Independent Experts Affirm DWR's Plans to Fix Perris Dam; Repair is Necessary to Keep People Safe in an Earthquake.

PERRIS, Calif. -- Following an independent expert analysis, the Department of Water Resources today announced that it will move forward with plans to repair Riverside County's Perris Dam. Seismic weakness was recently discovered under the foundation of the dam, suggesting that major damage could occur in the event of a large earthquake. DWR took action, calling for an in-depth study and recommendation by an Independent Consulting Board.

"We are pleased that the independent panel has affirmed our interest in moving quickly to repair the dam and keep people safe," said DWR Director Lester Snow. "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 independent consulting board released its findings at the conclusion of a three-day meeting with DWR, owner of the dam, the Division of Safety of Dams, that regulates the safety and integrity of all California dams, and the Metropolitan Water District of Southern California, the principal user of water from Lake Perris.

In July, DWR identified potential seismic safety problems with Perris Dam that could result in significant damage and uncontrolled water releases in the event of a major earthquake. While there is no imminent threat to public safety, the state is reducing the lake level to 27 feet blow the crest of the dam to ensure maximum protection for communities downstream. The lake level will remain at this lower level for several years while feasibility studies, design work, environmental review and repairs are completed.

DWR is required by state law to hire independent geotechnical and geology experts to evaluate the safety of all state water project dams. The board is comprised of three internationally recognized experts in geotechnical engineering and engineering geology and dam safety.

Gonzalo Castro is Principal Engineer with GEI Consultants, Inc. He received his doctorate in Soil Mechanics at Harvard University and specializes in the behavior of soils during earthquakes. N. Timothy Hall has practiced engineering geology for over 40 years, and received his doctorate in Geology from Stanford University. Faiz I. Makdisi, Principal Engineer with GEOMATRIX, has extensive experience in earthquake engineering. He received his doctorate in Geotechnical Engineering from University of California, Berkeley.

Lake Perris is located in northwestern Riverside County, approximately 13 miles southeast of the City of Riverside and 65 miles east of Los Angeles. Lake Perris is the southernmost State Water Project facility and the southern terminus for the East Branch of the California Aqueduct. It was constructed between 1970 and 1974. Lake Perris is a zoned earthfill dam, with a height of 128 feet and a two-mile crest.

The Lake Perris State Recreation Area is one of the state's most popular recreation destinations, with an average annual attendance of 1.1 million visitors. Lake Perris provides numerous water-oriented recreational activities. While the lake will remain open to boaters, fishing and swimming, the reduction in reservoir levels will impact existing facilities.

The Department of Water Resources operates and maintains the State Water Project, provides dam safety and flood control and inspection services, assists local water districts in water management and water conservation planning, and plans for future statewide water needs.