habitat, creating a variety of stream flow velocities for cover, sorting gravel, 
and providing resting areas for upstream migration. Additionally, improving instream 
function can benefit other aquatic flora and fauna by improving the overall stream 
complexity for which these species depend on for survival. If effective, such new instream 
complexity features (particularly in highly modified, urban streams] can augment or 
replace existing structural features required for successful reproduction and rearing of 
native fish and amphibians in the freshwater environment. 

Newly developed instream habitat improvements may use log structures, boulder 
structures, or a combination of both log and boulder structures to achieve more complex 
habitats. Possible configurations of boulders or logs include weirs, clusters, single and 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-108 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


opposing wing deflectors, spider logs, and digger logs. The construction materials selected 
for each instream complexity feature will depend on the target objective and site 
conditions. 

The selected mitigation site will be as close to the impacted reach as is technically feasible. 
For instream complexity features that are removed by sediment removal or bank 
stabilization activities, mitigation will be incorporated into the same reach where 
complexity was removed to the extent feasible. The site will be selected with input from 
the fisheries ecologist, taking channel capacity and other SMP-related factors into account. 
The fisheries ecologist will prepare specifications for the mitigation, including size, type, 
and configuration of the feature. The mitigation will be implemented within 1 year 
following the impact. The fisheries ecologist will then inspect the completed complexity 
feature to assure that it meets the criteria for "high quality" instream complexity listed 
above. 

It is possible that MM BIO-8 and MM BIO-9 may be refined during the Section 7 
consultation process with the NMFS (e.g., in the Biological Opinion covering Project effects 
on steelhead] or by the USACE, CDFG, or RWQCB in permits issued by these agencies, in 
which case the refinements required by these agencies would be implemented. 

MM BIO-8 and BIO-9 together will mitigate impacts to steelhead to less-than-significant 
levels by enhancing habitat for this species so as to protect its populations, thereby 
ensuring that the SMP does not substantially reduce the number or restrict the range of 
this threatened species, have a substantial adverse effect on this special-status species, or 
impede the use of its nursery sites. 

Mitigation activities such as gravel augmentation (Mitigation Measure BIO-8] and 
installation of instream complexity (Mitigation Measure BIO-9] could result in impacts to 
aquatic species during installation; however, the net effect of these measures on fish and 
amphibians would be beneficial. 

Impact BIO-9: Impacts on the Pacific Lamprey and Monterey Roach 
(Significance Criteria A, B, and E; Less than Significant with Mitigation) 

The Pacific lamprey is not on any special-status species list. However, this anadromous 
species likely has been impacted by many of the factors that threaten the steelhead, and it 
occurs in a number of SCVWD-maintained creeks. Thus, the potential effects of Proposed 
Project activities on this fish have been assessed. It is currently known to occur in the 
Project Area in the Guadalupe River and San Francisquito, Coyote, Upper Penitencia, Lower 
Silver, Guadalupe, Alamitos, Stevens, and Uvas Creeks. The Monterey roach (a California 
species of special concern] is a small minnow that occurs in the Project Area in streams 
within the Pajaro River watershed. Specifically, it is known to occur in Llagas and Uvas 
Creeks, and it likely is present in other Project Area creeks within the Pajaro River Basin. 

As described under Determination of Impacts to Wildlife and Fisheries, proposed 
maintenance activities may result in adverse effects to habitat used by both of these fish 
through dewatering, fish relocation, increased turbidity, changes in habitat structure, 
effects of heavy equipment use on these species, their prey, and their habitat, and other 
impact pathways. Permanent habitat impacts to these species' habitats are expected to be 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-109 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


very limited but could potentially occur if bank stabilization activities replaced their 
habitat with hardscape. Electrofishing for fish relocation, stranding, herbicide and 
surfactant use, and increased turbidity may result in the direct injury or mortality of 
individual fish. 

The distribution of these fish in the Project Area is not as well known as that of steelhead, 
and thus no detailed impact estimates are provided. However, Table 3.3-4011 for 
steelhead provides an estimate of the potential extent of sediment removal and vegetation 
management activities along creeks that could support the Pacific lamprey, and Tables 3.3- 
4412 through 3.3-43-14 provide an estimate of the potential extent of projected instream 
herbicide, non-instream herbicide, and manual vegetation management activities, 
respectively, along creeks that could support the lamprey. Similarly, the projected 
activities along creeks within the Pajaro Basin, as listed in those tables, provide an 
estimate of the potential impacts of Proposed Project activities along creeks that could 
support the Monterey Roach. 

When performing any type of maintenance activity that would necessitate work within or 
adjacent to the active channel, SCVWD would implement BMPs to reduce impacts to water 
quality (e.g., erosion and sediment control, spill prevention, standard herbicide 
requirements]. In addition, implementation of BMPs related to dewatering of work sites 
would assure that, before dewatering, the best means to bypass flow through a work site 
would be determined, to minimize disturbance to the channel and avoid direct mortality of 
fish. Sediment removal BMPs would assure that low-flow channels within non-tidal 
streams were returned as closely as possible to their original location and configured with 
the appropriate depth for fish passage. These BMPs are as follows, and a description of 
each is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-1: In-Channel Work Window 

BMP GEN-2: Instream Herbicide Application Work Window 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-8: Protection of Sensitive Fauna Species from Herbicide Use 

BMP GEN-15: Salvage Native Aquatic Vertebrates from Dewatered Channels 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-33: Dewatering for Non-Tidal Sites 

BMP GEN-34: Dewatering in Tidal Work Areas 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP SED-3: Restore Channel Features 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 
BMP VEG-3: Use Appropriate Equipment for Instream Removal 
BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 
BMP BANK-2: Concrete Use near Waterways 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-110 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Conclusion 

Implementation of BMPs would reduce impacts on the Pacific lamprey and Monterey roach 
and their habitats. However, because of the factors potentially threatening these species' 
populations and the relatively limited ranges of both species, impacts to individuals and 
their habitats resulting from the Proposed Project would be significant (Significance 
Criteria A, B, and E]. 

As discussed under Impacts BIO-1 and BIO-2, Mitigation Measure BIO-1 and Mitigation 
Measure BIO-2 would require SCVWD to provide compensatory mitigation for impacts to 
wetland, aquatic, and riparian habitats. This mitigation may take a variety of forms, and 
not all of this mitigation would occur along streams that supported the Pacific lamprey and 
Monterey roach. However, Mitigation Measure BIO-1 and Mitigation Measure BIO-2 would 
result in benefits to these species through wetland, aquatic, and riparian habitat 
restoration, enhancement, and protection, which would help to maintain water quality, 
cover, and instream habitat complexity for these species. In addition, implementation of 
Mitigation Measure BIO-9 would increase instream complexity, and thus could be expected 
to benefit the Pacific lamprey and Monterey roach in a manner similar to that described for 
steelhead. Mitigation Measure BIO-1, Mitigation Measure BIO-2, and Mitigation Measure 
BIO-9 would be implemented to reduce the impact to the Pacific lamprey and Monterey 
roach to a less-than-significant level by compensating for Proposed Project impacts to 
habitat and individuals. 

Impact BIO-10: Impacts on the Longfin Smelt and Green Sturgeon 
(Significance Criteria A and B; Less than Significant with Mitigation) 

Longfin smelt (state listed as threatened] is known to occur, and green sturgeon (federally 
listed as threatened and a California species of special concern] could potentially occur, in 
the tidal reaches of South Bay sloughs. If these species were to occur in reaches near 
proposed maintenance activities, the health of individuals could be impaired by decreased 
water quality (e.g., increased turbidity resulting from sediment removal in lower reaches 
of creeks or spills of fuels or chemicals] . Habitat of these species would be affected little by 
Proposed Project activities, but removal of vegetation along sloughs could potentially 
result in minor adverse effects on these species. 

The only sediment removal activities projected within tidal waters where southern green 
sturgeon could potentially occur would take place along uppermost Alviso Slough, from the 
Union Pacific Railroad tracks just below Gold Street upstream to the upper limits of tidal 
waters near Tasman Drive (a distance of approximately 1.4 miles]. Within this 1.4-mile 
reach, sediment would be removed from approximately 40 percent of the reach at a time, 
and sediment removal would occur approximately five times during the 10-year Proposed 
Project period. Vegetation management is projected along approximately 6.89 miles of 
sloughs, including 3.59 miles where vegetation management also was projected for 2002- 
2012, and 3.30 miles where new work is projected. 

These species occur infrequently and in low numbers, if at all, in the immediate Project 
Area, and they are not expected to spawn in the Project Area. Furthermore, they would be 
unlikely to occur upstream from tidal reaches because of a lack of suitable spawning 
conditions. Because of the infrequency of these species' occurrence in the Project Area, the 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-111 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


very limited extent of Proposed Project activities in tidal habitats, and the fact that 
instream activities that could result in adverse water quality effects would not extend far 
downstream in tidal sloughs (i.e., to areas where these species were more likely to occur], 
a low probability would exist that proposed maintenance activities would result in 
substantial effects on the health or survival of any individuals or have a substantial adverse 
effect on these species' habitats. Nevertheless, the Proposed Project would affect tidal 
habitat, which is designated critical habitat for the green sturgeon, as described generally 
for sturgeon habitat above. Specifically, Proposed Project activities could affect the PCEs of 
critical habitat involving food resources, water quality, and sediment quality for the green 
sturgeon. 

SCVWD would implement BMPs for all activities along sloughs in which the longfin smelt 
and green sturgeon could potentially occur. These BMPs are as follows, and a description 
of each is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-1: In-Channel Work Window 

BMP GEN-2: Instream Herbicide Application Work Window 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-8: Protection of Sensitive Fauna Species from Herbicide Use 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-34: Dewatering in Tidal Work Areas 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP SED-3: Restore Channel Features 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 
BMP VEG-3: Use Appropriate Equipment for Instream Removal 
BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 
BMP BANK-2: Concrete Use near Waterways 

Conclusion 

Implementation of BMPs would reduce impacts on the longfin smelt and green sturgeon 
and their habitats. Because of the expected infrequency of these species' occurrence in the 
Project Area and likely low abundance when they occurred, the BMPs likely would be 
adequate to reduce impacts to these species to very low levels. However, because the 
longfin smelt has been recorded in tidal sloughs in the Proposed Project vicinity, and 
because relatively little is known about how these species use South Bay sloughs, some 
potential would exist for Proposed Project activities to result in significant impacts 
(Significance Criteria A and B], 

As discussed under Impact BIO-1, Mitigation Measure BIO-1 includes mitigation for 
impacts to tidal wetlands and other waters, which would be the habitats in which the 
longfin smelt and green sturgeon could potentially occur. SCVWD would use the 21 acres of 
e xc e ss tidal marsh restoration that it has accomplished at the Island Ponds as available 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-112 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


mitigation for impacts to tidal wetlands and aquatic habitats, as well as tidal species such 
as the longfin smelt and green sturgeon. This mitigation would include tidal channels that 
could be used by green sturgeon and that already have been demonstrated to be used by 
longfin smelt (Hobbs 2011], Therefore, Mitigation Measure BIO-1 would be implemented 
to reduce the impacts on the longfin smelt and green sturgeon to a less-than-significant 
level, assuring that the SMP Update would not substantially reduce the number or restrict 
the range of these threatened species, have a substantial adverse effect on these special- 
status species, or in the case of the longfin smelt, impede the use of its nursery sites. It is 
possible that this mitigation may be refined by the NMFS, which regulates impacts to the 
southern green sturgeon, during Section 7 consultation (e.g., in a Biological Opinion] 
and/or CDFG, which regulates impacts to the longfin smelt, during Section 2081 
consultation (e.g., in an Incidental Take Permit], in which case these refined measures 
would be implemented. 

