A failed San Francisco Public Utilities Commission pipe has been pouring millions of gallons of fresh water in the Bay and will continue to do so while the water provider finishes a multi-million system upgrade slated to be completed this year.
The pipe, located just south of the Dumbarton Bridge just offshore from East Palo Alto, has been leaking an average of 25 gallons of fresh water per minute for the last four to five years. Based on the SFPUC’s estimates, between nearly 52.5 million gallons and 65.7 million gallons of fresh water have been wasted since it first became aware of the leak.
Although the pipe has been leaking for years, it will soon be abandoned when the SFPUC completes its Bay Tunnel Project as part of a total $4.6 billion regional system upgrade, said David Briggs, local and regional water manager for the SFPUC.
The SFPUC determined fixing the leak would cost millions of dollars and could be hazardous to workers who would need to be barged underneath the pipe that’s approximately 15 to 20 feet above the water near a wooden pier, Briggs said.
“We’ve done everything we feasibly could under the circumstances. … We’re effectuating a repair as fast as we possibly can,” Briggs said. “We’ve put all of our energy into that [Bay Tunnel Project] and it should come online in early October. In short, conducting that repair on the end of a wooden pier would not be simple, safe or cheap. And the overall leakage, I know it sounds bad, but in a regional water system that conveys 250 million gallons a day, this amount of water loss, although it’s noticeable for some, it’s extremely small.”
The entire SFPUC regional water transmission system uses about 260 miles of pipes to carry approximately 250 million gallons of water each day from the Hetch Hetchy Reservoir to Bay Area customers, Briggs said.
The leak is coming from at least one of two approximately 60-inch-diameter pipes that span from Fremont to Redwood City and carry about 100 million gallons of water each day, Briggs said.
The pipes were built in the 1920s or 1930s and an expansion joint that’s affected by the climate is causing the leak, Briggs said.
Briggs said the SFPUC checks the leak and tightens the bolts regularly and, although these pipes are a major arteries in the system, replacing them with the tunnel will help prevent future leaks.
Some are surprised and frustrated that while the government and providers push for conservation during the severe drought, a powerful utility isn’t doing all it can to save the limited resource.
“I do so much to try and conserve water, and my family does too. To see that the water district is itself wasting so much water, that isn’t being used, that was kind of disheartening,” said Robert Snedden, a Mountain View resident who noticed the leak while on a hike along the Bay Trail with his father Scott and contacted the SFPUC. “I know it’s a drought and the government puts restrictions on people using water … it’s kind of weird to see the [SFPUC] saying every drop counts but not living up to their motto.”
Scott Snedden said the SFPUC has been complacent with the waste and wonders why over a four-year period the large utility couldn’t have at least found a temporary fix.
“We were surprised that this leak couldn’t be patched. … Isn’t that their business? They have elevated pipelines going over the Bay; you’d think they’d have equipment to maintain it. But I guess they just made the decision that somehow it’s more cost effective to let it leak than to fix it,” Scott Snedden said. “It’s all about the money, otherwise they’d be fixing it. So I guess the money’s more important than the conservation.”
The SFPUC has undertaken a multi-billion dollar capital improvement project and the leaking pipes will be abandoned after the Bay Tunnel Project is completed in the coming months, Briggs said.
“We’re aware that in the drought situation that we’re in, of course every drop matters and we’re doing everything that we can on a variety of fronts to save water and reduce demand through conservation,” Briggs said.
With the new distribution system as a long-term solution, the SFPUC determined repairing the leak wasn’t worth the cost or risk, said SFPUC spokeswoman Amy Sinclair.
“Because these pipes are going to be completely taken out of service, we’ve made that decision not to make these repairs. We also have an exemption from the State Water Resources Board for an exemption for this leak,” Sinclair said.
The SFPUC recognized its infrastructure was nearing the end of its lifetime and no longer seismically safe, Sinclair said. In 2002, San Francisco voters passed Proposition A, which approved the $4.6 billion bond to fund upgrades that include the $288 million five-mile-long Bay Tunnel Project.
The 15-foot-diameter tunnel was dug at depths up to 100 feet and will house a 9-foot-diameter steel pipeline that will run under the Bay from Newark to East Palo Alto, according to the SFPUC. After exiting the Bay, it becomes a normal pipeline buried about 5 feet underground and terminates near northwestern Redwood City. The project assists in creating a seismically safe backbone for the conveyance system that stretches from Sunol Valley up to San Francisco, Briggs said.
The project started in 2010 and will be finished earlier than expected.
Still, as the current pipe will remain in use and continue to leak until the Bay Tunnel Project is complete, another million gallons of water could be wasted over the next month alone.
Last week, the SFPUC released its mid-year supply update announcing the Hetch Hetchy storage system stands at just 64.5 percent of its 117 billion capacity. It also announced conservation efforts were at a slow start and the SFPUC had only saved 17 percent of its 8 billion gallon year-end savings goal.
Having consumers boost conservation efforts and completing the new system upgrades is what will effectively help the Bay Area manage the drought in the long run, Sinclair said.
“We are obviously very conscious of the drought situation. But when you look at the amount of water going through our system, it’s a very small amount,” Sinclair said. “This leak is going to be short term. [The Bay Tunnel Project] is long term. ... But what people can do is really long term and that’s developing (conservation) habits.”
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