By Jordan Brandman
I’ll get to the part about the desalination plant in a moment, but there’s a back story that started about five million years ago. That is how long it took the Orange County Groundwater Basin to form over alternating extreme hot and glacial cold periods.
The basin is where we get 77% of our drinking water. It looks like a bowl filled with sand, rock, sediment and freshwater, with a couple of aquitards thrown in to retard water and create layers. The Orange County Water District (OCWD) manages and protects more than 300 square miles of it under north and central Orange County.
Back to the back story. Within the last 40,000 years, the Santa Ana River, which flows through the San Bernardino Mountains, through San Bernardino, Riverside and Orange Counties, deposited so many sediments that it created an opening to the Pacific Ocean.
Seawater contamination is the topmost concern and threat to our local drinking water supply. Several decades ago, we used to be able to pump freshwater near the coastline. But as the population grew and then quickly doubled, we pumped more and more groundwater out and salty Pacific Ocean water quickly moved in to take its place. The closest freshwater pumps to the coastline today are about 4.5 miles inland.
Let’s skip ahead to the 1970s. Jointly funded by the federal government and OCWD, construction began in 1971 for an advanced recycled water treatment plant and experimental Multi-Stage Flash desalter called Water Factory (WF) 21. The name was a clever description of a facility that would “make” a new source of water for the 21st century. It was the first federal desalination facility in the state of California and the largest prototype MSF distillation plant built in the U.S. at the time. WF 21 would provide product water to inject in a seawater barrier to keep Pacific Ocean saltwater from contaminating the Orange County Groundwater Basin.
The prototype advanced recycled water treatment plant, receiving source water from the Orange County Sanitation District, went into operation in 1975. At the start, Water Factory 21 was required to blend 50 percent reclaimed wastewater produced by the advanced water treatment plant with a non-waste water source. The District blended the reclaimed water with high-quality demineralized seawater produced by the MSF desalter.
The MSF desalter ran for less than a year when the Department of the Interior’s Office of Saline Water discontinued supporting the project due to an oil embargo and dramatically higher fuel prices, a faltering economy and reduced federal programs.
With committed funds and an operational wastewater treatment plant, OCWD was determined to continue WF 21 and drew its second source of water from deep wells in the basin. Water Factory 21 officially went online injecting water into the barrier in 1976. WF 21 is the first known facility in the world to use recycled water for injection into an aquifer to prevent seawater contamination. This saved considerable cost over use of imported water and provided a source of water when sufficient groundwater was unavailable to inject.
The story and WF 21 evolved. The facility became the precursor to the celebrated Groundwater Replenishment System that provides 100 million gallons of advanced purified reused water each day. About 30 million gallons are injected in the Talbert Barrier and the remainder is piped to Anaheim to be percolated in the groundwater basin, and both become part of our drinking water supply. Its final phase, which will add another 30 million gallons per day, just broke ground and is scheduled for completion in 2023.
So yes, Virginia, there really once was a desalination plant in Orange County.
This Orange County Water District article is provided by Jordan Brandman, a council member of the city of Anaheim who represents Division 9 of OCWD (ocwd.com). Contact Director Brandman at jbrandman@anaheim.net.
