Pacheco Reservoir Expansion
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California Water Commission Pacheco Reservoir Expansion Unique Opportunity for Fisheries Recovery, Flood Risk Reduction and Emergency Water Supply December 13, 2017 PPWD 1 of 33 Project Partners Pacheco Creek Pacheco Pass Water District PPWD 2 of 33 Project Location Pacheco Expansion Existing Pacheco Reservoir PPWD 3 of 33 The Project Delivers a High Percentage of Public Benefits Emergency Response Ecosystem $455M 81% Improvement 31% Public Benefits $722M 50% Water Supply /Quality $282M 19% 2.43 Public Benefit Ratio PPWD 4 of 33 The Partners Seek to Address Five Big Challenges Restore Federally Improve the Improve Eliminate Reduce Threatened Fish Delta Resiliency and Water Quality Flooding to Emergency Issues in San Luis Disadvantaged Water Supply Reservoir Communities 90% population 90% of Delta 66% chance of Delta Water quality issues Extensive flooding decline in Pajaro watershed wetlands earthquake in next 50 during summer even for frequent/ watershed from have disappeared years; 45% of water supply months in 57% of small events; 1960s to 1990s imported from Delta years 20-year flood in 2017 (pictured) PPWD 5 of 33 The Reservoir Expansion will Provide Public Solutions PPWD 6 of 33 25 Enables Federally Threatened Steelhead 20 Recovery 15 The project will improve conditions in watershed critical to recovery 10 • Improves water flow in Pacheco Creek in Cohort Score Cohort all hydrologic conditions 5 • Larger cold water pool improves temperature in Pacheco Creek 0 Wet Above Below Dry Critical • Increases SCCC Steelhead cohort score Normal Normal between 162% (2030) and 178% (2070) Without Project With Project • Enables growth of an independent population in the Pajaro River watershed PPWD 7 of 33 Dry Pacheco Creek - August 2014 1.3 cfs flow - July 2016 Pacheco Creek will have enhanced flow PPWD 8 of 33 Enhances Bay-Delta Ecosystem Increased water supplies to Delta watershed refuges • Dedicates irrigation to wetlands in below-normal water years • Increases food supply for migrating Pacific Flyway waterfowl in the fall and winter PPWD 9 of 33 "California's last remaining 5% of wetlands are found on wildlife refuges in the Central Valley and are critical to the health of the millions of migratory birds using the pacific flyway each year. The Pacheco reservoir expansion project proposes to provide thousands of acre feet to these refuges in below normal water years when water supplies south of the delta are scarce and highly expensive to help maintain thousands of acres of this critical public trust.” Ric Ortega, Grassland Water and Resource Conservation Districts PPWD 10 of 33 Reduces Flooding in Disadvantaged Communities The project will protect disadvantaged and vulnerable communities against flooding • Decreases flood flows from North Fork Pacheco Creek by up to 61% • Reduces downstream 100-year flood flows by up to 4,700 cfs • With the new reservoir, 2017 flood flows in North Fork Pacheco Creek would have been fully contained Pictured above: Hollister 2014 flooding PPWD 11 of 33 Eliminates San Luis Low Point Water Quality Issues Algae Bloom in San Luis The project reduces operational Reservoir constraints at San Luis Reservoir Prevents 73 months of impaired water quality deliveries (2030) and 109 months (2070) by: • Delivering CVP supplies to the Pacheco Reservoir earlier in the season • Capturing Pacheco watershed supplies in the expanded reservoir • Using the Pacheco Reservoir as a blending source when needed. Thus, project operations will avoid spikes in taste and odor measuring 10 times normal levels, which cause problems in today’s domestic supply PPWD 12 of 33 Delta levee Emergency failure, Jones Tract Water Supply The project will provide dedicated emergency water supply • Increases emergency water supply in 2030 and 2070 by 82,000 and 87,000 acre-feet • Increases local surface storage capacity by 90% • Mitigates risk of Delta export outages and imported water conveyance outages PPWD 13 of 33 The Project will Enhance Water Supply for Agriculture and M&I The project will reduce drought risk to agricultural and M&I water users • Increases water supply by up to 20,000 acre-feet in dry years • Improves groundwater conditions to agricultural customers • Materially contributes to sustainable groundwater management goals in four basins PPWD 14 of 33 The Environmental Benefits are Compelling PPWD 15 of 33 High Relative Environmental Value -- Addresses 11 of 16 Ecosystem Priorities Provide cold water at times and locations Enhance flow regimes or groundwater P 1 to increase the survival of salmonid conditions to improve the quantity and Increase attraction flows during upstream ✔ eggs and fry. quality of riparian and floodplain P 6 migration to reduce straying of anadromous