Deadlines for Filtration Plants OKd : Water: The construction, estimated to cost $500 million, will help Los Angeles supplies meet state purity standards.

A series of deadlines were set Tuesday requiring Los Angeles water officials to build three water filtration facilities to serve four reservoirs at a cost of $500 million.

The plants will help city water supplies meet state standards for purity, but their construction could cost Department of Water and Power customers an average of $3.20 per month for the next 10 years, starting next July.

Under an agreement signed by DWP commissioners and the state Department of Health Services on Tuesday, DWP is required to purify drinking water exposed to the elements in Encino, Hollywood and Stone Canyon reservoirs.

“This basically formalizes something we’ve been working on for quite some time,” said Bruce Kuebler, DWP director of water quality. “It’s a major undertaking.”

Water officials missed a June 29 deadline to comply with the state’s Surface Water Treatment Rule, which deals with bacteria, viruses and other contaminants that might enter the reservoirs in storm runoff. As a result, DWP was required to inform customers through public notices that water in the open reservoirs no longer meets state standards and poses risks of waterborne disease.

The utility has since applied to the health department for an extension of the deadline. A public hearing is set Aug. 4.

Kuebler said the agreement, which contains a number of interim requirements over the next 10 years, is an important step in ensuring the quality of water at the reservoirs.

“It will provide a reliably better quality of water to our customers,” he said.

Under the agreement, work on a filtration plant at Stone Canyon will be completed in 1998, Upper and Lower Hollywood Reservoirs by 2001, and Encino Reservoir by January, 2003.

Kuebler said DWP officials hope to have a financing plan for the project, which could raise the average customer’s water bill $3.20 per month for the next 10 years, within a year.

A state health official praised the agreement, saying it shows that the city is serious about complying with state standards.

“This is not the normal way things are done,” said Gary Yamamoto, acting regional engineer for the health department’s office of drinking water. “A lot of cities are going to have to be forced into compliance on this. This agreement signifies that the city really intends to comply.”