San Francisco has taken a big step toward securing its water supply with the completion of a $288 million tunnel below San Francisco Bay.
The San Francisco Chronicle reports that water from Hetch Hetchy Reservoir in Yosemite National Park was to begin flowing through the tunnel this week. Hetch Hetchy is a key part of a water system that serves more than 2 million customers in the San Francisco Bay Area.
The tunnel 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.
It is part of a $4.6 billion project approved by voters that seeks to upgrade the Hetch Hetchy water system's aging pipelines, tunnels and dams in case of an earthquake.
