Oceanside, located on the northern coast of San Diego County, has significantly reduced its reliance on imported water through its pioneering purified recycled water program. Prior to the project, the city imported 89% of its consumed water. Today, that figure stands at approximately 67% and is projected to drop to 44% upon completion of the facility’s second phase.
Backed by a $71 million investment, the city treats its own wastewater to produce clean drinking water and even welcomed a delegation from Baja California, which toured the facility in June.
Known as Pure Water Oceanside, the program is the first of its kind in the county. It utilizes treated water from the San Luis Rey Water Recovery Facility, subjecting it to ultrafiltration, reverse osmosis, and advanced ultraviolet oxidation. The purified water is then injected into the Mission Basin aquifer, before being extracted for final treatment and distribution as clean drinking water. This process is classified as indirect potable reuse.
The facility currently operates at a capacity of 4.5 million gallons per day, with plans underway to expand output to 6 million gallons. Although initial reports in 2022 estimated capacity at 3 million gallons, recent facility updates reflect the expanded 4.5-million-gallon benchmark.
Oceanside also manages the “La Salina” plant, built in 1949 and recognized as the city’s oldest wastewater treatment facility, which provides secondary treatment prior to ocean discharge. Meanwhile, the San Luis Rey facility continues to produce recycled water for urban landscaping, parks, and golf courses, and it’s the primary source for the Pure Water initiative.
On June 23, the Institute of the Americas hosted an educational tour of Oceanside for municipal representatives from Tijuana and Tecate. The visit provided the Baja California delegation with strategic insights into how Oceanside developed a resilient, localized water source amid ongoing regional challenges, including prolonged drought and declining reliability from the Colorado River.
