During a ceremony in Menlo Park on Friday launching the construction of a 5-mile long, 15-foot diameter tunnel that will cross under San Francisco Bay, crane operator Steve Cutter pulls up the "clam bucket" (photo) while digging the guide walls for the 141-foot-deep tunnel shaft.
This $347 million tunnel project is part of the $4.6 billion regional upgrade to the Hetch Hetchy water system, designed to make water delivery more secure in the event of a major disaster, such as an earthquake. The system, run by the San Francisco Public Utilities Commission, delivers water to millions of customers on the Peninsula, the South Bay and in San Francisco.
The massive rebuilding project is expected to be completed by 2015, SFPUC officials said.
This ceremony took place at 5000 University Ave. in Menlo Park, near the approach to the Dumbarton Bridge.
For more information on the project, go to sfwater.org/baytunnel.