map of northern california water source

Reducing Reliance on The Bay-Delta

The Sacramento-San Joaquin Bay-Delta is a network of islands and waterways at the confluence of the Sacramento and San Joaquin rivers east of San Francisco Bay. The Bay-Delta is also the hub of the State Water Project, a water storage and delivery system stretching over 700 miles from Lake Oroville in Butte County to its termination at Lake Perris in Riverside County. The State Water Project is owned by the State of California and operated by the California Department of Water Resources. Water from the Bay-Delta comes to the San Diego region via the State Water Project through the Metropolitan Water District of Southern California.

The Water Authority has a long history of supporting efforts to address the Bay-Delta’s complex environmental and water supply challenges. While water from the Bay-Delta is a critical resource for more than 25 million Californians, San Diego County is doing their part by reducing reliance on it.

Dig deeper, learn more

linkCalifornia Department of Water Resources Site download this documentBay Delta Factsheet

Water Resilience Portfolio

The Water Authority’s only source of Bay-Delta water is through its water purchases from MWD, which have decreased over the past three decades through the Water Authority and its member agencies’ long-term efforts to diversify the region’s water supply portfolio. Today, the San Diego region receives very little water from the Bay-Delta and will continue to reduce its reliance on it. Reducing pressure on the Bay-Delta aligns with state law designed to balance the environmental and water supply functions of the estuary.

State Policy
sunset over the baydelta

Delta Reform Act

The Water Authority supported the 2009 Delta Reform Act, which established the state’s co-equal goals of water supply reliability and ecosystem restoration in the Bay-Delta. The Delta Reform Act made reducing dependence on the Bay-Delta while improving regional self-sufficiency an imperative, but the Water Authority began implementing these actions many years before they were required by state law. The San Diego region has since significantly increased its water use efficiency ethic.

Executive Order N-10-19

In April 2019, Governor Gavin Newsom issued Executive Order N-10-19, directing his administration to “identify and assess a suite of complementary actions to ensure safe and resilient water supplies, flood protection and healthy waterways for the state’s communities, economy and environment.” Newsom then directed state agencies to scrap the previous administration’s plans for a twin-tunnel project in the Bay-Delta in favor of a one-tunnel system.

Board Support

In July 2019, the Water Authority’s Board of Directors unanimously supported Governor Gavin Newsom’s efforts to develop a water resilience portfolio approach that meets the needs of California’s communities, economy and environment through the 21st century. In addition to focusing on multi-benefit approaches that meet many needs at once, the portfolio advances a single-tunnel project to transfer water across the Bay-Delta. The Water Authority Board supports the single-tunnel proposal contingent on a project financing plan that treats San Diego County ratepayers fairly through the proper allocation of project costs as supply charges.

Water Authority History

A Vision Since 2013

Recognizing its importance, the Water Authority has a long history engaging in assessments of a variety of potential solutions to complex ecological and water supply issues in the Bay-Delta. Newsom’s portfolio approach is similar to a proposal the Water Authority, along with several water districts statewide, the Natural Resources Defense Council and other conservation groups proposed as a Portfolio Alternative for the Bay-Delta in 2013. That proposal included a single tunnel, new water storage south of the Delta and significant investments in local and regional water supplies.

Related Documents

Board Memos & Presentations

2021 Board Meetings

download this documentMemo: Bay-Delta Update – January 2021 download this documentPresentation: Bay-Delta Update – January 2021

2020 Board Meetings

download this documentMemo: Bay-Delta Update – April 2020 download this documentWater Authority comment letter on draft Water Resilience Portfolio – February 6, 2020

2019 Board Meetings

download this documentMemo: Bay-Delta Update – November 2019 download this documentPresentation: Bay-Delta Update – November 2019 download this documentLetter from Acting GM to Newsom re Water Resilience Portfolio – August 7, 2019

