San Onofre, local groundwater projects in desal action plan

The San Diego County Water Authority approved its 2006 Desalination Action Plan during the CWA’s October 26 board meeting, and the elements include completion of the San Onofre facility feasibility study and consideration of local desalination projects.

The elements also include continuing to seek outside funding for desalination projects and continuing to advocate for desalination on the statewide level.

“I think we need to pursue all of the options and all of the possibilities,” said Gary Arant, the general manager of the Valley Center Municipal Water District and also that district’s representative on the CWA board.

In July 2006 the CWA board opted to end pursuit of a regional desalination project in Carlsbad, although the Carlsbad Municipal Water District is continuing to explore the possibility of using the Encina power plant area for a desalination facility and the CWA likely would purchase desalinated water from a privately built facility there if the water were available at a competitive cost. The Encina plant was expected to provide 56,000 acre-feet per year beginning in 2011 and 89,000 annual acre-feet by 2030.

The CWA’s action plan is intended to meet the anticipated goal of 89,000 acre-feet of new local supplies by 2030. The San Onofre project would be in conjunction with the Metropolitan Water District of Orange County as well as Marine Corps Base Camp Pendleton, which owns the land. Federal and state grant funding account for approximately $600,000 of the total $825,000 cost of the feasibility study, and CWA staff is in the process of modifying the study scope of work in response to changes in conditions. The revised scope of work is expected to be brought before the CWA board in January 2007 for approval, and by that time concerns about how the plant will affect Southern California Edison operations of the nuclear power plant are also expected to be addressed. The San Onofre plant would provide between 50 and 100 million gallons per day of desalinated water.

“We’ve been working very closely with Camp Pendleton staff,” said Bob Yamada, the CWA’s seawater desalination program manager.

A separate element of the desalination action plan evaluates other potential regional facilities including Chula Vista sites, a border site located in the United States which would utilize the International Outfall for discharge, and a Rosarito facility located in Mexico. Regional projects are defined as those with a capacity greater than 25 million gallons per day, but smaller brackish or seawater desalination plants operated by member agencies could also help meet future demand. The City of Oceanside recently released a request for proposals for a seawater desalination pilot facility and feasibility study which would provide 5 to 10 million gallons per day at the Mission Basin Groundwater Purification Facility Site. Feedwater for that project would be obtained from extraction wells at the mouth of the San Luis Rey River. The Sweetwater Authority is studying the feasibility of an Otay River brackish groundwater desalination plant.

“This is by no means intended to be an exhaustive list,” Yamada said.

Yamada also noted the possibility of integrating local seawater desalination projects with existing or proposed groundwater desalination projects, which might allow for joint use of water conveyance or concentrate discharge facilities. “There are integration opportunities where you might be able to create some synergy,” he said. “You potentially could integrate the conveyance facilities.”

Federal and state funding reduce the costs to ratepayers. “External funding has been a significant catalyst,” Yamada said.

The CWA is a member of the United States Desalination Coalition which seeks a Federal program which would provide financial incentives for seawater and brackish water desalination projects.

Federal and state support also includes science-based and site-specific regulation. “Any new supply is going to require supportive policies from state and Federal governments,” Yamada said.

The state-level effort is focused on the State Water Resources Control Board and the California Coastal Commission, and it also includes working with the Desalination Subcommittee of the Association of California Water Agencies to ensure that ACWA’s relevant policies are properly focused.