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Calaveras Dam Replacement Project

Project Information
August 2011
April 2019
Cost $810 Million
Project Phase Construction
Additional Information

The information shown reflects the current forecast information published in the latest WSIP Quarterly Report.

Project Materials

Project Fact Sheet - Winter2016
Spillway Media Fact Sheet

Naturally Occurring Asbestos Information and Data

Naturally Occurring Asbestos Questions and Answers
Air Monitoring Results


Environmental Impact Report

Volume 1      • Volume 5-6
Volume 2      • Volume 5-7
Volume 3      • Volume 5-8
Volume 4      • Volume 6
Volume 5-1   • Addendum 1
Volume 5-2   • Addendum 2
Volume 5-3   • Addendum 3
Volume 5-4  
Volume 5-5  

Summary Data Reports from
Air Monitoring Events

August 2008 through August 2009
September 2009 through July 2010
August 2010 through November 2010


Need more information? Contact:

Maria Le
Phone: 925.493.4535

Betsy L. Rhodes
Phone: 415.554.3240

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Calaveras Dam construction at dusk

Project Update

Calaveras Road Advisory

From July 5, 2016 through December 31, 2017, Calaveras Road between Geary Road and Oakridge Road has been closed to vehicle, pedestrian, and bicycle traffic on weekdays for 18 months. This is due to large truck traffic on the narrow portions of Calaveras Road for dam construction.

Calaveras Road will be closed on WEEKDAYS ONLY between Geary Road and Oakridge Road – near the Santa Clara/Alameda County Line. Entrance to Sunol Regional Wilderness will be open at all times. Calaveras Road opens Saturday mornings 6 a.m. and closes Sunday evenings at 11:00 p.m.

To stay updated, please join our road closure notification mailing list by emailing  For more details on the upcoming Calaveras Road closure see the closure map and more details at

What's New at Calaveras Dam?

Construction began in 2011 to build a new earth and rock fill dam adjacent to the existing dam.  Several major components have been completed including over excavation of the secondary fault features along the pipe bench. The new spillway was completed in April 2016, including installation of the spillway bridge, and installation of all the structural concrete walls on the spillway. Dam embankment work is scheduled to begin in late 2016. As of August 2016, the project is over 80% complete. 

Project Description

The Calaveras Dam Replacement Project consists of building a new zoned earth and rock fill dam immediately downstream of the existing dam. The replacement dam will have a structural height of 220-feet high and is designed to accommodate a maximum credible earthquake on the Calaveras Fault. The dam will have a crest length of 1,210 feet, a base thickness of 1,180 feet, and crest thickness of 80 feet. The total volume of the dam will be approximately 3.5 million cubic yards. The replacement dam will restore the original reservoir capacity of 96,850 acre-feet, or 31 billion gallons of water. The storage is crucial to providing adequate water to our 2.6 million customers in the Bay Area.

Construction team standing in the newly completed dam spillway 

Team members celebrate completion of the new spillway in April 2016

Check out our time lapse video of our construction progress.

Last updated: 10/20/2016 4:33:08 PM