Desalination for Bay Area Regional Reliability

In our region, where drought can occur as often as once every three years, reliable water sources are vital. In 2003, five Bay Area water agencies began investigating a regional desalination project to explore the feasibility of taking the salt out of briny water to produce a potable water supply.

This regional project was envisioned to:

  • Improve supply reliability during extended droughts and natural emergencies
  • Increase operational flexibility
  • Ensure environmental protections safeguard San Francisco Bay and the Delta

The agencies, comprised of EBMUD, the Contra Costa Water District, the San Francisco Public Utilities Commission and the Santa Clara Valley Water District, were original partners in the project. The Alameda County Flood Control and Water Conservation District - Zone 7 joined in 2010.

Preliminary Studies

The agencies identified three sites (eastern Contra Costa County, Oakland near the Bay Bridge and San Francisco) that met feasibility criteria. A six-month pilot test confirmed the viability of a project in East Contra Costa County along the Delta. Costs for the preliminary technical studies, about $2.5 million, were supported by state grant funds, and the remaining costs were shared among the original four partners. The cost to plan, design and construct a regional desalination facility would depend on the use and the location of facilities. A project at the East Contra Costa location that could deliver 20 million gallons per day to Bay Area homes and businesses would cost $150 million or more, with construction occurring in phases.

Site Analysis

In early 2014, a site analysis was completed to study potential impacts on the Delta environment and confirm that the potable water produced at the East Contra Costa location could be delivered to other Bay Area regions. The partners continued public and stakeholder outreach to share the findings and seek input.

Focusing on Bay Area Regional Reliability

To cope with the severe drought California is facing, the Bay Area regional partnership shifted its efforts in 2014 and going forward. It was recognized that each agency had recently completed infrastructure projects that, when pooled together, could enhance regional water supply.

Completed projects that could be used to improve regional water reliability include:

  • The Freeport Regional Water Facility, located south of Sacramento, which includes 36 miles of pipeline, 2 pumping plants, and other works. A joint effort between the Sacramento County Water Agency (SWCA) and EBMUD, it serves as a means to convey water from the Sacramento River basin to SCWA customers as well as to the EBMUD service area.
  • Contra Costa Water District’s expanded Los Vaqueros Reservoir, located in eastern Contra Costa County. The expansion created additional water storage capacity, adding 60,000 acre-feet of storage to create a total reservoir volume of 160,000 acre-feet.

That leveraging approach also interested three other local agencies (Marin Municipal Water District, the Bay Area Water Supply and Conservation Agency, and the Alameda County Water District). The group is advancing the Bay Area Regional Reliability approach and is seeking state and federal support to fund a feasibility study to further this concept.

The benefits of a regional approach include:

  • Enhancing water supply reliability
  • Bolstering emergency preparedness
  • Addressing climate resiliency needs
  • Leveraging existing infrastructure investments
  • Facilitating the transfer of water supplies during critical periods of drought or following natural disasters

Once funding is secured, a feasibility study could be completed within a short timeframe. While Regional Desalination remains of interest, the regional reliability approach is of greater interest during the present drought.

For More Information

Alice Towey, Senior Civil Engineer for Regional Projects
Phone: 510-287-1105

Published Studies and Other Resources

The pilot test report and other available reports can be viewed on the Bay Area Regional Desalination Project website.