Impact BIO-11: Impacts on the California Tiger Salamander 
(Significance Criteria A, B, and E; Less than Significant with Mitigation) 

The California tiger salamander ffederallv and state- listed as threatened and stat e list e d as 
e ndang e r e d ] has been largely extirpated from the valley floor, and extant populations in 
the Project Area are now limited primarily to areas with seasonal pools and stock ponds 
around the periphery of the Project Area, particularly in the less heavily developed areas 
and areas that have not been heavily cultivated. Because of its distribution in the Project 
Area, potential impacts to California tiger salamanders would be relatively limited. 
However, they may pass through work sites during seasonal movements to and from 
breeding ponds and may use upland burrows within work sites as refugia (e.g., to prevent 
dehydration during the dry summer and autumn months]. In addition, some potential 
would exist for California tiger salamanders to breed in portions of canals, particularly 
inoperable canals such as the Coyote and Coyote Extension Canals. 

As described under Determination of Impacts to Wildlife and Fisheries, proposed 
maintenance activities may affect California tiger salamander foraging or dispersal habitat 
and/or individuals (e.g., during maintenance activities or from increased mortality after 
construction]. For example, maintenance activities may result in the injury or mortality of 
individuals as a result of worker foot traffic, equipment use, or vehicle traffic. Daily and 
seasonal movements throughout individuals' home ranges may be temporarily affected 
during maintenance activities because of disturbance, and substrate vibrations may cause 
individuals to move out of refugia, exposing them to a greater risk of predation or 
desiccation. In addition, tiger salamanders may be crushed in their burrows by the passage 
of heavy equipment or trapped and suffocated, and petrochemicals, hydraulic fluids, and 
solvents that are spilled or leaked from construction vehicles or equipment may kill 
individuals. 

Removal of burrows in levees, a component of the management of animal conflicts, could 
impact California tiger salamanders because of the potential for tiger salamanders to use 
burrows as refugia. Direct mortality of individuals may occur because of filling or 
compaction of crevices/holes on levee surfaces or slopes. In addition, the loss of 
subterranean habitat caused by filling of burrows and the use of surface barriers to 
burrowing animals would reduce the availability of refugia, potentially subjecting 
dispersing salamanders to increased predation or desiccation if they were unable to find 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-113 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


suitable refugia. Loss of subterranean habitat also may result in the displacement of 
invertebrates that serve as a food source for this species. Control of burrowing mammal 
populations would reduce the availability of upland refugia for the salamander. The extent 
of effects to California tiger salamander habitat resulting from management of animal 
conflict activities is difficult to quantify because the extent of and specific locations for 
animal conflicts management are not generally known. More than 9 miles of levees along 
canals occur in areas where the California tiger salamander is considered extant and where 
animal conflict management may occur. In addition, animal conflict management could 
occur in other non-projected locations within potential California tiger salamander habitat. 

By implementing BMPs GEN-12 and GEN-15, tiger salamanders would be relocated from 
work sites before the onset of maintenance activities that potentially could threaten 
individuals. Individuals that were found during pre-activity surveys and relocated to 
suitable habitat outside of the work site may be subjected to physiological stress and face a 
greater risk of predation, or may undergo increased competition with salamanders already 
present in the area to which they were relocated. 

The vast majority of proposed sediment removal activities would be in areas where 
California tiger salamanders do not currently occur. Figure 3.3-10 depicts all projected 
activities relative to the expected distribution of this species in the Project Area, based on 
known occurrences (primarily from CNDDB 2011] and habitat suitability. As shown in this 
figure,, this species is largely absent from the portions of the Santa Clara Valley floor that 
have been heavily impacted by urban development and agricultural activities. Because 
most projected activities would occur in these valley-floor areas, impacts to areas that 
could potentially support this species would be very limited. 

Because sediment removal is a projected activity for the SMP, the potential locations where 
sediment removal could impact tiger salamanders can be predicted. These locations are 
depicted in Figure 3.3-11 and summarized in Table 3.3-4415. For clarity, Figure 3.3-11 
only shows the projected sediment removal activities within areas where the California 
tiger salamander is expected to be extant. Because no sediment removal activities in 
predicted California tiger salamander habitat occurred (or will occur] from 2002-2012, all 
impacts to California tiger salamanders from 2012-2022 would be new activities. 

Sediment removal is projected in habitat where the California tiger salamander is expected 
to be extant, primarily along the urban fringe, along approximately 1.03 miles of creek. The 
sediment removal projections listed in Table 3.3-4415 provide only a rough estimate of 
potential impacts that would result from sediment removal, for several reasons. First, 
Table 3.3-4415 depicts the linear miles of channels that would be subject to impacts rather 
than the acreage of sediment removal itself, under the assumption that impacts to tiger 
salamanders would be most likely to occur because of movement of heavy equipment 
along channels rather than excavation of sediments within the channel. In addition, 
although the species has been recorded in or adjacent to some of the creeks in these areas 
(e.g., Saratoga Creek, Guadalupe Creek, Coyote Creek, Dexter Canyon Creek], no occurrence 
records are located within the immediate impact areas. Tiger salamanders are not 
expected to breed in these stream habitats (with the possible exception of some segments 
of canals; Coyote Alamitos and Almaden Calero Canals are the only canals where sediment 
removal is projected within the current distribution of the species]. Rather, they are 
expected to occur here only during seasonal movements to and from breeding ponds, or 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-114 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


possibly while using upland refugia along these streams. Finally, any tiger salamanders 
present within areas affected by sediment removal activities would be likely to be 
underground during the dry season and during daylight hours, when such activities would 
occur, thus reducing the potential for impact. With implementation of the BMPs listed later 
in this section, particularly BMP GEN-12 (Protection of Special-Status Amphibian and 
Reptile Species], short-term effects on California tiger salamanders as a result of sediment 
removal activities are expected to be minimal. 

Because vegetation management is a projected activity for the SMP Update, the potential 
locations where vegetation management could impact tiger salamanders also can be 
predicted. These locations are depicted in Figure 3.3-12 and summarized in Table 3.3- 
45-16 (as the linear miles of channel within potential California tiger salamander habitat 
where vegetation management activities are projected]. Although the California tiger 
salamander has been recorded in or adjacent to some of the creeks listed above, no 
occurrence records are located within the immediate impact areas, and tiger salamanders 
are not expected to breed in these stream habitats. Rather, they are expected to occur here 
only during seasonal movements to and from breeding ponds, or possibly while using 
upland refugia along these streams. Additionally, any tiger salamanders present within 
areas affected by vegetation management activities are likely to be underground during 
the dry season, when many such activities would occur, and during daylight hours, when 
all vegetation management would take place, thus reducing the potential for impact. 

Vegetation management activities would include the application of aquatic herbicide 
(instream] and herbicide application to terrestrial areas (outside the water], as discussed 
above. Because California tiger salamanders are not expected to breed in the channels in 
the work sites and spend little time above ground in upland habitat, herbicide application 
likely would have limited effects on the survival, reproduction, or growth of California tiger 
salamanders that may be present in areas where herbicides were applied. Rather, the 
potential for effects on tiger salamanders resulting from vegetation management would 
pertain primarily to the physical presence of people and equipment during vegetation 
management activities. Nevertheless, some potential would exist for salamanders to be 
exposed to herbicides and surfactants during migration or feeding on the ground’s surface, 
and herbicides also would reduce vegetative cover for salamanders while these animals 
were moving aboveground. 

Critical habitat has been designated for the California tiger salamander (Figure 3.3-9). Projected 
activities would have the potential to affect designated critical habitat for the species in ways 
described above and under Determination of Impacts to Wildlife and Fisheries. Specifically, 
Proposed Project activities could affect the PCEs of critical habitat involving upland habitats 
with subterranean refugia and upland dispersal habitat for the tiger salamander, as described 
generally for habitat impacts above. However, adverse effects of Proposed Project activities on 
tiger salamander critical habitat would be limited to approximately 4.55 acres of work sites near 
the Almaden Calero Canal. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-115 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Table 3.3-4415. Projected Sediment Removal Impacts in Areas of Potential California 


Tiger Salamander Occurrence, 2012-2022 


Creek/River 

Sediment Removal Impacts, 
2012-2022 
(miles) 

Alamitos Creek 

0.04 

Almaden-Calero Canal 

0.63 

Bodfish Creek 

0.01 

Calero Creek 

0.04 

Coyote Alamitos Canal 

0.01 

Coyote Creek 

0.14 

Guadalupe Creek 

0.08 

Llagas Creek 

0.04 

Los Gatos Creek 

0.02 

San Francisquito Creek 

0.01 

Stevens Creek 

0.01 

Uvas-Carnadero Creek 

0.00 

Total 

1.03 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


Table 3.3-4516. Projected Vegetation Management Impacts in Areas of Potential 
California Tiger Salamander Occurrence, 2012-2022 


Creek/River 

Vegetation 
Management 
Impacts, 
2012-2022 only 
(ac) 

Vegetation 
Management 
Impacts, 
2002-2010 and 
2012-2022 
(ac) 

Total Vegetation 
Management 
Impacts, 
2012-2022 
(ac) 

Instream Herbicide Application 

Adobe Creek 


0.03 

0.03 

Alamitos Creek 

0.04 


0.04 

Almaden-Calero Canal 


0.32 

0.32 

Calero Creek 

0.05 


0.05 

Coyote Alamitos Canal 


0.06 

0.06 

Coyote Canal 


0.48 

0.48 

Coyote Canal Extension 


0.52 

0.52 

Coyote Creek 

0.48 


0.48 

Edmundson Creek 

0.00 


0.00 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-116 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


Table 3.3-4516. Projected Vegetation Management Impacts in Areas of Potential 
California Tiger Salamander Occurrence, 2012-2022 


Creek/River 

Vegetation 
Management 
Impacts, 
2012-2022 only 
(ac) 

Vegetation 
Management 
Impacts, 
2002-2010 and 
2012-2022 
(ac) 

Total Vegetation 
Management 
Impacts, 
2012-2022 
(ac) 

Guadalupe Creek 

0.09 


0.09 

Llagas Creek 

0.01 


0.01 

Los Gatos Creek 

0.03 


0.03 

Pajaro River 

0.48 


0.48 

Uvas-Carnadero Creek 

0.09 


0.09 

Total 

1.27 

1.41 

2.68 


Non-Instream Herbicide Application 


Adobe Creek 


0.00 

0.00 

Almaden-Calero Canal 


4.95 

4.95 

Coyote Alamitos Canal 


0.66 

0.66 

Coyote Canal 


1.05 

1.05 

Coyote Creek 

0.09 


0.09 

Edmundson Creek 

0.00 

0.03 

0.03 

Lions Creek 


0.28 

0.28 

Llagas Creek 

0.02 


0.02 

Norwood Creek 

0.05 


0.05 

Pajaro River 

1.04 


1.04 

San Francisquito Creek 

0.12 


0.12 

Santa Teresa Creek 

0.03 

0.00 

0.03 

Stevens Creek 

0.04 


0.04 

Uvas-Carnadero Creek 

0.17 


0.17 

Total 

1.56 

6.97 

8.53 


Manual Vegetation Management 


Alamitos Creek 

0.19 


0.19 

Almaden-Calero Canal 

6.92 


6.92 

Bodfish Creek 

0.16 


0.16 

Calero Creek 

1.98 


1.98 

Coyote Alamitos Canal 


1.28 

1.28 

Coyote Creek 

2.55 


2.55 

Edmundson Creek 

0.02 

0.00 

0.03 

Guadalupe Creek 

0.71 


0.71 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-117 


December 2011 
Project No. 10.005 





3.3 Biological Resources 


Table 3.3-4516. Projected Vegetation Management Impacts in Areas of Potential 
California Tiger Salamander Occurrence, 2012-2022 