2018 Board Meetings

download this documentAdopt Revised Bay Delta Policy Principles and Position Statement on the California WaterFix Project (Action) download this documentRevised Bay Delta Policy Principles & Position Statement on California WaterFix download this documentAdopt Position Statement on the California WaterFix Project and Updated Bay-Delta Policy Principles (Action) download this documentPosition Statement on California WaterFix & Updated Bay-Delta Policy Principles download this documentStatus Report on Updating the Bay Delta Policy Principals and Developing Related Policy Statement on California WaterFix (Information) download this documentAdopt Updated Bay-Delta Policy Principles (Action) download this documentUpdated Bay-Delta Policy Principles download this documentUpdate on California WaterFix download this documentCalifornia WaterFix Update: Cost Impact download this documentUpdate on California WaterFix download this documentCalifornia WaterFix Update Presentation

2017 Board Meetings

download this documentCalifornia WaterFix Assumptions: Contractors’ Participation Level download this documentUpdate on California WaterFix and Metropolitan Water District’s Review Process (Presentation) download this documentModernizing the System California WaterFix download this documentCalifornia WaterFix Update – MWD White Paper Review: Operations and Finance / Cost Allocation download this documentCalifornia WaterFix Update – MWD White Paper Review: Physical Infrastructure download this documentUpdate on California WaterFix download this documentUpdate on California WaterFix

2015 Board Meetings

download this documentBenefits and Costs of the California WaterFix download this documentUpdate on California WaterFix and the Sunding Report download this documentUpdate on California WaterFix download this documentCalifornia Water Fix Economic Analysis download this documentStatus of Delta Stewardship Council Delta Plan

2015 Board Meetings

download this documentBay Delta Conservation Plan/California WaterFix: Potential Cost Impact to the Water Authority linkBay Delta Conservation Plan/California WaterFix: Potential Cost Impact to the Water Authority download this documentComment letter on the Bay Delta Conservation Plan/California WaterFix Partially Recirculated Draft Environmental Impact Report/ Supplemental Draft Environmental Impact Statement linkBay Delta Conservation Plan/California WaterFix download this documentReview of the Bay Delta Conservation Plan/ California WaterFix Partially Recirculated Draft Environmental Impact Report/ Supplemental Draft Environmental Impact Statement linkBay Delta Conservation Plan/California WaterFix download this documentBay-Delta Activities Update linkBay Delta Activities Update download this documentState Treasurer’s Assessment of the Affordability and Financing Considerations of the Bay Delta Conveyance Facility linkState Treasurer’s Assessment of the Affordability and Financing Considerations of the Bay Delta Conveyance Facility download this documentState Treasurer’s Assessment of the Affordability and Financing Considerations of the Bay Delta Conveyance Facility linkState Treasurer’s Assessment of the Affordability and Financing Considerations of the Bay Delta Conveyance Facility download this documentAdopt Proposed 2015-2016 Bay-Delta Workplan link2015-2016 Bay-Delta Workplan

2014 Board Meetings

download this documentDraft supplemental comment letter on the Bay Delta Conservation Plan Implementing Agreement linkBay-Delta Conservation Plan: Supplemental Draft EIR/EIS Comment Letter download this documentResolution supporting prompt completion of the Bay Delta Conservation Plan environmental review process download this documentBay Delta Conservation Plan Infrastructure Review – Response to letter from BDCP Engineering Team linkBay-Delta Conservation Plan: Draft EIR/EIS Comment Letter download this documentAuthorize the General Manager to submit a comment letter on the BDCP Draft EIR/EIS linkBay-Delta Conservation Plan: Economic and Financial Risk Assessment to the Water Authority download this documentBay-Delta Conservation Plan: Economic and Financial Risk Assessment to the Water Authority linkBay-Delta Conservation Plan: Economic and Financial Risk Assessment to the Water Authority download this documentBay-Delta Conservation Plan: Governance linkBay-Delta Conservation Plan: Governance linkBay-Delta Conservation Plan: Infrastructure Review download this documentBay-Delta Conservation Plan: Infrastructure Review linkBay-Delta Conservation Plan: Preliminary Assessment of Financing Risk Parameters download this documentBay-Delta Conservation Plan: Preliminary Assessment of Financing Risk Parameters linkBay-Delta Conservation Plan — Infrastructure Review download this documentBay-Delta Conservation Plan Supply and Demand Risk Assessment linkBay-Delta Conservation Plan Supply and Demand Risk Assessment

