Delta Conveyance

Delta Conveyance Aerial

The Proposed
Delta Conveyance Project 

Gov. Gavin Newsom's Delta Conveyance Project proposes to modernize the state's water infrastructure in the Sacramento-San Joaquin Delta to increase the state’s water supply reliability for 27 million Californians.

The proposed project—identified as the Bethany Reservoir alignment—features two new state-of-the-art intakes with fish screens on the Sacramento River in the north Delta and a tunnel with a maximum diversion capacity of 6,000 cubic feet per second that would move water below the Delta to the Bethany Reservoir at the start of the California Aqueduct.  A tunnel minimizes impacts to the Delta community and provides greater seismic resilience than a canal, and the location of the intakes provides resiliency to a climate-changed future, as well as extreme sea level rise. The fish screens and operational criteria are designed to meet all regulatory protections for sensitive fish species and water quality in the Delta. The proposed project would allow for the capture of water supplies during particularly wet periods. Under dry and average conditions, state project supplies would continue to move through the Bay-Delta, as they currently do.

In December 2023, the California Department of Water Resources released its final Environmental Impact Report for the Delta Conveyance Project. Read Metropolitan's statement on the release of the final EIR. 

Formed by the confluence of the Sacramento and San Joaquin rivers, the Delta serves as a critical pinch-point for the State Water Project, which on average provides about 30 percent of Southern California's water supply. This water source, along with the Colorado River and other water supplies across the West, are being threatened due to climate change and weather extremes.

The 2020-2022 drought was a powerful indicator of just how vulnerable the state project is, with historic low deliveries across the state. In Southern California, some communities could only get a fraction of the water they normally rely on, triggering forms of mandatory conservation for nearly 7 million residents. State project supplies are critically important to Metropolitan’s future reliability, along with investing in new local water sources, promoting increased conservation, building a more flexible and interconnected regional water delivery system and creating more storage that allows us to bank more water in wet years for use when it is dry. 

Metropolitan’s board and water leaders across the state will use the state's Environmental Impact Report for the Delta Conveyance Project, along with additional information to be developed in the months ahead, including a cost estimate and a project cost-benefit analysis, to determine how to best invest our resources in response to a changing climate, while also supporting the state’s coequal goal to protect, restore and enhance the Delta ecosystem. 

Metropolitan will further assess the Delta Conveyance project through its Climate Adaptation Master Plan for Water, which will guide all of our investments in infrastructure, conservation and new supplies in the years to come.  

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Canal cleaning near hinds

The Environmental Impact Report  

The environmental review process began in January 2020 when DWR released a Notice of Preparation for the Delta Conveyance Project. In December 2020, Metropolitan's board voted unanimously to fund the district's share of the environmental planning and pre-construction costs, joining other State Water Contractors. 

In July 2022, the Draft EIR was released for public comment.  This report evaluates and identifies potential environmental impacts of the proposed project and alternatives. The final report was released in December 2023 and will allow Metropolitan to conduct its own analyses and beginning in mid-2024 evaluate the potential costs and benefits of the project in support of our Board’s decision-making process.

In the months ahead, DWR will negotiate permits in compliance with the California Endangered Species Act and federal Endangered Species Act, as well as a Change in Point of Diversion from the State Water Board to ensure the new north Delta intakes would be operated to meet current laws, regulations and protections in the Delta. 

A draft Community Benefits Program Framework was included in the Draft Environmental Impact Report, signaling DWR’s commitment to ensuring benefits for the Delta community and providing an opportunity for the public to comment on the concepts included in the framework.

With certification of the Final EIR, the Community Benefits Program will officially become part of the proposed Delta Conveyance Project under consideration by Metropolitan’s board and other water leaders across the state.

California Aqueduct