Creek/River 

Vegetation 
Management 
Impacts, 
2012-2022 only 
(ac) 

Vegetation 
Management 
Impacts, 
2002-2010 and 
2012-2022 
(ac) 

Total Vegetation 
Management 
Impacts, 
2012-2022 
(ac) 

Lions Creek 

0.28 

0.00 

0.29 

Llagas Creek 

0.20 

0.00 

0.21 

Los Gatos Creek 

0.05 


0.05 

Norwood Creek 

0.04 


0.04 

Pajaro River 

1.52 


1.52 

San Francisquito Creek 

0.01 


0.01 

Santa Teresa Creek 

1.09 

0.07 

1.16 

South East Santa Teresa Creek 

2.53 


2.53 

Stevens Creek 

0.00 


0.00 

Uvas-Carnadero Creek 

1.94 

0.50 

2.44 

West Little Llagas Creek 

0.58 


0.58 

TOTAL 

20.77 

1.85 

22.65 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


SCVWD would implement the following BMPs to reduce impacts to individual California 
tiger salamanders and their habitats (a description of each is provided in Table 2-12], 

Applicable Best Management Practices 

BMP GEN-2: Instream Herbicide Application Work Window 
BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-8: Protection of Sensitive Fauna Species from Herbicide Use 

BMP GEN-12: Protection of Special-Status Amphibian and Reptile Species 

BMP GEN-15: Salvage Native Aquatic Vertebrates from Dewatered Channels 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-33: Dewatering for Non-Tidal Sites 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 

BMP VEG-3: Use Appropriate Equipment for Instream Removal 

BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 

BMP BANK-2: Concrete Use near Waterways 

BMP ANI-1: Avoid Redistribution of Rodenticides 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-118 


December 2011 
Project No. 10.005 



N:\Projects3000\3166-01\Reports\EIR June 2011 


LEGEND 

Santa Clara County Boundary 
| [ SMP Project Area 

Vegetation Management: 2012-2022 Projections 
Sediment Removal: 2012-2022 Projections 


'//// California Tiger Salamander Critical Habitat 
California Tiger Salamander Distribution 
Not Historic Habitat 
Presumed Extinct 
Presumed Extant 

California Tiger Salamander CNDDB Records 
• Specific Location 
O Approximate Location 
General Area 



Note: Project area maps provide a general description of 
work type and area for the 2012-2022 SMP and are not 
intended to represent the exact locations of future work. 


Merced County 



H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-10: Known Occurrences and Expected Distribution of the California Tiger Salamander 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 


















































■queiq qjaj Xueuopusiui sSed siqj. 




3 


H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-11: Projected Sediment Removal in Areas of Potential California Tiger Salamander Occurrence, 2012-2022 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 















































■queiq qjaj Xueuopusiui sSed siqj. 



N:\Projects3000\3166-01\Reports\EIR June 2011 



© 


H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-12: Projected Vegetation Management in Areas of Potential California Tiger Salamander Occurrence, 2012-2022 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 





















































■queiq qjaj Xueuopusiui sSed siqj. 



3.3 Biological Resources 


BMP ANI-4: Animal Control in Sensitive Amphibian Habitat 
Conclusion 

Although BMPs would reduce the magnitude and extent of Proposed Project impacts on 
the California tiger salamander, residual impacts would remain because repeated impacts 
to habitat as well as loss of habitat via burrow removal could not be avoided. Because of 
the regional rarity of this species, impacts to California tiger salamander and its habitat 
would be significant (Significance Criteria A, B, and E). Implementation of Mitigation 
Measure BIO-10 would reduce the impact to California tiger salamander and its habitat to a 
less-than-significant level. 

As discussed under Impacts BIO-1 and BIO-2, Mitigation Measure BIO-1 and Mitigation 
Measure BIO-2 would require SCVWD to provide compensatory mitigation for impacts to 
wetland, aquatic, and riparian habitats. This mitigation may take a variety of forms, and 
not all of this mitigation would occur in areas where California tiger salamander occurred. 
However, Mitigation Measure BIO-1 and Mitigation Measure BIO-2 could result in benefits 
to California tiger salamander through wetland restoration and the protection and 
management of mitigation lands that may support this species. Nevertheless, Mitigation 
Measure BIO-10 would be implemented to reduce the impact to California tiger 
salamander and its habitat to a less-than-significant level. 

Mitigation Measure BIO-10: Implement Compensatory Mitigation for the 
California Tiger Salamander 

SCVWD will provide mitigation to compensate for unavoidable impacts to California tiger 
salamanders and their habitat. SCVWD would refine the quantification of impacts to 
California tiger salamander habitat on an annual basis. At the end of each year's 
maintenance period, SCVWD will determine the extent of impacts to lands that are both 
within the potential range of the California tiger salamander and within potentially 
suitable habitat for the species. To determine whether the SMP impacts are within the 
potential range of the species, SCVWD will rely on the mapping in Figure 3.3-10 (which 
may be as modified over the course of 2012-2022, based on any new information that may 
modify the understanding of the species' potential range in the Project Area], To determine 
habitat suitability, an SCVWD biologist will determine whether the impact areas support 
land uses that are not conducive to California tiger salamander use, such as developed 
lands; all other land uses will be considered potential California tiger salamander habitat. 

Compensation for these effects will be provided via the protection, enhancement, and 
management of habitat that currently supports, or can support, this species at a 2:1 
f mitigation: impact :mitigation l ratio, on an acreage basis. Compensatory mitigation may be 
carried out through one or both of the following methods, in order of preference: 

■ The preservation, management, and enhancement (e.g., through long-term 
management targeted toward this species] of high-quality habitat that is 
already occupied by California tiger salamanders 

■ The restoration or enhancement of degraded habitat or habitat that is 
unsuitable for use by California tiger salamanders, but that (a] is in close 
proximity to areas of known occurrence and (b] can be made more suitable 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-119 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


for use via construction of one or more breeding ponds or management to 
improve the quality and availability of burrows in upland habitat 

Because most, if not all, impacts to California tiger salamander habitat will consist of 
modification of upland refugial/dispersal habitat (rather than aquatic breeding habitat!. 
mitigation lands will also consist of upland habitat for this species. All mitigation lands for 
this species must be located within Santa Clara County and within the area where the 
species is thought to be extant as shown in Figure 3.3-10 (or as otherwise modified over 
the course of 2012-2022, based on any new information that may modify the 
understanding of the species' potential range in the Project Area], SCVWD will develop an 
HMMP describing the measures that will be taken to manage the property and to monitor 
the effects of management on the California tiger salamander. That plan will include, at a 
minimum, the following: 

■ a summary of impacts to California tiger salamander habitat and 
populations, and the proposed mitigation; 

■ a description of the location and boundaries of the mitigation site and 
description of existing site conditions; 

■ a description of measures to be undertaken if necessary to enhance (e.g., 
through focused management] the mitigation site for California tiger 
salamanders; 

■ proposed management activities, such as managed grazing, management of 
invasive plants, measures targeted at sustaining populations of burrowing 
mammals, or other measures to maintain high-quality habitat for California 
tiger salamanders; 

■ a description of species monitoring measures on the mitigation site, 
including specific, objective goals and objectives fincluding maintaining or 
improving habitat suitability for California tiger salamanders], performance 
indicators and success criteria fincluding maintaining or increasing the 
abundance of upland refugia for California tiger salamanders! monitoring 
methods (such as sampling of the abundance of upland refugia], data 
analysis, reporting requirements, and monitoring schedule. Determining 
other specific performance/success criteria requires information regarding 
the specific mitigation site, its conditions, and the specific enhancement and 
management measures tailored to the mitigation site and its conditions. For 
example, performance criteria for a mitigation site providing only upland 
habitat for California tiger salamanders would include the maintenance of 
grassland habitat of a suitable height and density for burrowing mammals, 
and maintenance of suitable burrowing mammal populations, whereas a 
mitigation site providing salamander breeding habitat would also include 
criteria related to adequate depth and hydroperiod of breeding habitat. As a 
result, thos e additional specific criteria will be defined in the HMMP rather 
than in this SEIR. Nevertheless, the performance/success criteria described 
in the HMMP will guide the mitigation to manage and protect high-quality 
habitat for the California tiger salamander, adequate to compensate for 
impacts. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-120 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


■ a description of the management plan's adaptive component, including 
potential contingency measures for mitigation elements that do not meet 
performance criteria; and 

■ a description of the funding mechanism for the long-term maintenance and 
monitoring of the mitigation lands. 

If lands that SCVWD currently owns, such as mitigation lands acquired for the California 
red-legged frog for the 2002-2012 SMP, can be enhanced (e.g., via the construction of 
breeding ponds] in such a way as to substantially improve their value to California tiger 
salamanders, then SCVWD may use those lands as mitigation for the California tiger 
salamander. After mitigation has been provided for impacts to a specific area supporting 
the California tiger salamander from a specific year's SMP Update activities, future (i.e., 
repetitive] impacts to that area will not require additional mitigation. 

The HMMP will be provided to the USFWS and CDFG for review because this species is 
both state and federally listed. It is possible that this mitigation measure may be refined 
during the Section 7 consultation process with the USFWS (e.g., in the Biological Opinion 
covering Project effects on the California tiger salamander] or the Section 2081 
consultation process with the CDFG (e.g., in an Incidental Take Permit], in which case the 
refinements required by these agencies would be implemented. 

MM BIO-10 will mitigate impacts to the California tiger salamander to less-than-significant 
levels by enhancing, managing, and protecting habitat for this species so as to protect its 
populations, thereby ensuring that the SMP does not substantially reduce the number or 
restrict the range of this threatened/endangered species, have a substantial adverse effect 
on this special-status species, or impede the use of its nursery sites. 

Impact BIO-12: Impacts on the California Red-Legged Frog 
(Significance Criteria A, B, and E; Less than Significant with Mitigation) 

The California red-legged frog is federally listed as threatened and a California species of 
special concern. As described under Determination of Impacts to Wildlife and Fisheries, 
proposed maintenance activities may affect California red-legged frog habitat (breeding, 
foraging, or dispersal] and/or individuals (e.g., during maintenance activities or from 
increased mortality after construction]. For example, maintenance activities may result in 
the injury or mortality of individuals as a result of worker foot traffic, equipment use, or 
vehicle traffic. Daily and seasonal movements throughout individuals' home ranges may be 
temporarily affected during maintenance activities because of disturbance, and substrate 
vibrations may cause individuals to move out of refugia, exposing them to a greater risk of 
predation or desiccation. In addition, red-legged frogs may be crushed in their burrows by 
the passage of heavy equipment or trapped and suffocated. Furthermore, petrochemicals, 
hydraulic fluids, and solvents that were spilled or leaked from construction vehicles or 
equipment, or spot-baiting associated with management of animal conflicts, may kill 
individuals of this species. 

