Oceanside allocates $4.7 million more to Pure Water project

Oceanside has approved spending an additional $4.7 million on its Pure Water project, which injects purified wastewater into the Mission Groundwater Basin in the San Luis Rey Valley for removal later to blend with the city’s tap water.

That brings the total allocated so far to $8 million for a contract initiated in 2020 with the consulting firm Trussell Technologies covering “design and integration services to optimize both maintenance and operation” though June 30, 2029, according to a city staff report.

“This is a major accomplishment and an important investment that will bring long-lasting benefits to the Oceanside community,” said Mabel Uyeda, the city’s water engineering manager.

“We are working to automate processes, continue plant improvements and operations, and build staff knowledge and technical expertise,” Uyeda said, at the Oceanside City Council’s Aug. 20 meeting, where the contract amendment was unanimously approved.

“This is about strengthening what we have already built and ensuring the system delivers for decades to come,” she said. “This is about making the plant operate better and smarter.”

The city began its Pure Water project in 2016, construction started in 2020 and the first purified water was produced and injected into the ground in 2022. The purified water is withdrawn from wells and mixed with water from other sources to be distributed by the city’s water department.

The facilities are designed to place up to 3 million gallons of water per day into the groundwater, or enough to supply about 20% of the city’s daily needs. Plans call for a phased expansion of the system to eventually produce more than 30% of the city’s supply.

The largest share of water consumed throughout San Diego County is imported by aqueducts from outside the county. Most is from the Colorado River, but a smaller amount is from the Sacramento-San Joaquin Bay Delta in Northern California. None of California’s water comes from the Pacific Northwest.

In all, Oceanside has spent more than $70 million on the Pure Water project, with much of the money from federal and state grants and loans. The recycling program is intended to provide a dependable local source and reduce the city’s reliance on costly imported water.

Last year, the U.S. Bureau of Reclamation awarded Oceanside $15 million to further several programs that reduce the city’s reliance on imported water.

Almost half of the grant money, or $7.1 million, was for the Pure Water Oceanside project. The rest of the money was for additional equipment at the city’s Mission Basin Groundwater Purification Facility and for other water recycling facilities.

Oceanside has been extracting brackish groundwater from the Mission Basin and filtering it using the reverse osmosis process to supplement the city’s potable water supply since 1992.

However, the supply and quality of the groundwater has diminished in recent years and is threatened by the intrusion of saltwater from the nearby Pacific Ocean. The Pure Water program is intended to help restore and safeguard groundwater levels.

Camp Pendleton, the city of San Diego, and several other water districts in San Diego County have potable reuse systems like Oceanside’s Pure Water program.

The Orange County Water District has been using a groundwater replenishment system since 2008 to meet the daily needs of nearly 850,000 residents.