Reservoir Improvements Proposed : Water: Officials plan concrete and asphalt lining, more wells and intricate drainage system at Garvey facility.

The Metropolitan Water District of Southern California is proposing to reinforce Garvey Reservoir with concrete and asphalt lining, dig more wells, and install an intricate drainage system to prevent serious leakages such as one that flooded more than a dozen homes last year.

Monterey Park officials continue to insist that a full environmental impact report be done before any work begins on the 35-year-old reservoir but do not have any authority over the repair plans.

The reservoir was shut down and drained nearly dry in November, when divers discovered two cracks in the clay liner. Water district officials say the cracks were responsible for water bubbling from the pavement, soggy back yards, jammed doors and cracked ceilings on Fulton Avenue, downhill from the reservoir.

The MWD repair plan concludes that the cracks were caused by gradual ground shifting, probably exacerbated by the October, 1987, 5.9-magnitude Whittier Narrows earthquake. Even after it is repaired, state and water district officials say the reservoir may leak again because of its location in a seismically active area.

While in operation, the reservoir serves as a surge chamber, or relief point, that controls the pressure of water delivered to about 7 million residents in Los Angeles and Orange counties, including the cities of South El Monte, El Monte and Montebello. It does not serve Monterey Park.

The plan, submitted to city and state officials June 14, must be approved by the Division of Safety of Dams for the state Department of Water Resources. Vernon Persson, chief of the division, said his department may decide this week whether the water district’s plan is acceptable.

It calls for “armor plating” the western and southern portions of the reservoir with a slab of reinforced concrete, lining the reservoir with impervious asphalt and filling the cracks with grout.

The district is also proposing a network of gravel drains and pipes in the reservoir that would permit close monitoring of any water seepage. Any serious leak would trigger an alarm outside the reservoir. In addition, the water district plans to dig 42 wells close to the lip of the reservoir to monitor ground-water levels between the reservoir and Fulton Avenue.

Charles E. Nichols, chief engineer for the water district, said Thursday that repairs would cost an estimated $20 million to $25 million and take a year to complete.

But Monterey Park City Manager Mark Lewis doubts that the reservoir can be made safe. “We don’t want to have a solution that is not going to keep the reservoir from leaking,” he said last week.

Fulton Avenue resident Ruth Keller agreed. “‘There’s no way they can make this dam safe,” she said. “There’s a huge amount of water in there. (A serious leakage) could cause death.”

Meanwhile, the water district has received 32 claims for damages from Monterey Park residents and the city, ranging from $5,000 to $450,000. The district rejected 13, is reviewing 16 and has made offers to three people, MWD spokesman Bob Gomperz said. He said he could not give specifics of the claims.