Local Water, Local Solutions
South Coast Water District’s Groundwater Recovery Facility

South Coast Water District added the first drops of local water to its distribution system in Dec. 2007 from its new Groundwater Recovery Facility in Dana Point. Approximately 10% of the District’s potable water now comes from a local source, the San Juan Groundwater Basin, rather than Northern California or the Colorado River.

“We built this facility to produce a sustainable, local supply of potable water in the face of decreasing imported supplies,” said Mike Dunbar, PE, General Manager. “Adding 10% of local water to our supply now and another 10% in a few years with the addition of a second well is significant to a District that has been wholly dependent on imported water.”

The District provides water to Dana Point, South Laguna and areas of San Clemente. Annual demand is approximately 7,500 acre-feet of water or 2,500 million gallons. “By tapping into this local source, we reduce reliance on imported supplies, which are decreasing due to drought, climate change, court decisions and changes in government policy,” said Dunbar.

Initially, the facility will yield 800 acre-feet or 260 million gallons of potable water a year (712,000 gallons a day). Ultimately, the District will add a second well to produce 1,500 acre-feet or 489 million gallons of water a year (1.3 million gallons a day).

To ensure future water reliability, the District will continue to diversify its potable supply, provide recycled water, promote water conservation and expand water storage. “There is no one solution to water reliability, no ‘silver bullet.’ It requires a mix of solutions, and developing local supplies is a critical component of that mix,” said Dunbar.

click on graphic for close-up

RO--Heart of the Facility. Located on two acres of District property next to San Juan Creek, the groundwater recovery facility uses state-of-the-art reverse osmosis technology. The heart of the facility is a 22-foot-tall, 2,650-square-foot plant housing the RO system. The facility recovery rate is approximately 76% and recovery process consists of:

1. Groundwater extraction (128-foot-deep well, 800 gallons per minute)
2. RO pre-treatment (chemical, filtration)
3. RO treatment to remove impurities and total dissolved solids (300 HP pump, 300 psi; 27 pressure vessels, seven RO membranes per vessel; 18 vessels currently in use)
4. Iron/manganese removal from the groundwater
5. Removal of excess CO2 and disinfection
6. Continuation of step 5
7. Temporary storage of finished water in a 20,000-gallon tank prior to distribution
8. Backflow prevention ( About 267,000 gallons a day of water waste e.g., brine, backwash, passes through the Air Gap before discharge to a South Orange County Wastewater Authority outfall.)

South Coast Water District and its predecessor agency, the Capistrano Beach Water District, had contemplated building a groundwater recovery facility for more than a decade. Construction began in 2005, finished in 2007 and cost $5.8 million. Funding came from $8.8 million in bonds that the former district sold in 1998. To support local water development, the Metropolitan Water District of Southern CA will give the District $250 per acre-foot of water produced, approximately $5 million in subsidies over 20 years. Operating costs for the facility are projected at $717,000 per year.

To learn more, click here to download an informative brochure. (pdf file; 800kb)