MWD Hopes to Put Lid on Algae Growth at Reservoir

Times Staff Writer

What's it all about? Algae.

That and other water quality problems are creating difficulty at the the Metropolitan Water District's Palos Verdes Reservoir in Rolling Hills Estates.

Chemicals that occur naturally in water brought from Northern California, together with bird droppings, have produced bacteria and algae in the reservoir, which supplies several communities.

Water in the reservoir must be kept low and in constant circulation to prevent the buildup, said district spokesman Bob Gomperz. "And we need to super-chlorinate it, which causes some people to complain about the taste."

Built in 1939 to hold 358 million gallons, the reservoir--at the intersection of Palos Verdes drives North and East--has been operating at only a quarter of its capacity for several years to minimize stagnant conditions and algae growth, according to the district, which is a water supplier in six Southern California counties.

Rubber-Like Cover

Now, Gomperz said, the water district is proposing to get on top of the problem by spending $10 million to put a floating gray, rubber-like covering over the reservoir. The covering would eliminate sunlight, which causes algae to reproduce, and would keep out airborne contaminants. It also would prevent disinfectants in the water from escaping into the air.

"There is no health hazard in drinking this water, which is constantly monitored," Gomperz said. "The need is to improve the quality and to give us an emergency supply."

Filled to capacity, the reservoir could provide 66,000 people with water for a month in case an earthquake or other emergency cut off regular water supplies.

Three years ago, the water district proposed covering the reservoir, only to encounter protests from hillside residents who overlook the 30-acre site.

Lose Lake View

"They were afraid they would lose their lake view," Gomperz said. "But it's not much of a lake view, just a concrete apron with some water at the bottom."

Hoping for a better reception this time, the district will hold a community meeting on Tuesday at 6:30 p.m. at reservoir headquarters, 2300 Palos Verdes Drive North. About 200 families with reservoir views were sent invitations last week.

Gomperz said engineers and water quality experts will explain the water problems and answer questions. A presentation also will be made on Tuesday to the Rolling Hills Estates City Council.

Some residents already are having their say, pro and con.

"A cover would be an eyesore," said John Trask. "The reservoir would be much prettier if it were filled up, but it looks better now than if they had a big cover over it."

No Objection

Joyce Rabinov said she likes looking at the water but would not object to the covering if it would improve the water supply.

"I don't see a problem one way or the other," said Rodney Norris. "The reservoir is a landmark but we've grown practically to ignore it."

Gomperz said that even if there is substantial opposition, the water district board could order the reservoir covered: "There is a need and it serves thousands of other families besides those who overlook it."

It would take about three months to cover the reservoir. During that time the reservoir would be out of service and a bypass system would be used.

The district last year covered Garvey Reservoir in Monterey Park and substantially eliminated a bacteria problem, Gomperz said, adding that no homes overlook that reservoir.

Sufficient Water

Water from the Palos Verdes Reservoir is purchased by the Los Angeles Department of Water and Power and the West Basin Municipal Water District and is distributed in Rolling Hills Estates, Rolling Hills, Rancho Palos Verdes, Palos Verdes Estates, San Pedro, Lomita, Harbor City and portions of Wilmington and Torrance. Despite the low level of the reservoir, Gomperz said it has enough to supply customers.

The reservoir operated close to capacity until 1973, the year after the district began importing Northern California water, Gomperz said. He said that that water has high levels of phosphates and nitrates, which stimulate algae growth.

Passing sea gulls, ducks and other birds also have made their contributions, he said. "They drop fish parts taken from the ocean, and feces, and it all harbors bacteria colonies."

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