by Steve Knoblock, San Clemente City Council member

Late last summer, the South Coast Water District (SCWD) Board of Directors unanimously approved moving forward with further analysis of the proposed Doheny Desalination Project, which could potentially provide a vital drinking water resource in a time of unprecedented drought conditions.

The SCWD Board took this action after receiving exhaustive and in-depth analyses from two consultants on the water cost and potential impact on rates. What these studies found is that the cost of a five million gallons per day, or 5 MGD, desalination project would be just $2.38 per month for each home in South Coast’s service territory.

Why is this of interest to San Clemente? SCWD provides water and wastewater services primarily to residents and businesses in the City of Dana Point, and with roughly 35,000 residential and 1,000 business customers, 5 MGD is substantially more than the District could use. For this reason, the Board directed SCWD staff to seek out one or more potential agencies who could partner in this project for up to 3 MGD.

South Orange County does not sit on the Orange County groundwater basin, which is a valuable drinking water resource to those living north of the El Toro Y. As such, our region and our city are almost exclusively dependent on water purchased and imported from the Metropolitan Water District. As water allocations from northern California and the Colorado River have been reduced, the cost of this imported water has increased.

Further, this imported water is delivered to San Clemente and other communities in our region via the Joint Regional Water Supply System (JWRSS), a 35-mile large water transmission & storage system delivering MWD water from the Irvine area to the north side of Camp Pendleton. The fragility and implications of relying solely upon this infrastructure for our drinking water was highlighted earlier this year when the JWRSS Local Transmission Main, located between Calle Vista Torito and Interstate 5, failed and required a temporary bypass to continue water service to our City. At least five earthquake faults cross the length of the JWRSS – in the event of a major quake along any of those faults, this essential water delivery system could be damaged significantly, causing the interruption of service to San Clemente and south Orange County for up to six months.

In addition, in 2016 the Municipal Water District of Orange County (MWDOC) released the Orange County Water Reliability Study, which it updated in 2018. This comprehensive study of Orange County’s long-term water reliability emphasized the potential impacts of drought, earthquakes and other emergencies and found that to achieve reliability, south Orange County needs additional investments in water supply. The MWDOC Study actually ranked the Doheny Desal regional project as the top potential reliability project in the County, citing the project’s viability, cost-effectiveness, and environmental safeguards as strong project assets. 

The Doheny Ocean Desalination Project would consist of the following primary components:

•  The proposed desalination facility is located on SCWD’s existing San Juan Creek Property, on an industrial site located away from the beach.  

•  The project utilizes a water intake system consisting of subsurface slant wells that draw ocean water from offshore subsurface alluvial material (located below the ocean floor), while providing natural sand bed filtration and eliminating the entrainment and impingement of marine biota, consistent with the State Water Resource Control Board’s (SWRCB) adopted Ocean Plan Amendment.

•  A concentrate (brine) disposal system that would utilize the existing San Juan Creek Ocean Outfall sewage pipeline to return brine to the Pacific Ocean.

•  A product water storage tank, pump station and distribution system that would feed into the local water distribution system.

   •  Clean renewable energy resources, including solar panels and battery storage, would help to provide the energy for this facility, further enabling it to operate off the grid in the event of a natural disaster or other interruption of electrical service.

Another beneficial component of desalinated water is high water quality. Cities and water districts here in Orange County and across the nation have been dealing with the implications of PFAS (Per- and Polyfluoroalkyl Substances) contamination, resulting in the required remediation of most public water wells at a substantial cost.

Identifying and participating in local water resource projects is not a question of if, but which and when for cities and water districts in south Orange County. The Doheny Ocean Desalination Project represents a timely and responsible option and an excellent opportunity for San Clemente to control its destiny relative to our most precious resource, water, for the benefit of our children, grandchildren, and generations to come.