2013 Board Meetings

download this documentBay Delta Conservation Plan Supply and Reliability Analysis download this documentBay-Delta Conservation Plan Overview and Supply and Demand Reliability Assessment download this documentBay Delta Conservation Plan Environmental Review Process linkBay-Delta Conservation Plan (BDCP): Environmental Review Process linkPart 2: Bay-Delta Conservation Plan – Implementation Process and Portfolio Alternative Analysis download this documentBay-Delta Conservation Plan Implementation Process and Evaluation of Portfolio Alternative download this documentBay Delta Conservation Plan Estimated Export Yields linkBay-Delta Conservation Plan: Comparison of Estimated Export Yields linkBay-Delta Conservation Plan: Costs and Funding linkIs the Bay Delta Conservation Plan a Doable Deal? – Rodney T. Smith linkThe Economic Case for a No-Tunnel Bay Delta Conservation Plan – Dr. Jeffrey Michael, University of the Pacific linkEconomic Analyses Conducted on the Bay Delta Conservation Plan – David Sung, Lead Economist BDCP Program download this documentSpecial Imported Water Committee Meeting: Bay-Conservation Plan Costs, Financing, and Economic Benefits linkBay-Delta Conservation Plan: Review Update download this documentBay-Delta Historical Context and Outline of BDCP Alternatives for Water Authority Evaluation and Analysis linkBay-Delta Conservation Plan: Background and Overview linkBDCP: Water Authority Board Review Process download this documentProvide guidance on Proposed Staff Analysis for Bay-Delta Conservation Plan and Alternatives download this documentBay-Delta Quarterly Update linkOverview of Bay-Delta Issues download this documentBay-Delta Conservation Plan Update linkBay Delta Overview linkBay-Delta Conservation Plan – Paul Helliker, Department of Water Resources linkA Portfolio-Based BDCP Conceptual Alternative – Barry Nelson, NRDC linkBay-Delta Alternatives – Mike Wade, California Farm Water Coalition linkA Local Agency’s Perspective on the Need for a Business Case for the BDCP – Alameda County Water District download this documentBay-Delta Alternatives linkBay-Delta Update linkBay-Delta Portfolio Approach Alternative download this documentBay-Delta Update download this documentPortfolio Approach to Bay-Delta Conservation Plan

2012 Board Meetings

download this documentBay-Delta Update linkBay-Delta Update download this documentBay-Delta Update linkBay-Delta Update download this documentBay-Delta Quarterly Update linkBay-Delta Quarterly Update download this documentBay-Delta Update download this documentBay-Delta Quarterly Update download this documentAdopt Delta Policy Principles download this documentBay-Delta Quarterly Update linkDelta Policy Principles download this documentDraft Environmental Impact Report on Delta Plan download this documentDraft Delta Policy Principles linkDraft Delta Plan EIR linkDraft Delta Policy Principles

2011 Board Meetings

download this documentDraft Environmental Impact Report on Delta Plan linkDraft Delta Plan EIR download this documentImported Water Bay-Delta Workshop Agenda linkDelta Related State Water Board Processes download this documentBay-Delta Quarterly Update download this documentBay-Delta Presentation Agenda linkA Delta View of the Delta – Mary Nejedly Piepho, Contra Costa County Board of Supervisors linkNorth Delta Water Agency – Melinda Terry download this documentBay-Delta Activities Update linkBay-Delta Activities Update download this documentUpdate on Long-Term Bay Delta Actions