Removal of burrows in levees, a component of the management of animal conflicts, could 
impact California red-legged frogs because of the potential for these frogs to use burrows 
as refugia. Direct mortality of individuals may occur because of filling or compaction of 
crevices/holes on levee surfaces or slopes. In addition, the loss of subterranean habitat 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-121 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


caused by filling of burrows and the use of surface barriers to burrowing animals would 
reduce the availability of refugia, potentially subjecting dispersing frogs to increased 
predation or desiccation if they were unable to find suitable refugia. Control of burrowing 
mammal populations would reduce the availability of upland refugia for the frog. The 
extent of effects to California red-legged frog habitat resulting from management of animal 
conflicts is difficult to quantify because the extent of and specific locations for animal 
conflict management generally are not known. More than 12 miles of levees along Calera 
Creek and the Almaden Calero, Coyote Extension, and Coyote Canals occur in areas where 
the California red-legged frog is considered extant and where animal conflict management 
may occur. In addition, animal conflict management could occur in other non-projected 
locations within potential California red-legged frog habitat. 

When performing any type of maintenance that would necessitate work within or adjacent 
to the active channel, SCVWD would implement BMPs (listed below] to reduce impacts to 
water quality (e.g., erosion and sediment control, spill prevention, standard herbicide 
requirements]. Implementation of BMPs related to dewatering of work sites would assure 
that, before dewatering, the best means to bypass flow through a work site would be 
determined, to minimize disturbance to the channel and avoid direct mortality of aquatic 
animals such as amphibians. In addition, by implementing BMPs GEN-12 and GEN-15, red- 
legged frogs would be relocated from work sites before the onset of maintenance activities 
that potentially could threaten individuals of this species. However, individuals that were 
found during pre-activity surveys and relocated to suitable habitat outside of the work site 
may be subjected to physiological stress and greater risk of predation, or may undergo 
increased competition with frogs already present in the area to which they were relocated. 

Similar to the California tiger salamander, the vast majority of proposed sediment removal 
activities would be in areas where red-legged frogs do not currently occur. Figure 3.3-13 
depicts all projected activities relative to the expected distribution of this species in the 
Project Area, based on known occurrences (primarily from CNDDB 2011] and habitat 
suitability. As shown in this figure, red-legged frogs are largely absent from the portions of 
the Santa Clara Valley floor that have been heavily impacted by urban development and 
agricultural activities. 

Since 2004, SCVWD has conducted annual surveys for the presence or absence of 
amphibians in numerous locations before the application of instream herbicides (see Table 
3.3-3]; no red-legged frogs were found at any of the locations listed in Table 3.3-3, 
suggesting that the distribution of this species in and near the Project Area is limited. This 
species is not known to breed in any of the areas where activities are proposed. Although 
breeding is possible, this species would be likely to occur sparingly as a non-breeding 
visitor, if at all, in most of the areas where Proposed Project activities would occur. 
Therefore, impacts to this species would be limited. 

Because sediment removal is a projected activity for the SMP Update, the potential 
locations where sediment removal could impact red-legged frogs can be predicted. These 
locations are depicted in Figure 3.3-14 and summarized in Table 3.3-4A17. For clarity, 
Figure 3.3-14 only shows the projected sediment removal activities within areas where the 
California red-legged frog is expected to be extant. No areas exist where sediment removal 
is projected in potential California red-legged frog habitat and where such sediment 
removal has occurred (or will occur] from 2002-2012. Therefore, all impacts to this 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-122 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


species from 2012-2022 would be new activities. Table 3.3-4617 takes the "work area 
percentage" into account, and thus the linear miles of sediment removal in this table 
represent a subset of the projected work areas shown in Figure 3.3-14. Unlike the 
California tiger salamander, impacts on California red-legged frogs may occur resulting 
from in-channel sediment removal activities. 

Thus, although the exact acreage of sediment removal activities in predicted California red- 
legged frog habitat cannot be determined because the location of staging areas and channel 
access points are not yet known, the potential impact is estimated to be approximately 1-2 
acres. Although the California red-legged frog has been recorded in or adjacent to some of 
the creeks in the Project Area (e.g., Saratoga Creek, Calabazas Creek, Guadalupe Creek, 
Coyote Creek, Dexter Canyon Creek], no occurrence records are located within the impact 
areas. Thus, with implementation of the BMPs discussed above, particularly BMP GEN-12 
(Protection of Special-Status Amphibian and Reptile Species], the impact on this species 
would be very limited. 

Table 3.3-4617. Projected Sediment Removal Impacts in Areas of Potential California 
Red-legged Frog Occurrence, 2012-2022 


Creek/River 

Sediment Removal Impacts, 
2012-2022 
(miles) 

Alamitos Creek 

0.04 

Almaden-Calero Canal 

0.63 

Bodfish Creek 

0.01 

Calabazas Creek 

0.03 

Calero Creek 

0.04 

Coyote Creek 

0.14 

Guadalupe Creek 

0.08 

Llagas Creek 

0.04 

Saratoga Creek 

0.01 

Stevens Creek 

0.01 

Uvas-Carnadero Creek 

0.00 

Total 

1.03 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 

Because vegetation management is a projected activity for the SMP Update, the potential 
locations where vegetation management could impact red-legged frogs can be predicted. 
These locations are depicted in Figures 3.3-15, 3.3-16, and 3.3-17 and summarized in Table 
3.3-4748. The table summarizes the acreage along each creek with potential red-legged 
frog habitat in which instream herbicide application, non-instream herbicide application, 
and manual vegetation management, respectively, have been projected from 2012-2022. 
Unlike the California tiger salamander, these three categories of vegetation management 
activities are described and shown separately for the red-legged frog because frogs, which 
potentially could breed in SCVWD creeks and are expected to use creeks and riparian 
habitats preferentially on the landscape, could potentially be impacted differently by these 
different types of activities. For example, instream herbicide application has greater 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-123 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


potential to result in adverse effects on red-legged frog eggs and larvae than non-instream 
herbicide application. Taking into account the overlap in areas where the different types of 
vegetation management would occur, vegetation management activities are projected to 
occur in a total of 35.42 acres of potential red-legged frog habitat. 


Table 3.3-4218. Projected Vegetation Management Impacts in Areas of Potential 
California Red-legged Frog Occurrence, 2012-2022 


Creek/River 

Vegetation 
Management 
Impacts, 
2012-2022 only 
(ac) 

Vegetation 
Management 
Impacts, 
2002-2010 and 
2012-2022 
(ac) 

Total Vegetation 
Management 
Impacts, 
2012-2022 
(ac) 

Instream Herbicide Application 

Adobe Creek 


0.04 

0.04 

Alamitos Creek 

0.04 


0.04 

Almaden-Calero Canal 


0.32 

0.32 

Calero Creek 

0.05 


0.05 

Cochran Channel 


0.00 

0.00 

Coyote Canal 


1.56 

1.56 

Coyote Canal Extension 


0.52 

0.52 

Coyote Creek 

0.48 


0.48 

Deer Creek 

0.01 


0.01 

Edmundson Creek 

0.03 


0.03 

Greystone Creek 


0.01 

0.01 

Guadalupe Creek 

0.09 


0.09 

Llagas Creek 

0.09 


0.09 

Pajaro River 

0.78 


0.78 

Prospect Creek 

0.00 


0.00 

Randol Creek 

0.00 

0.03 

0.03 

Uvas-Carnadero Creek 

0.30 


0.30 

West Branch Randol Creek 

0.01 


0.01 

Total 

1.88 

2.48 

4.36 

Non-Instream Herbicide Application 

Adobe Creek 


0.00 

0.00 

Almaden-Calero Canal 


4.95 

4.95 

Calera Creek 


0.19 

0.19 

Cochran Channel 

0.24 


0.24 

Coyote Canal 


3.28 

3.28 

Coyote Creek 

0.39 


0.39 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-124 


December 2011 
Project No. 10.005 





3.3 Biological Resources 


Table 3.3-4218. Projected Vegetation Management Impacts in Areas of Potential 
California Red-legged Frog Occurrence, 2012-2022 


Creek/River 

Vegetation 
Management 
Impacts, 
2012-2022 only 
(ac) 

Vegetation 
Management 
Impacts, 
2002-2010 and 
2012-2022 
(ac) 

Total Vegetation 
Management 
Impacts, 
2012-2022 
(ac) 

Deer Creek 

0.02 


0.02 

Edmundson Creek 

0.02 

0.62 

0.64 

Evergreen Creek 

0.02 


0.02 

Golf Creek 

0.19 


0.19 

Greystone Creek 

0.20 

0.33 

0.53 

Llagas Creek 

0.19 


0.19 

Pajaro River 

1.49 


1.49 

Prospect Creek 

0.00 


0.00 

RandolCreek 

0.00 

2.60 

2.60 

Saratoga Creek 

0.54 


0.54 

Stevens Creek 

0.04 


0.04 

Thompson Creek 

0.05 


0.05 

Uvas-Carnadero Creek 

0.14 


0.14 

West Branch Randol Creek 

0.62 


0.62 

West Little Llagas Creek 

0.49 

2.36 

2.84 

Total 

4.64 

14.33 

18.97 


Manual Vegetation 


Alamitos Creek 

0.19 


0.19 

Almaden-Calero Canal 

6.92 


6.92 

Bodfish Creek 

0.16 


0.16 

Calabazas Creek 

0.01 


0.01 

Calera Creek 

0.29 


0.29 

Calero Creek 

0.09 


0.09 

Coyote Creek 

2.62 


2.62 

Cribari Creek 

0.00 


0.00 

Deer Creek 

0.02 


0.02 

Edmundson Creek 

0.19 

0.72 

0.91 

Evergreen Creek 

0.03 


0.03 

Golf Creek 

0.12 


0.12 

Greystone Creek 

0.21 


0.21 

Guadalupe Creek 

0.51 


0.51 

Lions Creek 

0.00 


0.00 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-125 


December 2011 
Project No. 10.005 




3.3 Biological Resources 


Table 3.3-4218. Projected Vegetation Management Impacts in Areas of Potential 
California Red-legged Frog Occurrence, 2012-2022 


Creek/River 

Vegetation 
Management 
Impacts, 
2012-2022 only 
(ac) 

Vegetation 
Management 
Impacts, 
2002-2010 and 
2012-2022 
(ac) 

Total Vegetation 
Management 
Impacts, 
2012-2022 
(ac] 

Llagas Creek 

0.38 

0.09 

0.47 

McAbee Creek 

0.14 


0.14 

Pajaro River 

2.26 


2.26 

RandolCreek 

1.44 


1.44 

Saratoga Creek 

0.09 


0.09 

Stevens Creek 

0.00 


0.00 

Thompson Creek 

5.31 


5.31 

Uvas-Carnadero Creek 

1.82 


1.82 

West Branch Randol Creek 

0.27 


0.27 

Total 

23.07 

0.81 

23.88 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


Although Figures 3.3-15 to 3.3-17 depict the stream reaches in which vegetation 
management activities are projected, not every area indicated as "projected" on these 
figures would actually be subject to vegetation management. As explained previously, a 
"work area percentage" has been applied to some reaches in which only a certain 
percentage of the reach would undergo management activities. Table 3.3-47-18 takes the 
"work area percentage" into account, and thus the acreages of vegetation management in 
this table represent a subset of the projected work areas shown on the corresponding 
figures. 

Much of the projected vegetation management work would occur on levee tops and upper 
banks, not in the channel habitat where the frogs are expected to concentrate their 
activities. Thus, the potential for direct effects on red-legged frogs during vegetation 
management activities on the levees is substantially less than the potential during similar 
work in aquatic habitats. 

