The tunnel would ensure that water resources could travel to the Bay Area from the Yosemite if another largue quake hit. Existing pipelines dates back to the 1920s.
"Only 12 companies in the world are certified to perform the job, which is estimated to cost $347 million. Digging will start next spring on the Menlo Park shoreline just south of the Dumbarton Bridge, and head eastward, with work scheduled to be completed in 2015. An additional 16 miles of pipe connecting to the tunnel on either side of the bay also will be replaced.
The job is part of a $4.5 billion renovation by the San Francisco PUC to upgrade its water system."