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Final Environmental Assessment Alternative Intake Project Transmission Line and Interconnection Final Environmental Assessment November 2008 DOE/EA-1602 DOE/EA-1602 Final Environmental Assessment for the Western Area Power Administration Alternative Intake Project Transmission Line and Interconnection As part of its comprehensive water quality strategy to protect and improve water quality for its customers, the Contra Costa Water District (CCWD) is implementing the Alternative Intake Project (AIP). The AIP will enable CCWD to relocate some of its existing diversions to Victoria Canal, a Delta location with higher-quality source water than is currently available at its Old River and Rock Slough intakes. The AIP project purpose is to protect and improve the quality of water delivered to CCWD’s untreated- and treated-water customers. Key objectives of the AIP are to improve delivered water quality, especially during drought periods; protect and improve health and/or aesthetic benefits to consumers; improve operational flexibility; and protect delivered water quality during emergencies. The AIP facilities include an intake and pump station, pipeline, and pipeline intertie, as well as construction and operations/maintenance of a new transmission line and interconnection. This Final Environmental Assessment (EA) evaluates Western Area Power Administration’s (Western’s) Transmission Line and Interconnection (Proposed Action) for the AIP. The Proposed Action would extend Western’s existing Tracy-Los Vaqueros 69-kilovolt (kV) transmission line from near CCWD’s existing Old River Pump Station, span Old River onto Victoria Island, and continue along existing dirt roads to the AIP’s new power substation serving the new CCWD Victoria Canal Pump Station. The Proposed Action would make the AIP a new point of delivery on Western’s system for delivery of power for pumping CCWD’s Central Valley Project (CVP) water and non- CVP water at the AIP. This arrangement would be similar to CCWD’s other intake facilities’ power deliveries with Western and would offset some of the existing power usage by CCWD at Old River Pump Station. The AIP would be a new point of delivery for project power. Western would be responsible for constructing, operating, and maintaining the Proposed Action. CCWD, together with the U.S. Department of the Interior, Bureau of Reclamation (Reclamation), prepared an Environmental Impact Report/Environmental Impact Statement (EIR/EIS) for the AIP to comply with the California Environmental Quality Act (CEQA) and the National Environmental Policy Act (NEPA), respectively. The EIR/EIS has State Clearinghouse Number 2005012101. The CCWD Board certified the EIR on November 15, 2006. This Final EA uses much of the information contained in the EIR/EIS but is focused solely on the potential environmental effects associated with the Proposed Action. For further information regarding the Final EA, please contact Cherie Johnston-Waldear, Western Area Power Administration, Sierra Nevada Region, 114 Parkshore Drive, Folsom, California 95630-4710 or phone at (916) 353-4035. Final Environmental Assessment for the Western Area Power Administration Alternative Intake Project Transmission Line and Interconnection Prepared by: Western Area Power Administration Sierra Nevada Region 114 Parkshore Drive Folsom, CA 95630-4710 Contact: Cherie Johnston-Waldear (916) 353-4035 With Assistance from: Contra Costa Water District 1331 Concord Avenue Concord, CA 94524 Contact: Scott Weddle (925) 688-8000 and U.S. Department of the Interior, Bureau of Reclamation Mid-Pacific Region 2800 Cottage Way Sacramento, CA 95825-1898 Contact: Sharon McHale (916) 978-5086 and EDAW 2022 J Street Sacramento, CA 95811 Contact: Phil Dunn (916) 414-5800 November 2008 Table of Contents ACRONYMS AND ABBREVIATIONS........................................................................ vi 1 PURPOSE AND NEED ........................................................................................... 1-1 1.1 Introduction and Background ........................................................................1-1 1.2 Purpose of and Need for Action.....................................................................1-4 1.3 Location and Study Area Description............................................................1-4 1.4 Scope of this Environmental Assessment......................................................1-6 1.5 Decisions Needed...........................................................................................1-7 2 ALTERNATIVES INCLUDING THE PROPOSED ACTION .......................... 2-1 2.1 Proposed Action.............................................................................................2-1 2.1.1 Description and Facilities............................................................... 2-1 2.1.2 Conservation Measures................................................................... 2-2 2.1.3 Construction Schedule.................................................................... 2-2 2.1.4 Operations and Maintenance........................................................... 2-2 2.2 No-Action Alternative...................................................................................2-3 2.3 Alternatives Considered but Eliminated from Detailed Analysis..................2-4 3 AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES .................................................................................................. 3-1 3.1 Resources ....................................................................................................3.1-1 3.1.1 Resources Evaluated .................................................................... 3.1-1 3.1.2 Resources Eliminated from Detailed Analysis ............................ 3.1-3 3.2 Land Use.....................................................................................................3.2-1 3.2.1 Affected Environment.................................................................. 3.2-1 3.2.2 Environmental Consequences...................................................... 3.2-2 3.3 Habitats and Vegetation..............................................................................3.3-1 3.3.1 Affected Environment.................................................................. 3.3-1 3.3.2 Environmental Consequences...................................................... 3.3-7 3.4 Wildlife .......................................................................................................3.4-1 3.4.1 Affected Environment.................................................................. 3.4-1 3.4.2 Environmental Consequences...................................................... 3.4-5 3.5 Fisheries ......................................................................................................3.5-1 3.5.1 Affected Environment.................................................................. 3.5-1 3.5.2 Environmental Consequences...................................................... 3.5-5 Western Area Power Administration Alternative Intake Project Transmission Line and Interconnection Final Environmental Assessment i Table of Contents (Continued) 3.6 Geology and Soils.......................................................................................3.6-1 3.6.1 Affected Environment.................................................................. 3.6-1 3.6.2 Environmental Consequences...................................................... 3.6-6 3.7 Air Quality..................................................................................................3.7-1 3.7.1 Affected Environment.................................................................. 3.7-1 3.7.2 Environmental Consequences...................................................... 3.7-8 3.8 Water Quality..............................................................................................3.8-1 3.8.1 Affected Environment.................................................................. 3.8-1 3.8.2 Environmental Consequences...................................................... 3.8-2 3.9 Public Health...............................................................................................3.9-1 3.9.1 Affected Environment.................................................................. 3.9-1 3.9.2 Environmental Consequences...................................................... 3.9-4 3.10 Recreation .................................................................................................3.10-1 3.10.1 Affected Environment................................................................ 3.10-1 3.10.2 Environmental Consequences.................................................... 3.10-2 3.11 Cultural Resources....................................................................................3.11-1 3.11.1 Affected Environment................................................................ 3.11-1 3.11.2 Environmental Consequences.................................................... 3.11-5 3.12 Aesthetics..................................................................................................3.12-1 3.12.1 Affected Environment................................................................ 3.12-1 3.12.2 Environmental Consequences.................................................... 3.12-6 3.13 Summary of Environmental Consequences..............................................3.13-1 3.13.1 Overview of the Environmental Effects of the Alternatives...... 3.13-1 3.13.2 No-Action Alternative Effects ..................................................
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