Mitigation activities such as gravel augmentation (Mitigation Measure BIO-8] and 
installation of instream complexity (Mitigation Measure BIO-9] could result in impacts to 
aquatic species during installation; however, the net effect of these measures on fish and 
amphibians would be beneficial. 

Vegetation management activities would include the application of herbicides, as discussed 
above. Herbicides have the potential to result in adverse effects on California red-legged 
frogs as a direct effect on the survival, reproduction, and growth of the frog itself, as well as 
indirect effects, such as reduction of the prey base or modification of its habitat. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-126 


December 2011 
Project No. 10.005 



San Mateo County 


LEGEND 

Santa Clara County Boundary 
SMP Project Area 

Vegetation Management: 2012-2022 Projections 
Sediment Removal: 2012-2022 Projections 
California Red-legged Frog Critical Habitat 
California Red-legged Frog Distribution 
Presumed Extinct 

Presumed Extant 
California Red-legged Frog CNDDB Records 
Specific Location 
£) Approximate Location 


Note: Project area maps provide a general description of 
work type and area for the 2012-2022 SMP and are not 
intended to represent the exact locations of future work. 



Merced County 


7 > 


H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-13: Known and Expected California Red-legged Frog Distribution in Santa Clara County 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 









































This page intentionally left blank. 



N:\Projects3000\3166-01\Reports\EIR June 2011 




H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-14: Projected Sediment Removal in Areas of Potential California Red-legged Frog Occurrence, 2012-2022 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 














































This page intentionally left blank. 



N:\Projects3000\3166-01\Reports\EIR June 2011 



LEGEND 

Santa Clara County Boundary 
SMP Project Area 

New Instream Herbicide Application within 
Potential CRLF Range, 2012-2022 
Instream Herbicide Application within Potential 
CRLF Range, both 2002-2012 and 2012-2022 

California Red-legged Frog Critical Habitat 

California Red-legged Frog Distribution 

Presumed Extinct 

Presumed Extant 

California Red-legged Frog CNDDB Records 
Specific Location 
O Approximate Location 
General Area 

Note: Project area maps provide a general description of 
work type and area for the 2012-2022 SMP and are not 
intended to represent the exact locations of future work. 


Merced County 



San Benito County 



H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-15: Projected Instream Herbicide Application in Areas of Potential California Red-legged Frog Occurrence, 2012-2022 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 














































This page intentionally left blank. 




LEGEND 

Santa Clara County Boundary 
SMP Project Area 

New Non-Instream Herbicide Application within 
Potential CRLF Range, 2012-2022 
Non-Instream Herbicide Application within Potential 
CRLF Range, both 2002-2012 and 2012-2022 


'////, California Red-legged Frog Critical Habitat 
California Red-legged Frog Distribution 
Presumed Extinct 
Presumed Extant 

California Red-legged Frog CNDDB Records 
• Specific Location 
O Approximate Location 
General Area 


Note: Project area maps provide a general description of 
work type and area for the 2012-2022 SMP and are not 
intended to represent the exact locations of future work. 


Merced County 





H. T. HARVEY & ASSOCIATES 


San Benito County 


Figure 3.3-16: Projected Non-Instream Herbicide Application in Areas of Potential California Red-legged Frog Occurrence, 2012-2022 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 


ECOLOGICAL CONSULTANTS 












































This page intentionally left blank. 



N:\Projects3000\3166-01\Reports\EIR June 2011 


LEGEND 

Santa Clara County Boundary 
SMP Project Area 

New Manual Vegetation Management within Potential CRLF 
Range, 2012-2022 

Manual Vegetation Management within Potential CRLF Range, 
both 2002-2012 and 2012-2022 

California Red-legged Frog Critical Habitat 

California Red-legged Frog Distribution 

Presumed Extinct 

Presumed Extant 

California Red-legged Frog CNDDB Records 
• Specific Location 


Note: Project area maps provide a general description of work type 
and area for the 2012-2022 SMP and are not intended to represent 
the exact locations of future work. 



Merced County 



H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-17: Projected Manual Vegetation Management in Areas of Potential California Red-legged Frog Occurrence, 2012-2022 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 









































This page intentionally left blank. 



3.3 Biological Resources 


USEPA has conducted ecological risk assessments to determine the potential risks of 
labeled uses of several herbicides, including four proposed for use by SCVWD (glyphosate, 
imazapyr, pendimethalin, and triclopyr], on the federally listed California red-legged frog. 
Evaluated herbicides proposed for use by SCVWD are as follows, with a summary of 
USEPA's effects determination: 

■ Glyphosate: Likely to adversely affect aquatic-phase California red-legged frog via 
indirect effects through reduction in prey (non-vascular plants] and habitat 
(aquatic and terrestrial plants]. There are no direct effects on the aquatic-phase 
California red-legged frog for any of the terrestrial or aquatic uses. Likely to 
adversely affect the terrestrial-phase California red-legged frogs via both direct 
effects and indirect effects following reduction in prey (terrestrial invertebrates, 
terrestrial-phase amphibians and mammals] and habitat (terrestrial plants]. 
Further, glyphosate is predicted to result in modification to RLF critical habitat. 

■ Imazapyr: Likely to adversely affect the California red-legged frog via indirect 
effects on habitat and/or primary productivity (i.e., ecosystem structure and 
function for both the aquatic plant community and riparian vegetation]. Critical 
habitat may also be modified. No direct effects are anticipated. 

■ Pendimethalin: Likely to adversely affect the California red-legged frog via both 
direct and indirect effects on both terrestrial and aquatic phases of the California 
red-legged frog. Critical habitat may also be modified. 

■ Triclopyr: Likely to adversely affect the California red-legged frog via both direct 
and indirect effects on both terrestrial and aquatic phases of the California red- 
legged frog. Critical habitat may also be modified. 

SCVWD would use a surfactant to enhance the performance of herbicides. Surfactants aid 
the ability of an herbicide to penetrate the surface of vegetation by increasing its ability to 
spread over vegetation, stick to foliage, and penetrate thick cuticles. Most aquatic 
herbicides either require or highly recommend the use of a surfactant to achieve 
reasonable levels of control. In instances where surfactants are absent from the tank mix, 
the level of control often is reduced. A reduction in control would cause a greater return 
frequency, which would translate to more herbicide being used in the system and more 
frequent disturbance to the site. 

In general, aquatic species (e.g., fish and amphibians] are more susceptible to adverse 
effects than terrestrial wildlife because of the potential for surfactants to alter cell 
permeability, thus increasing the potential for absorption of chemicals through their thin, 
moist skin. Some surfactants, particularly those that are nonylphenol-based, have been 
documented to result in chemical-induced lethargy and unconsciousness in fish, which can 
result in an increased risk of predation as well as have estrogenic effects (Smith et al. 2004, 
USFS 2007], However, SCVWD proposes to limit surfactant use of products documented to 
have the least toxic affect to aquatic life, Agri-dex and Competitor. Both of these surfactants 
are oil-based (Competitor is vegetable oil-based and the primary ingredient in Agri-dex is a 
paraffin-based oil] and function by increasing the absorption of herbicides through plant 
tissues. They are especially useful in increasing the penetration of herbicides through the 
bark of woody brush or tree stems (Bakke 2007]. A study on the toxicity of surfactants to 
juvenile rainbow trout concluded that Agri-dex was less toxic to rainbow trout than two 
other commonly used surfactants, R-ll and LI 700 (Smith et al. 2004], and the 2006 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-127 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Supplemental Environmental Assessment of NOAA Fisheries Implementation Plan for the 
Community Based Restoration Program (NOAA 2006] concluded that Agri-dex was among 
the surfactants least toxic to marine and aquatic organisms (it is unknown whether 
Competitor was assessed]. 

Although USEPA has determined that the pesticides listed above are likely to affect 
adversely the California red-legged frog, formal consultation between USEPA and USFWS 
has not been completed. Therefore, USEPA has not yet concluded whether each of these 
pesticides' registration, label, or use instructions needs to be altered so that use of a 
pesticide will not take or jeopardize the continued existence of the California red-legged 
frog. SCVWD would continue to use herbicides in compliance with existing applicable state 
and federal laws and in accordance with the voluntary guidelines established in the 
PRESCRIBE database managed by the California Department of Pesticide Regulation, which 
restricts the use of pendimethalin and triclopyr in habitat occupied by the California red- 
legged frog. 

In addition, SCVWD would follow the herbicide use guidelines established in its quality and 
environmental management system documents, including Q751D02 ( Control of Oversight 
of Pesticide Use ] and WW75100 ( Vegetation Control Work Instructions), and the 2012 SMP 
Manual (Appendix A], These guidelines require that all use of herbicide have the 
appropriate biological surveys and clearances and that all herbicide applications have a 
pest control recommendation, provided by a California licensed pest control advisor. A 
recommendation is provided after each site is surveyed and the most appropriate control 
methods for the site are determined. Furthermore, to minimize the potential for direct 
impacts of herbicides on California red-legged frogs, aquatic herbicides can only be used in 
areas of suitable red-legged frog habitat when the creek is dry and no rain is forecast for 
the next 48 hours (i.e., when these semi-aquatic species are unlikely to be present]. 

Critical habitat has been designated for the California red-legged frog (Figure 3.3-13], 
Projected activities have the potential to affect approximately 1.10 acres of designated 
critical habitat for the species in ways described above and under Determination of Impacts 
to Wildlife and Fisheries. Specifically, Proposed Project activities could affect the PCEs of 
critical habitat involving aquatic breeding and non-breeding habitat, upland habitat, and 
dispersal habitat for the California red-legged frog, as described generally for habitat 
impacts above. However, adverse effects of Proposed Project activities on red-legged frog 
critical habitat would be limited to very small areas near the northern end of Coyote 
Reservoir and the junction of Dexter Creek and Coyote Creek. 

SCVWD would implement the following BMPs to reduce impacts to individual California 
red-legged frogs and their habitats. A description of each BMP is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-2: Instream Herbicide Application Work Window 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-8: Protection of Sensitive Fauna Species from Herbicide Use 

BMP GEN-12: Protection of Special-Status Amphibian and Reptile Species 

BMP GEN-15: Salvage Native Aquatic Vertebrates from Dewatered Channels 

BMP GEN-20: Erosion and Sediment Control Measures 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-128 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-33: Dewatering for Non-Tidal Sites 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 

BMP VEG-3: Use Appropriate Equipment for Instream Removal 

BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 

BMP BANK-2: Concrete Use near Waterways 

BMP ANI-1: Avoid Redistribution of Rodenticides 

BMP ANI-4: Animal Control in Sensitive Amphibian Habitat 

Conclusion 

Implementation of these BMPs would reduce impacts California red-legged frog and its 
habitat. However, residual impacts to the California red-legged frog would remain because 
complete avoidance of impacts to this species and its habitat could not be avoided. Because 
of the regional rarity of the California red-legged frog, any impacts to this species and its 
habitats would be considered significant (Significance Criteria A, B, and E], Implementation 
of Mitigation Measure BIO-11 would reduce the impact to the California red-legged frog to 
a less-than-significant level. 

As discussed under Impacts BIO-1 and BIO-2, Mitigation Measure BIO-1 and Mitigation 
Measure BIO-2 would require SCVWD to provide compensatory mitigation for impacts to 
wetland, aquatic, and riparian habitats. This mitigation may take a variety of forms, and 
not all of this mitigation would occur in areas where California red-legged frog occurred. 
However, Mitigation Measure BIO-1 and Mitigation Measure BIO-2 could result in benefits 
to red-legged frog through wetland and riparian habitat restoration and the protection and 
management of mitigation lands that may support this species. Nevertheless, Mitigation 
Measure BIO-11 would be implemented to reduce the impact on the California red-legged 
frog and its habitat to a less-than-significant level. 

