Existing and Proposed Seawater Desalination Plants in California

Updated: May 2016

The Pacific Institute has conducted research on desalination for more than a decade. In 2006, the Institute published Desalination, With a Grain of Salt, a comprehensive overview of the advantages and disadvantages of seawater desalination to help meet California’s water needs. In 2012, the Institute launched a series of research reports that identified the key outstanding issues for desalination in California: cost and financing; energy use and associated greenhouse gas emissions; and marine impacts. The Institute continues to examine experiences with seawater desalination around the world and to closely track desalination activity in California.

As of May 2016, there are nine active proposals for seawater desalination plants along the California coast, as well as two additional proposed plants in Baja California, Mexico that would provide water to southern California communities. This is down from an estimated 21 proposed projects in 2006 and 19 in 2012. Since 2006, only two projects have been built: a small plant in Sand City with a capacity of 300,000 gallons of water per day and a much larger 50-million-gallon per day plant in Carlsbad. Below, you can view the locations and some details about California’s existing and proposed seawater desalination facilities. We are updating these maps as new information is released, so check back often.

May 2016 Update:

  • The Doheny Ocean Desalination Project proposal was scaled back to a proposed plant capacity of 4-5 MGD, possibly expanding to 15 MGD. The South Coast Water District is now the sole project developer.
  • The City of Oceanside is no longer pursuing desalination. Although the project has not been completely abandoned, it will be at least 15 years before the city will consider adding seawater desalination to its supply mix.


Desal map 1 (2016)

Existing Seawater Desalination Plants in California, December 2015 (click to view full map)


desal map 2 (2015)

Proposed Seawater Desalination Plants in California, December 2015 (click to view full map)


Download the Series: Key Issues in Seawater Desalination in California:

dotProposed Facilities (2012) dotCost and Financing (2012) dotMarine Impacts (2013)
dotDesalination, With a Grain of Salt (Full report, 2006)  dotEnergy and Greenhouse Gas Emissions (2013)