Delta Conveyance Project (aka “The Tunnel”)

What’s the project?

Have you heard of the “Twin Tunnels,” or the “Delta Tunnels?” How about the “California Water Fix,” “WaterFix,” “Delta Conveyance Project,” or “Bay Delta Conveyance Plan (BDCP)?”

Each of these are different names for projects that all involve building at least one underground tunnel to export water from the Delta. Now the plans are for one tunnel instead of two, but that doesn’t mean the new plan is any better for the residents and ecosystems of California. Click here to learn why.

Current Information

Department of Water Resources

You can read the latest updates from the Department of Water Resources on this project at

Restore the Delta Coalition

Read the latest from the Restore the Delta Coalition at

Delta Counties Coalition

Check out the Delta Counties Coalition website at

Take Action!

Participate in a meeting

Also, the Delta Conveyance Design and Construction Authority (DCA) is conducting engineering and planning for the tunnel project for the Department of Water Resources (DWR) and meets the third Thursday of every month. The DCA is comprised of member water districts that hope to received water supplies from the tunnel. Consider tuning in to the next meeting and commenting if you can. The DCA needs to hear about the environmental problems with the project and the other better ways to meet their agencies’ water supply needs that won’t irreparably harm the Delta. More information about future meetings can be found at


April 20, 2020

The California Department of Water Resources has responded to the Delta Counties Coalition’s letter about the scoping deadline for the proposed Delta Conveyance Project in light of the COVID-19 pandemic.

Click here to read the letter.

April 17, 2020

On April 17, 2020, the Environmental Council of Sacramento (ECOS) and Habitat 2020 submitted our comments, under the California Environmental Quality Act (CEQA), on the latest iteration of the Delta Conveyance Project.

Our concerns include the following:

  • Project needs to be defined clearly
  • Appropriate alternatives must be considered for the project as a whole
  • Appropriate Alternatives must be considered for infrastructure components
  • Impact of mechanically assisted flows in the tunnels need to be analyzed
  • Analysis needs to assume that all Reusable Tunnel Material (RTM) will need to be disposed, rather than repurposed
  • Accurate transportation impacts must be provided
  • Impacts to Stone Lakes National Wildlife Refuge need to be avoided
  • The full impacts of transmission lines need to be included
  • Transmission line strikes need to be analyzed for foraging Sandhill Cranes

Click here to read our letter in full.

April 17, 2020

On April 17, 2020, the public comment period for scoping comments on the Delta Conveyance Project closed.

Click here to view a collection of comments from other organizations.

April 9, 2020

The Restore the Delta coalition has submitted a letter to the Governor requesting a Stay of Public Processes for Delta Conveyance Planning During the Novel COVID-19 Pandemic. Click here to view their letter.

April 7, 2020

The Delta Counties Coalition submitted a letter requesting a Stay of Public Processes for Delta Conveyance Planning During the Novel COVID-19 Pandemic. Below is an excerpt from their letter.

The DCC believes that disruptions caused by COVID-19 will deprive citizens, local communities, and other stakeholders the opportunity to engage with agencies on important matters, and this includes the Delta Conveyance Project. We also feel that virtual meetings are an inadequate substitute to a temporary stay of public processes around Delta conveyance. Remote meeting options are most appropriate for situations where an agency must conduct its business without delay, for instance in relation to the COVID-19 crisis and other operational necessities. Public participation via webcast or telephone cannot provide the robust public input necessary for the controversial Delta Conveyance Project. Many residents of the rural Delta and in underserved urban areas adjacent to the Delta lack reliable internet service to participate in meetings held via webcast.

Click here to read the letter in full.

Tunnel Map 2020

Click here or on the image to access a PDF version.

Tunnel Map 2016

Click here or on the image to access a PDF version.

ECOS Comments

ECOS has opposed the tunnel projects since 2015.

Click here to read comments from ECOS written in 2015.