Department of Water Resources

1416 Ninth Street
Sacramento, CA 95814

Mailing Address:
P. O. Box 942836
Sacramento, CA 94236

 

Perris Dam Project

In 2005, the Department of Water Resources (DWR) identified potential seismic safety risks in the foundation of Perris Dam, located in northeastern Riverside County, 11 miles southeast of Riverside and 60 miles southeast of downtown Los Angeles. While there was no imminent threat to life or property, in the interest of ensuring public safety, the state lowered the water level of Lake Perris to conduct the EIR process and complete repairs.

DWR certified and adopted the Perris Dam Remediation Program final Environmental Impact Report (FEIR) on November 18, 2011. The Notice of Determination was filed with the State Clearinghouse and the Riverside County Clerk on November 23, 2011.

An electronic copy of the FEIR may be viewed and downloaded at the link in the left hand column of this page.

Hard copies of the document may be viewed and photocopied at:

Department of Water Resources
Division of Operations and Maintenance
Environmental Assessment Branch
Kim Flaherty
1416 Ninth St., Room 620
Sacramento, CA 95814
(916) 653-3943

Department of Water Resources
Division of Integrated Regional Water Management
Southern Region
Mary Miller Guerin
770 Fairmont Ave., Suite 102
Glendale, CA 91203
(818) 500-1645

The Perris Dam Remediation Program, the project proposed to implement repairs to the dam, was analyzed in a draft EIR (DEIR), released in January 2010. The DEIR included three separate project components: (1) Perris Dam remediation, (2) outlet tower replacement, and (3) emergency outlet extension. The proposed repair plan includes upgrading the dam by strengthening roughly 700,000 cubic yards of the foundation material with cement-deep-soil-mixing methods and reinforcing it with a stability berm placed on top of the improved foundation. This would allow the lake to return to its previous maximum operating pool elevation after construction.

From January 2010 through April 2010 DWR solicited public input through a series of meeting. Following review of the public comments on the DEIR and preparation and review of the Final EIR (FEIR), DWR staff recommended approval of the first two of the three project components.

The emergency outlet extension component is being deferred in order to evaluate an additional alternative that will address recommendations and comments received from local governments and agencies during the DEIR public comment period. A separate CEQA document for the emergency outlet extension will be prepared as necessary within the next year.

We anticipate completion of the dam remediation design by the end of 2013, and construction to begin in 2014. Completion of the dam remediation construction is expected at the end of 2015.

Lake Perris is located in northern Riverside County, and is the southernmost State Water Project facility and the southern terminus of the East Branch of the California Aqueduct. 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.

If you have comments, questions, or would like to receive current updates regarding the Perris Dam Remediation Project, please contact DWR at perrisdam@water.ca.gov.

This website was last updated on 12-01-2011.