DWP Filtration Plants May Be Built at 4 L.A. Reservoirs : Health: The $400-million plan for sites in the Santa Monica Mountains is aimed at meeting new state water-quality standards. A mediator has been hired to try to avoid the outcry from neighbors that met earlier proposals.

The Los Angeles Department of Water and Power is considering building filtration plants at four reservoirs in the Santa Monica Mountains to meet newly imposed state water-quality standards.

The plan, which would cost about $400 million, would involve the Encino Reservoir, the Lower Stone Canyon Reservoir north of Bel-Air and the Upper and Lower Hollywood Reservoirs.

DWP officials have hired a mediator to help them discuss the possibility of constructing the plants and other options with nearby residents in an attempt to avoid the outcry that greeted earlier plans to cover certain reservoirs, said Cecilia Trehuba, DWP waterworks engineer.

But some residents and state Sen. Herschel Rosenthal (D-Los Angeles) have voiced concerns about closed meetings that have been held by the DWP with a coalition of reservoir neighbors because they prohibit news coverage and limit the number of participants.

“I disapprove of the department’s covert activities, which, I understand, even require that those select few included in the discussion process must take a vow of secrecy in order to participate,” Rosenthal said in a Jan. 17 letter to Daniel Waters, general manager of the DWP.

DWP officials said all information will ultimately be presented to the public at informal community meetings and in formal hearings before a final decision is made.

“This is just one step in a long series of steps that will involve all sorts of participation, debate and review,” said Bruce Kuebler, DWP director of water quality. “I think what we have is a process to deal with the people most directly affected in a way we felt was beneficial.”

The DWP was notified in October that four of its 11 open reservoirs fall under the state Surface Water Treatment Rule, a version of a federal regulation enacted by the Environmental Protection Agency in 1989.

The rule imposes tougher health standards on reservoirs into which ground water can flow, leading to possible contamination.

No health problems have resulted from use of water at the reservoirs, Kuebler said. But to meet the state requirement, the DWP must install filtration plants at the reservoirs, abandon them, cover them or install diversion systems that would prevent ground water from flowing into them, officials said.

Some of the reservoirs are too large to cover, Trehuba said. Concrete canals used in diversion systems would ruin the natural look of the reservoirs, which many neighborhoods refer to as lakes. And the DWP cannot afford to abandon all of the reservoirs, which provide 20% of the city’s water.

DWP officials believe that building three filtration plants is the most viable solution, although no decision has been made, Trehuba said. The two Hollywood reservoirs would share one plant.

Trehuba said it is not known how big the filtration plants would be or what they might look like. DWP officials have discussed trying to disguise the facilities--perhaps as single-family houses--in order to lessen the effect they have on neighborhoods, she said.

Still, residents are concerned. “Nobody wants a huge, big industrial plant in their back yard,” said Sharon Garapedian, whose house overlooks the Encino Reservoir in a neighborhood where house prices range from $500,000 to $2 million.