News Feature | November 7, 2014

San Francisco Water Supply Gets Earthquake-Proofed

Sara Jerome

By Sara Jerome,

A new tunnel beneath the San Francisco Bay intended to secure the water supply in the event of an earthquakes began providing service this month.

"San Francisco water officials have turned on a new delivery system that carries water from the Hetch Hetchy reservoir to customers in San Francisco and the Peninsula. The seismic upgrade project is on time and $25 million under budget," KGO reported.

David Pine, president of the San Mateo Board of Supervisors, explained the need for the $288 million tunnel.

"We live in a very seismically dangerous area and to make this kind of investment ahead of a major disaster is unusual. Typically, we respond when there's a crisis or after a problem has occurred," he said, per the report.

The completion of the five-mile tunnel is "a big step toward securing [the area's] water supply," according to KCRA.

The launch is a milestone for the Bay since this is the first tunnel to run beneath it. It is one of 83 projects the regional water agency "has pursued over the past 12 years, part of an effort to address system vulnerabilities," the San Francisco Chronicle reported.

The tunnel is part of a larger $4.6 billion upgrade project. It "is intended to replace a pair of pipes built in 1925 and 1936 that water managers said were leaky and not going to last. It is the only tunnel under San Francisco Bay," KCRA reported.

An alternative to constructing the tunnel was considered. “Officials had two choices -- replace the aging, leaking pipes that run along the Dumbarton Bridge or bore a tunnel under the San Francisco Bay," KGO reported.

Harlan Kelly, general manager of the San Francisco Public Utilities Commission, explained why officials went with building a tunnel.

"We decided the tunnel because the tunnel was more seismically resistant and also it minimized the impact of sensitive habitat and wildlife that was on the surface," Kelly said, per the report.