California Dam to Receive Upgrades

Upgrades to the 121-year-old Crystal Spring Dam in California, US, will be carried out to improve capacity and provide a secure water supply to the San Francisco Peninsula.

The upgrade, beginning in 2011 by the San Francisco Public Utilities Commission (SFPUC), will thicken and raise the dam’s height by 9ft, raise the reservoir’s water level by 4ft and add 1.5 billion gallons of storage capacity.

The upgrades, estimated to cost between $15m and $25m, will raise the dam’s height to 92m and the reservoir’s storage to 21 billion gallons.

The work also includes widening the spillway at the top of the dam and adding a stilling basin at the foot of the dam to temper the flow before delivering it to the San Mateo Creek, according to mercurynews.com.

The project is part of the SFPUC’s ongoing $4.6bn Water System Improvement Programme and it has released a draft environmental impact report outlining the project.

Dam construction will be completed in 14 months and will involve closure of the 600ft Skyline Boulevard for rebuilding, which is expected to begin in June or July 2011.