P 9 species into non-natal tributaries ✔ habitats for aquatic and terrestrial Provide flows to improve habitat conditions for species. P 2 in-river rearing and downstream migration of ✔ juvenile salmonids. Enhance the temporal and spatial Increase Delta outflow to provide low salinity distribution and diversity of habitats to P 7 habitat for Delta smelt, longfin smelt, and other Maintain flows and appropriate ramping rates P 11 support all life stages of fish and wildlife estuarine fishes in the Delta, Suisun Bay, and Suisun Marsh at times and locations that will minimize ✔ species P 3 dewatering of salmonid redds and prevent ✔ stranding of juvenile salmonids in side channel habitat Enhance access to fish spawning, P 12 rearing, and holding habitat by Enhance the frequency, magnitude, and eliminating barriers to migration duration of floodplain inundation to enhance ✔ P 10 primary and secondary productivity and the P 4 Improve ecosystem water quality. Dissolved growth and survival of fish ✔ oxygen, turbidity, coliform Provide water to enhance seasonal wetlands, permanent wetlands, and riparian habitat for aquatic and Remediate unscreened or poorly screened Provide flows that increase dissolved oxygen P 14 terrestrial species on State and Federal P 13 diversions to reduce entrainment of fish and lower water temperatures to support P 5 ✔ wildlife refuges and on other public ✔ anadromous fish passage and private lands Develop and implement invasive species Maintain or restore groundwater and surface management plans utilizing techniques that water interconnection to support instream Enhance habitat for native species that P 15 are supported by best available science to ✔ P 8 benefits and groundwater dependent P 16 have commercial, recreational, enhance habitat and increase the survival of ecosystems. ✔ scientific, or educational uses native species PPWD 1617 of 33 of 32 High Resiliency – Low Risk PPWD 17 of 33 Delta Provides System Wide Integration Expanded How the Project will Pacheco be Operated Reservoir San Luis Reservoir M&I and Ag Refuge water supply deliveries Modify delivery pattern to avoid Pacheco water quality Creek flows issues Water supply for Central Valley Ag and Los Angeles PPWD 18 of 32 20 of 33 The Project Performs Well in an Uncertain Future Uncertainty Scenarios Drought All Public Benefits Maintained/Increased All Public Benefits Maintained/Increased Public Project Benefits Performance Public Project Benefits Benefit Under Uncertainty Scenarios Benefit Under Drought Ecosystem Improvement - Maintained in all Ecosystem Delta Watershed uncertainty scenarios Improvement - Significantly improved (acre-feet) Pacheco Creek performance during drought (% increase in Cohort Ecosystem Score) Improvement - Maintained or improved in all Pacheco Creek uncertainty scenarios (% increase in Cohort Score) Emergency Response Maintained during drought Emergency Improved in all (acre-feet) Response uncertainty scenarios (acre-feet) PPWD 19 of 33 Broad Statewide Support Supported by: • Business • Agriculture • Disadvantaged community advocates • Labor groups • Cities/Counties • Water agencies • Elected officials • Natural resources groups PPWD 20 of 33 Successful Implementation Builds on Track Record and Financial Strength Established Operator: Santa Clara Valley Water District • 800 Employees • Manages 10 existing dams/reservoirs, constructed beginning in the 1930’s • Provides water supply, flood protection, and stewardship of streams • Serves 1.9 million people in Silicon Valley • Demonstrates excellent financial stewardship in funding its capital projects • DSOD letter regarding Pacheco: “We are pleased that SCVWD with its expertise and resources are pursuing this Enlargement Project” Pictured above: Lexington Reservoir PPWD 21 of 33 Project Partners have Technical and Financial Ability to Meet all WSIP Milestones November January May September 2021 2024 2024 2028 Draft EIS/EIR Final Commission Construction Start of Project Consideration Mobilization Operations Permits October February Late Spring 2023 2024 2025 ROD/NOD Construction Public Benefits Contract Award Begin to Accrue PPWD 22 of 33 Recap: The Project will Achieve Five Important Public Benefits Enhances Supplies Delta Provides Resolves water Supports steelhead habitat refuges emergency quality problem disadvantaged supply communities PPWD 23 of 33 Existing Pacheco Reservoir Facilities • Existing Dam/Reservoir 6,000 acre-foot reservoir 100-foot-tall earth embankment dam Concrete spillway PPWD 24 of 33 Proposed Pacheco Reservoir Facilities • Expanded Dam/Reservoir 140,000 acre-foot reservoir New 319-foot earth embankment dam Concrete spillway • Conveyance between Pacheco Conduit and expanded reservoir 1-Mile tunnel/pipeline Pump station Selective level inlet/outlet structure within reservoir •