State of California will drain Lake Perris by 27 feet, citing earthquake fears

Monterey Herald.com

October 7, 2005

PERRIS, Calif. - State officials announced Thursday that they would go ahead with plans to lower Lake Perris by 27 feet to address concerns about seismic weakness in Perris Dam.

The decision means the Riverside County lake will lose about half its water during the peak season for boaters, water-skiers and fishermen. But authorities say the lowering is needed due to a July report that questioned whether the 2-mile earthen dam could withstand a large earthquake along the San Jacinto fault five miles to the east.

The dam holds back 42 billion gallons of water when the lake is full.

The state Department of Water Resources made the decision to drain after consulting with independent experts, the agency said in a statement.

"We are pleased that the independent panel has affirmed our interest in moving quickly to repair the dam and keep people safe," department director Lester Snow said. "While there clearly will be inconveniences as we perform the work, it is important that everyone agrees, keeping people safe is our highest order of business."

The lake has already been drained 23 feet since mid-August the lake has dropped 23 feet, a move that receded the shoreline at its two beaches by 450 feet, said Ron Krueper, superintendent at Lake Perris State Recreation Area.

In July, the department found potential safety problems with the dam that could allow major water releases. Though the department said there was no imminent threat, the state will reduce the lake level to protect downstream communities.

The lake level will remain low for several years to allow for feasibility studies, design work, and repairs, the department said.

The lake should be drained to its final level by the end of the month, said Bob Muir, a spokesman for Metropolitan Water District.

Lake Perris is about 13 miles southeast of Riverside and 65 miles east of Los Angeles.

The independent consulting board released its findings after three days of meetings with the department, which owns of the dam, the Division of Safety of Dams, which regulates California dams, and the Metropolitan Water District of Southern California, the main user of Lake Perris water.