Mitigation Measure BIO-11: Implement Compensatory Mitigation for the 
California Red-Legged Frog 

SCVWD will provide mitigation to compensate for unavoidable impacts to California red- 
legged frogs and their habitat. SCVWD would refine the quantification of impacts to 
California red-legged frog habitat on an annual basis. At the end of each year's 
maintenance period, SCVWD will determine the extent of impacts to lands that are both 
within the potential range of the California red-legged frog and within potentially suitable 
habitat for the species. To determine whether the SMP impacts are within the potential 
range of the species, SCVWD will rely on the mapping in Figure 3.3-13 (which may be as 
modified over the course of 2012-2022, based on any new information that may modify 
the understanding of the species' potential range in the Project Area], To determine habitat 
suitability, an SCVWD biologist will determine whether the impact areas support land uses 
that are not conducive to California red-legged frog use, such as developed lands; all other 
land uses will be considered potential California red-legged frog habitat. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-129 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Compensation for these effects will be provided via the protection, enhancement, and 
management of habitat that currently supports, or could support, this species at a 2:1 
( mitigation: impact :mitigation ) ratio, on an acreage basis. Compensatory mitigation may be 
carried out through one or both of the following methods, in order of preference: 

» The preservation, management, and enhancement (e.g., through long-term 
management targeted toward this species] of high-quality habitat that is 
already occupied by California red-legged frogs 

■ The restoration or enhancement of degraded habitat or habitat that is 
unsuitable for use by California red-legged frogs, but that (a] is in close 
proximity to areas of known occurrence and (b] could be made more 
suitable for use via construction of one or more breeding ponds, 
enhancement of breeding and non-breeding aquatic habitat via 
improvements to emergent vegetation or other cover, or management to 
improve the quality of upland habitat 

Because much of the impact to California red-legged frog habitat will consist of 
modification of upland refugial/dispersal habitat (rather than aquatic breeding or foraging 
habitat! the mitigation lands will include upland habitat for this species. All mitigation 
lands for this species must be located within Santa Clara County and within the area where 
the species is thought to be extant as shown in Figure 3.3-13 (or as otherwise modified 
over the course of 2012-2022, based on any new information that may modify the 
understanding of the species' potential range in the Project Area], SCVWD will develop an 
HMMP describing the measures that will be taken to manage the property and to monitor 
the effects of management on the California red-legged frog; the HMMP will include 
components similar to those described for California tiger salamanders , including the 
maintenance or improvement of habitat conditions and components fi.e.. refugia in 
dispersal habitat] . Determining other specific performance/success criteria for this 
mitigation requires information regarding the specific mitigation site, its conditions, and 
the specific enhancement and management measures tailored to the mitigation site and its 
conditions. For example, performance criteria for a mitigation site providing only upland 
habitat for California red-legged frogs would include the maintenance of grassland habitat 
of a suitable height and density for use by dispersing frogs, whereas a mitigation site 
providing red-legged frog breeding habitat would also include criteria related to adequate 
depth and hydroperiod of breeding habitat and suitable vegetative cover. As a result, thos e 
additional specific criteria will be defined in the HMMP rather than in this SEIR. 
Nevertheless, the performance/success criteria described in the HMMP will guide the 
mitigation to manage and protect high-quality habitat for the California red-legged frog, 
adequate to compensate for impacts. 

After mitigation has been provided for impacts to a specific area supporting the California 
red-legged frog from a specific year's activities, future (i.e., repetitive] impacts to that area 
will not require additional mitigation. 

The HMMP will be provided to the USFWS for review because the California red-legged 
frog is a federally listed species regulated by the USFWS. It is possible that this mitigation 
measure may be refined during the Section 7 consultation process with the USFWS (e.g., in 
the Biological Opinion covering Project effects on the California red-legged frog], in which 
case the refinements required by the USFWS would be implemented. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-130 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


MM BIO-11 will mitigate impacts to the California red-legged frog to less-than-significant 
levels by enhancing, managing, and protecting habitat for this species so as to protect its 
populations, thereby ensuring that the SMP does not substantially reduce the number or 
restrict the range of this threatened species, have a substantial adverse effect on this 
special-status species, or impede the use of its nursery sites. 

Impact BIO-13: Impacts on the Foothill Yellow-Legged Frog 
(Significance Criteria A, B, and E; Less than Significant) 

The foothill yellow-legged frog is a California species of special concern. Like the California 
red-legged frog discussed under Impact BIO-12, it is associated with aquatic habitats in the 
Project Area. The types of impacts that could occur to foothill yellow-legged frog and the 
mechanisms by which these impacts could occur would be very similar to those described 
under Determination of Impacts to Wildlife and Fisheries and to those described for the 
California red-legged frog; thus, those impacts are not repeated here. However, the foothill 
yellow-legged frog’s distribution in the Project Area (Figure 3.3-18] is even more limited 
than that of the red-legged frog. Figure 3.3-18 depicts all projected activities relative to the 
expected distribution of this species in the Project Area, based on known occurrences 
(primarily from CNDDB 2011] and habitat suitability. As shown in this figure, the foothill 
yellow-legged frog is absent from all but a very small proportion of the areas where 
activities are projected. Yellow-legged frog is expected to occur primarily above the 
reservoirs along creeks, and thus activities associated with stream gauges (such as limited 
sediment removal and vegetation management], and possibly minor maintenance 
activities, would be the main activities that could affect yellow-legged frog. 

Table 3.3-4819 indicates the linear miles of creek in which sediment removal activities are 
projected in potential foothill yellow-legged frog habitat, and Table 3.3-4820 indicates the 
acreage of projected s e dim e nt r e moval vegetation management in potential foothill yellow¬ 
legged frog habitat. As shown in these tables, impacts to areas where this species may 
occur would be very limited. Since 2004, SCVWD has conducted annual surveys for the 
presence or absence of amphibians in numerous locations before the application of 
instream herbicides (see Table 3.3-3]; yellow-legged frogs have never been found at any of 
the locations listed in Table 3.3-3, suggesting that the distribution of these species in and 
near the Project Area is so limited that impacts would be very low. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-131 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Table 3.3-4&19. Projected Sediment Removal Impacts in Areas of Potential Foothill Yellow¬ 
legged Frog Occurrence, 2012-2022 


Creek/River 

Sediment Removal Impacts, 
2012-2022 
(miles) 

Bodfish Creek 

0.02 

Coyote Creek 

0.28 

Guadalupe Creek 

0.16 

Llagas Creek 

0.11 

Uvas-Carnadero Creek 

<0.01 

Total 

0.57 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 

Table 3.3-4^20. Projected Vegetation Management Impacts in Areas of Potential 


Foothill Yellow-legged Frog Occurrence, 2012-2022 


Creek/River 

Vegetation Management 
Impacts, 2012-2022 


(ac) 


Instream Herbicide Application 


Coyote Creek 

0.18 

Guadalupe Creek 

0.09 

Llagas Creek 

<0.01 

Uvas-Carnadero Creek 

0.03 

Total 

0.30 


Manual Vegetation Management 


Bodfish Creek 

0.16 

Coyote Creek 

0.92 

Guadalupe Creek 

0.09 

Llagas Creek 

0.09 

Uvas-Carnadero Creek 

0.37 

Total 

1.63 


Source: Data compiled by Horizon Water and Environment in 2011 based on information from 
SCVWD 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-132 


December 2011 
Project No. 10.005 




N:\Projects3000\3166-01\Reports\EIR June 2011 



© 


H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-18: Known and Expected Foothill Yellow-legged Frog Distribution in Santa Clara County 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 













































■queiq qjaj Xueuopusiui sSed siqj. 



3.3 Biological Resources 


SCVWD would implement the following BMPs to reduce impacts to individual foothill 
yellow-legged frogs and their habitats. A description of each BMP is provided in 
Table 2-12. 

Applicable Best Management Practices 

BMP GEN-2: Instream Herbicide Application Work Window 
BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-8: Protection of Sensitive Fauna Species from Herbicide Use 

BMP GEN-12: Protection of Special-Status Amphibian and Reptile Species 

BMP GEN-15: Salvage Native Aquatic Vertebrates from Dewatered Channels 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-33: Dewatering for Non-Tidal Sites 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 

BMP VEG-3: Use Appropriate Equipment for Instream Removal 

BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 

BMP BANK-2: Concrete Use near Waterways 

BMP ANI-1: Avoid Redistribution of Rodenticides 

BMP ANI-4: Animal Control in Sensitive Amphibian Habitat 

Conclusion 

Implementation of BMPs would reduce impacts to individual foothill yellow-legged frogs 
and their habitats considerably. Impacts would occur in such limited areas in which the 
species could be present, thus affecting such a low number of individuals that 
implementing these BMPs would be adequate to assure impacts would be less-than- 
significant. 

Although no mitigation would be needed to reduce the impact to foothill yellow-legged 
frog to a less-than-significant level, a number of mitigation measures for other impacts 
would benefit this species. As discussed under Impacts BIO-1 and BIO-2, Mitigation 
Measure BIO-1 and Mitigation Measure BIO-2 would require SCVWD to provide 
compensatory mitigation for impacts to wetland, aquatic, and riparian habitats. This 
mitigation may take a variety of forms, and not all such mitigation would occur in areas 
that would directly benefit the yellow-legged frog. However, Mitigation Measure BIO-1 and 
Mitigation Measure BIO-2 would result in wetland, aquatic, and riparian habitat 
restoration, enhancement, and protection, which would benefit the yellow-legged frog in 
areas where these mitigation measures would overlap with the yellow-legged frog's 
current range. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-133 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Impact BIO-14: Impacts on Non-Special-Status Fish and Amphibians 
(Significance Criteria A and E; Less than Significant with Mitigation) 

As discussed in Section 3.3.3, Environmental Setting, the rivers and creeks of Santa Clara 
County are home to 12 native species of fish (SCVWD 1995, Leidy 2007], In addition to the 
special-status fish mentioned under Impacts BIO-8, 9, and 10, native fish such as the 
California roach, hitch, Sacramento sucker, threespine stickleback, and others are present 
in the Project Area. 

Small numbers of the fall-run Chinook salmon also are known to occur in the Project Area, 
in Coyote Creek, Los Gatos Creek, and the Guadalupe River (Leidy et al. 2003], This species 
uses the lower reaches of Coyote Creek and Alviso Slough as migration corridors between 
estuarine habitats and upstream spawning and rearing habitats. However, genetic analysis 
has confirmed that Chinook in South Bay streams are all derived from hatchery stock 
(Hedgecock 2002], and conditions for successful spawning in the Project Area are marginal 
because of low water levels in the creeks in fall, when this species typically spawns. 
Likewise, several species of non-special-status amphibians, such as the western toad and 
Pacific chorus frog use Project Area creeks as breeding and foraging habitat. 

