Oceanside Makes Plans to Desalinate Water : Utilities: City hopes the plant can supply 6% of its needs by 1993 by treating well water, thus lessening reliance on the MWD.

For 20 years, Oceanside has depended on the mammoth Metropolitan Water District of Southern California for its water. But now the city has become the first in San Diego County seeking to desalinate its own well water.

Eventually, Oceanside officials hope, desalinating brackish well water could meet half the city’s water demand, plus give the community of 133,000 people something else it critically needs: a source of water for emergencies.

The city has preliminarily approved a $4.3-million, 2-million-gallon-a-day, reverse-osmosis desalination project that initially would supply 6% of the city’s water needs when the plant starts up in early 1993.

“It’s a start for us to become more water-independent,” city spokesman Larry Bauman said Wednesday. “It’s a small start, but it’s a significant one for us.”

The MWD’s board has already approved the Oceanside project, though a contract must still be signed. Similar projects have been approved for Tustin and Irvine in Orange County, and other communities have expressed interest.

In San Diego County, water districts serving Chula Vista, National City and Otay Mesa are in the early stages of exploring such desalination projects, according to Dana Friehauf, a water resources specialist with the San Diego County Water Authority.

“I think it’s fantastic what they’re doing. It makes common sense to reclaim water,” Friehauf said. “This brackish ground water is sort of an untapped resource.”

Years ago, Oceanside took its water from the San Luis Rey River basin, but the well water was poor-tasting and too salty. So 20 years ago--when water was cheap and plentiful--the city began getting its water from the MWD.

In recent times, the drought has raised the cost and limited the availability of water, sparking greater interest in finding ways to develop local water sources.

Barry Martin, director of water utilities for Oceanside, said money to build the desalination project has been set aside from water rates paid by city residents.

Currently, the city pays $323 for each acre-foot of water it buys. An acre-foot is about 326,000 gallons, the amount that two families use a year. The water comes from the MWD, but the county water authority acts as the middleman for San Diego County’s communities.

Under a well-water desalinating project, the cost of water would increase to $513 per acre-foot, but the hike wouldn’t be passed on to consumers through their water bills, according to Martin. Rather, the MWD would subsidize the higher cost because that’s cheaper than bringing in more water from outside Southern California.

Ground water desalinating projects “are part of Metropolitan’s continuing efforts to help develop local water supplies,” MWD General Manager Carl Boronkay said in a statement.

“By doing so, we decrease the ever-growing demand for the limited supplies that Metropolitan imports from Northern California and the Colorado River,” he said.

If anything, Martin believes the desalinating project would help avoid having to rely on the fluctuating price of water. “We’re hoping to at least stabilize water rates in the future,” he said.

He also believes that although the project will start small, it will be expanded so that “within the next five or 10 years, we’ll have probably half our supplies met from the basin.”

Oceanside is also eager to maintain a local supply of emergency water in case the state’s water-delivery system is disrupted. Currently, if any aqueducts were broken, such as by an earthquake, “we’d have a two-hour water supply to some areas of the city,” Martin said.

Nearly 10 years ago, Oceanside proposed building a reservoir in a bucolic canyon to store emergency water, but public opposition killed the plan.

The desalination project, which involves digging two wells, would be built at the abandoned San Luis Rey Wastewater Treatment Plant off Mission Avenue at Heritage Street.

Treatment would consist of an aerator, filters, membranes and chemicals. The reverse-osmosis system would provide the final stage of treatment.