Various Proposed Project activities would impact non-special-status fish and amphibians 
in the Project Area, in ways described under Determination of Impacts to Wildlife and 
Fisheries. The non-special-status fish and amphibians that would be impacted by the 
Proposed Project are relatively abundant and widespread, with the exception of the 
Chinook salmon, which is not native to South Bay streams. As a result, any one 
maintenance activity would not result in a substantial effect on regional populations. 
However, over the entire geographic and temporal scope of the SMP Update, Proposed 
Project activities could have the potential to impact relatively large numbers of non¬ 
special-status fish and amphibians, which would result in modifications to extensive areas 
of their habitats. In addition, mitigation activities such as gravel augmentation (Mitigation 
Measure BIO-8] and installation of instream complexity (Mitigation Measure BIO-9] could 
result in impacts to aquatic species during installation; however, the net effect of these 
measures on fish and amphibians would be beneficial. 

When performing any type of maintenance activity that would necessitate work within or 
adjacent to the active channel, SCVWD would implement BMPs to reduce impacts to water 
quality (e.g., erosion and sediment control, spill prevention, standard herbicide 
requirements]. In addition, implementation of BMPs related to dewatering of work sites 
would assure that, before dewatering, the best means to bypass flow through a work site 
would be determined, to minimize disturbance to the channel and avoid direct mortality of 
fish. Sediment removal BMPs would assure that low-flow channels within non-tidal 
streams were configured with the appropriate depth for fish passage. All the BMPs that 
would be implemented to reduce impacts to non-special-status fish and amphibians are as 
follows, and a description of each is provided in Table 2-12. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-134 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Applicable Best Management Practices 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-2: Instream Herbicide Application Work Windows 

BMP GEN-15: Salvage Native Aquatic Vertebrates from Dewatered Channels 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-236: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-32: Dewatering for Non-Tidal Sites 

BMP GEN-34: Dewatering in Tidal Work Areas 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP SED-3: Restore Channel Features 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 
BMP VEG-3: Use Appropriate Equipment for Instream Removal 
BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 
BMP BANK-2: Concrete Use near Waterways 

Conclusion 

Implementation of these BMPs would reduce impacts to populations and habitat of non¬ 
special-status fish and amphibians. However, residual impacts would remain. Because of 
the broad scope of the SMP Update—the number of these species that would be affected 
directly and indirectly, and the extent of habitat impacts—the collective Proposed Project 
activities would have the potential to substantially affect the population. Thus, impacts to 
individuals and their habitats resulting from the Proposed Project would be significant 
(Significance Criterion A}. 

As discussed under Impacts BIO-1 and BIO-2, Mitigation Measure BIO-1 and Mitigation 
Measure BIO-2 would require SCVWD to provide compensatory mitigation for impacts to 
wetland, aquatic, and riparian habitats. This mitigation may take a variety of forms, but all 
potential mitigation for impacts to those habitats would benefit non-special-status fish or 
amphibians, either directly or indirectly. Mitigation Measure BIO-1 and Mitigation Measure 
BIO-2 would result in benefits to these species through wetland, aquatic, and riparian 
habitat restoration, enhancement, and protection, which would help to maintain water 
quality, cover, and instream habitat complexity for them. In addition, implementation of 
Mitigation Measure BIO-9 would increase instream complexity, and thus would be 
expected to benefit non-special-status fish or amphibians in a manner similar to that 
described for steelhead. Mitigation Measure BIO-1, Mitigation Measure BIO-2, and 
Mitigation Measure BIO-9 would be implemented to reduce the impact to non-special- 
status fish and amphibians to a less-than-significant level. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-135 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Impact BIO-15: Impacts on Essential Fish Habitat 
(Significance Criteria A and D; Less than Significant) 

As noted in Section 3.3.2, Regulatory Setting, the only fish species subject to a fisheries 
management plan that occurs in the Project Area with any regularity is the Chinook 
salmon, which is regulated by the Pacific Fishery Management Council's Salmon Fishery 
Management Plan (Pacific Fishery Management Council 1999], Although the Chinook 
salmon in the Project Area have been recognized as strays from hatchery releases (NMFS 
1999, Hedgecock 2002], NMFS still considers habitat used by Chinook salmon in the South 
Bay as EFH. 

Several fish species regulated by the Pacific Groundfish Fisheries Management Plan (Pacific 
Fishery Management Council 2008], such as the leopard shark, English sole, starry 
flounder, and big skate, occur in tidal habitats of South San Francisco Bay and occasionally 
disperse upstream into the reaches of Alviso Slough, Coyote Slough, Guadalupe Slough, 
Stevens Creek, San Francisquito Creek, Lower Penitencia Creek, Permanente Creek, 
Sunnyvale East and West Channels, and San Tomas Aquino Creek in the Project Area. Fish 
regulated by the Coastal Pelagics Fisheries Management Plan (Pacific Fishery Management 
Council 1998], such as the northern anchovy, Pacific sardine, and jack mackerel also occur 
in the South Bay but are less likely to occur in the uppermost tidal reaches of sloughs 
where Proposed Project activities would take place. Because of the presence of at least 
some species managed by one of these plans, these tidal waters possibly could be 
considered EFH. 

The types of effects that Proposed Project activities could have on Chinook salmon and 
associated EFH that would support these species are the same as those described for 
steelhead under Impact BIO-8, with the caveat that only the impacts to CCC steelhead, 
occurring in the Santa Clara Basin would apply to Chinook salmon. Chinook salmon 
historically did not spawn in streams flowing into South San Francisco Bay. Since the mid- 
1980s, however, small numbers of fall-run Chinook salmon have been found in several 
such streams, including Coyote Creek, Los Gatos Creek, and the Guadalupe River in the 
Project Area (Leidy et al. 2003], However, genetic analysis, timing of spawning, and the 
detection of coded, wire-tagged hatchery fish in the Project Area suggest that these fish are 
derived from Central Valley fall-run stock (Garcia-Rossi and Hedgecock 2002], possibly 
hatchery releases. Conditions for successful spawning in the Project Area would be 
marginal because these fish spawn during fall when streamflow is at its lowest. As a result, 
up-migrating adults would have difficulty accessing spawning areas. Although spawning 
has been documented in SCVWD-maintained creeks, whether up-migrating adults have 
hatched on these creeks or if the adults that were observed were direct strays from other 
areas is unknown. Thus, no evidence exists that Chinook salmon have become naturalized 
in the Project Area. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-136 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Proposed Project activities would have limited effects on potential EFH in tidal waters, but 
such impacts may occur because of both projected sediment removal and vegetation 
management activities and unprojected activities (e.g., bank stabilization and minor 
maintenance]. Sediment removal would occur in tidal areas only in the uppermost reach of 
Alviso Slough. Sediment removal activities would actually increase the extent of aquatic 
habitat for a few years, until sediment accumulation once again created wetlands within 
these aquatic habitats. However, during sediment removal, turbidity may increase, 
potentially affecting the health or foraging ability of fish in tidal waters. 

Vegetation management activities would occur more widely adjacent to tidal waters; such 
activities would occur along San Francisquito Creek, the Sunnyvale West Channel, Moffett 
Channel, Guadalupe Slough, Coyote Slough, Alviso Slough, San Tomas Aquino Creek, and 
Permanente Creek. Some potential would exist for water-quality impacts caused by drift of 
herbicides into tidal sloughs containing EFH. Degradation of water quality may be 
particularly detrimental to young fish of species that use South Bay sloughs as nursery 
habitat. 

Vegetation management activities in and adjacent to tidal sloughs would not result in a 
loss of EFH, although some vegetation removal would occur, causing a minor loss of habitat 
structure. Sediment removal areas within tidal channels projected from 2012-2022 would 
include only a very small amount of tidal channel that was not already impacted (and those 
impacts compensated for] from 2002-2012; this reach occurs in the Guadalupe River 
upstream from Gold Street. The reach of tidal channel in this area is short, and sediment 
removal from this area would not result in the loss of EFH. Therefore, no significant loss of 
EFH would occur. 

The effects of Proposed Project activities on EFH and fish species regulated by the Coastal 
Pelagics and Pacific Groundfish Fisheries Management plans would not be substantial 
because of the limited overlap of Proposed Project activities with tidal waters. 
Furthermore, SCVWD would implement of the following BMPs to reduce impacts to fish 
and their habitat, including EFH; a description of each BMP is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-1: In-Channel Work Window 

BMP GEN-2: Instream Herbicide Application Work Window 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-8: Protection of Sensitive Fauna Species from Herbicide Use 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-33: Dewatering for Non-Tidal Sites 

BMP GEN-34: Dewatering in Tidal Work Areas 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 
BMP VEG-3: Use Appropriate Equipment for Instream Removal 
BMP BANK-2: Concrete Use near Waterways 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-137 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Conclusion 

Implementation of these BMPs would reduce impacts to EFH and associated fish species 
considerably. Because no evidence exists that Chinook salmon have naturalized in SCVWD- 
maintained creeks, Proposed Project activities are not expected to affect adversely the 
viability of this species' populations in the Project Area. As a result, with implementation of 
these BMPs, impacts on this species would be less than significant. Likewise, these BMPs 
would be adequate to assure the impacts to EFH and associated species in tidal areas 
would be less-than-significant. 

Although no mitigation would be needed to reduce impacts to EFH to less-than-significant 
levels, a number of mitigation measures for other impacts would benefit EFH and 
associated species. As discussed under Impacts BIO-1 and BIO-2, Mitigation Measure BIO-1 
and Mitigation Measure BIO-2 would require SCVWD to provide compensatory mitigation 
for impacts to wetland, aquatic, and riparian habitats. This mitigation may take a variety of 
forms, and not all such mitigation would occur in areas that would directly benefit EFH or 
associated species. However, Mitigation Measure BIO-1 and Mitigation Measure BIO-2 
would result in benefits to fish through wetland, aquatic, and riparian habitat restoration, 
enhancement, and protection, which would help to maintain water quality, cover, and 
instream habitat complexity for these species. Mitigation Measure BIO-1 would 
incorporate a tidal wetland mitigation component that would benefit EFH species. In 
addition, implementation of Mitigation Measure BIO-8 would compensate for impacts to 
steelhead spawning gravel, which also would provide potential spawning habitat for the 
Chinook salmon. Mitigation Measure BIO-9 would increase instream complexity, and thus 
would be expected to benefit Chinook salmon in a manner similar to that described for 
steelhead. 

Impact BIO-16: Impacts on the Western Pond Turtle 

(Significance Criteria A, B, and E; Less than Significant with Mitigation) 

Suitable habitat for the western pond turtle (a California species of special concern] 
consists of ponds or instream pools (i.e., slack water environments] with available basking 
sites, nearby upland areas with clay or silty soils for nesting, and shallow aquatic habitat 
with emergent vegetation and invertebrate prey for juveniles (Jennings and Hayes 1994], 
In the Project Area, all perennial creeks, many intermittent creeks, and most ponds (those 
not completely isolated by development] have some potential to support the western pond 
turtle. Figure 3.3-19 shows the known locations of this species in the county. Impacts of 
proposed stream maintenance activities may affect aquatic habitat used by western pond 
turtles for foraging or dispersal, upland habitat used for nesting, and individuals or 
populations of the species. 

As described under Determination of Impacts to Wildlife and Fisheries, and similar to the 
California red-legged frog impact discussion, proposed maintenance activities may result 
in the injury or mortality of turtles. For example, individual turtles or their eggs may be 
directly harmed or killed during maintenance activities from crushing by construction 
personnel or equipment or as a result of desiccation or burying. Such impacts may occur 
because of both projected sediment removal and vegetation management activities and 
unprojected activities (e.g., bank stabilization, management of animal conflicts, and minor 
maintenance]. In addition, riparian and upland areas that provide nesting habitat, 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-138 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


dispersal habitat, and refugia for western pond turtles may be temporarily or permanently 
lost during bank stabilization activities and the construction of temporary stream access 
routes. Activities requiring dewatering also would result in a temporary loss of aquatic 
habitat. Vegetation management may reduce instream habitat structure, including basking 
areas, vegetation that provides concealment from predators, and habitat that supports 
turtle prey. Mitigation activities such as gravel augmentation (Mitigation Measure BIO-8] 
and installation of instream complexity (Mitigation Measure BIO-9] could result in impacts 
to western pond turtles during installation; however, the net effect of these measures on 
turtles would be beneficial. 

When performing any type of maintenance that necessitated work within or adjacent to 
the active channel, SCVWD would implement BMPs (listed below] to reduce impacts to 
water quality (e.g., erosion and sediment control, spill prevention, and standard herbicide 
requirements]. Implementation of BMPs related to dewatering of work sites would assure 
that, before dewatering, the best means to bypass flow through a work site would be 
determined, to minimize disturbance to the channel and avoid direct mortality of aquatic 
animals. In addition, by implementing BMPs GEN-12 and GEN-15, western pond turtles 
would be relocated from the work site before the onset of maintenance activities. 
However, individuals that were found during pre-activity surveys and relocated to suitable 
habitat outside of the work site may be subjected to physiological stress and greater risk of 
predation, or may undergo increased competition with turtles already present in the area 
to which they were relocated. 

SCVWD would implement of the following BMPs to reduce impacts to western pond 
turtles. A description of each BMP is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-2: Instream Herbicide Application Work Window 
BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-8: Protection of Sensitive Fauna Species from Herbicide Use 

BMP GEN-12: Protection of Special-Status Amphibian and Reptile Species 

BMP GEN-15: Salvage Native Aquatic Vertebrates from Dewatered Channels 

BMP GEN-20: Erosion and Sediment Control Measures 

BMP GEN-23: Stream Access 

BMP GEN-26: Spill Prevention and Response 

BMP GEN-30: Vehicle and Equipment Maintenance 

BMP GEN-32: Vehicle and Equipment Fueling 

BMP GEN-35: Pump/Generator Operations and Maintenance 

BMP SED-2: Prevent Scour Downstream of Sediment Removal 

BMP VEG-1: Minimize Local Erosion Increase from In-Channel Vegetation Removal 

BMP VEG-3: Use Appropriate Equipment for Instream Removal 

BMP BANK-1: Bank Stabilization Design to Prevent Erosion Downstream 

BMP BANK-2: Concrete Use near Waterways 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-139 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Conclusion 

Implementation of these BMPs would reduce impacts to western pond turtles and their 
habitats. However, residual impacts would remain because it would not be feasible to 
avoid all individuals (particularly nests with eggs] and habitat loss while still meeting 
project goals and public health and safety directives. Although western pond turtles are 
widespread in the Project Area, the species is not particularly abundant there. Because 
individuals of this species can be long-lived, the widespread nature of the species in the 
Project Area may belie a population that likely would decline substantially in the future 
because of poor reproduction, as young turtles are seen in relatively few parts of the 
Project Area. Therefore, the loss of individuals or of important aquatic or upland habitat 
could reduce the viability of a population to the extent that it would be extirpated. This 
impact would be considered significant (Significance Criteria A, B, and E). 

As discussed under Impacts BIO-1 and BIO-2, Mitigation Measure BIO-1 and Mitigation 
Measure BIO-2 would require SCVWD to provide compensatory mitigation for impacts to 
wetland, aquatic, and riparian habitats. This mitigation may take a variety of forms, but all 
mitigation for impacts to those habitats could benefit western pond turtle upland or 
aquatic habitat, directly or indirectly. Mitigation Measure BIO-1 and Mitigation Measure 
BIO-2 would result in benefits to this species through wetland, aquatic, and riparian 
habitat restoration, enhancement, and protection. These measures would help to maintain 
water quality, cover, and instream habitat complexity while protecting upland refugia and 
nesting habitat. In addition, implementation of Mitigation Measure BIO-9 would increase 
instream complexity; this complexity would include installation or improvement of large 
woody debris, instream flow wings, or other features that would compensate for the loss of 
turtle basking habitat as a result of the Proposed Project. Mitigation Measure BIO-1, 
Mitigation Measure BIO-2, and Mitigation Measure BIO-9 would be implemented to reduce 
the impact to the western pond turtle to a less-than-significant level. 

Impact BIO-17: Impacts on the California Homed Lizard 
(Significance Criteria A, B, and E; Less than Significant) 

The California horned lizard (a California species of special concern] is associated with a 
variety of open vegetation communities, including chaparral, coastal scrub, and annual 
grassland, as well as with clearings in riparian woodlands. These communities are 
characterized by sandy, loosely textured soils that are the lizards' preferred habitat 
(Jennings and Hayes 1994] and by the presence of native harvester ants (Pogonomyrmex 
barbatus ), which are a primary part of their diet (Fisher et al. 2002], However, suitable 
habitat is scarce in the Project Area, and the species has been recorded from very few 
areas near projected work sites (Figure 3.3-19], As a result, this species likely would be 
present only in very low numbers in areas where it could be impacted by Proposed Project 
activities. 

Nevertheless, some potential would exist for individuals of this species to be killed or 
injured during stream maintenance activities from crushing by construction personnel or 
equipment. Such impacts may occur because of both projected sediment removal and 
vegetation management activities and unprojected activities (e.g., bank stabilization, 
management of animal conflicts, and minor maintenance]. In addition, the introduction of 
non-native Argentine ants, the modification of habitats to favor these ants instead of native 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-140 


December 2011 
Project No. 10.005 



N:\Projects3000\3166-01\Reports\EIR June 2011 



© 


H. T. HARVEY & ASSOCIATES 

ECOLOGICAL CONSULTANTS 


Figure 3.3-19: Western Pond Turtle and California Horned Lizard CNDDB Occurrences in Santa Clara County 

Santa Clara Valley Water District Stream Maintenance Program EIR (3166-01) 

July 2011 






































■queiq qjaj Xueuopusiui sSed siqj. 



3.3 Biological Resources 


harvester ants, and the introduction of non-native or invasive plants that would degrade 
habitat quality may affect the species after maintenance activities were complete. 
However, the likelihood of such impacts would be extremely low because suitable habitat 
in the Project Area primarily occurs in uplands in less developed areas outside of stream 
maintenance work sites (with much more limited habitat in clearings within riparian 
areas]. Furthermore, populations of the California horned lizard in the Project Area are 
limited in number and extent, and few individuals likely would be present. This species 
occurs much more commonly just to the east in the interior of the Diablo Range, but only 
very sparingly on the fringes of the Project Area itself. Therefore, the Proposed Project 
would not have a substantial effect on regional populations of the species (which would 
include those in the Diablo Range], 

SCVWD would implement the following BMPs, to limit the area of disturbance and to 
protect special-status reptiles such as the California horned lizard. A description of each 
BMP is provided in Table 2-12. 

Applicable Best Management Practices 

BMP GEN-4: Minimize the Area of Disturbance 

BMP GEN-12: Protection of Special-Status Amphibian and Reptile Species 
Conclusion 

Implementation of these BMPs would be adequate to assure the potential impact to the 
California horned lizard would be less-than-significant. No mitigation would be required. 

Impact BIO-18: Impacts on the Black Skimmer 
(Significance Criteria A, B, and E; Less than Significant) 

The black skimmer (a California species of special concern] is associated with saline- 
managed pond habitats, which occur only in the northernmost portion of the Project Area. 
Black skimmers nest on small islands within managed ponds; this nesting habitat is 
ephemeral and thus is not mapped. Sediment management activities under the Proposed 
Project would not directly affect black skimmer nesting habitat. Similarly, proposed 
vegetation management activities are not expected to occur in suitable nesting habitat that 
currently exists, nor are vegetation management activities proposed in areas that are likely 
to be converted to suitable nesting habitat for this species in the next 10 years. Although 
herbicide application and mowing is projected to occur along levees adjacent to breeding 
habitat, because these activities would not occur in the managed pond habitat itself and 
would be of short duration in any specific area, they are not expected to disturb nesting 
skimmers to the point of nest abandonment. 

The only activities with some potential to affect nesting black skimmers would be minor 
maintenance activities. Although these activities are not projected, some road grading (e.g., 
along levee roads around saline managed ponds] or removal of sediment or debris at flap 
gates possibly could occur near nesting sites for this species. Thus, some potential would 
exist for minor maintenance activities to disturb nesting skimmers, possibly to the point of 
abandonment of eggs or young. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-141 


December 2011 
Project No. 10.005 



3.3 Biological Resources 


Conclusion 

SCVWD would implement BMP GEN-6 ( Minimize Impacts to Nesting Birds via Site 
Assessments and Avoidance Measures ] to minimize the potential for Proposed Project 
activities to impact nesting birds. With implementation of this BMP, no disturbance of 
nesting black skimmers is expected to occur. Therefore, the impact to this species would be 
less than significant, and no mitigation would be required. 

Impact BIO-19: Impacts on the Western Snowy Plover 
(Significance Criteria A, B, and E; Less than Significant) 

The western snowy plover (federally listed as threatened and a California species of 
special concern] is associated with non-tidal saline managed pond and salt panne habitats, 
which occur only in the northernmost portion of the Project Area. Figure 3.3-20 depicts the 
locations of potential (or recent] western snowy plover breeding habitat in the Project 
vicinity. 

No sediment removal is projected to occur in western snowy plover habitat. Similarly, 
vegetation management activities are not projected to occur in currently suitable nesting 
habitat or in areas that are likely to be converted to suitable nesting habitat for these 
species in the next 10 years. Although herbicide application and mowing are projected to 
occur along levees, these activities would occur along outboard levees (i.e., those along 
sloughs] that would not be used for nesting by snowy plovers in the Project Area. 

Although no activities are projected in or adjacent to habitat that is currently used by 
nesting snowy plovers, some potential would exist for Proposed Project activities to 
disturb nesting plovers. This species can select breeding areas opportunistically, and 
possible changes in habitat from 2012-2022 could result in use of new areas by breeding 
plovers. For example, if management of ponds adjacent to projected activities (such as 
Pond A4 between Moffett Channel and Guadalupe Slough, or Pond A18 adjacent to South 
Coyote Slough] changed so that these ponds became suitable for nesting, then plovers may 
nest in areas adjacent to projected activities. Minor maintenance road work and 
sediment/debris removal at flap gates, which are not projected activities, would occur in 
bayfront areas, and such activities potentially could occur along levees near breeding 
plovers. Sediment reuse, such as sediment disposal at the edges of managed ponds to 
provide upland transition zones for future tidal restoration, also may occur at the edges of 
ponds where snowy plovers could breed. Fikewise, if activities such as vegetation 
management or management of animal conflicts needed to occur in non-projected areas, 
such as segments of Alviso Slough along Pond A12, then Proposed Project activities could 
occur adjacent to snowy plover nesting and foraging habitat. Even in such cases, Proposed 
Project activities are not expected to alter directly snowy plover breeding habitat, and no 
long-term impacts from any Proposed Project activities would occur on snowy plovers. 


Santa Clara Valley Water District 

Stream Maintenance Program Update 

Final Subsequent Environmental Impact Report 


3.3-142 


December 2011 
Project No. 10.005 



N:\Projects3000\3166-01\Reports\EIR June 2011 



1 




SNIP Project Area 


LEGEND 


DETAIL MAP 


SMP Routes 


Santa Clara C