CBS 5 Investigates With Anna Werner

SF Muni Blamed For Leaking Underground Water Pipes

CBS 5 Investigates

SAN FRANCISCO (CBS 5) ― Call it the mystery on San Francisco's 15th Avenue.

"I open up over here and water come out a lot," said resident Kevin Luu. "We noticed water coming through. it was a mystery," added his neighbor, Gordon Jong.

Water pipes, up and down the street, are leaking: "Probably 7 times," estimated Jong. And "5 times for this last 4 years," said another neighbor, Alex Doliner.

Doliner even took pictures of the copper water pipes under his driveway that sprung a major leak. "So you literally saw the water coming down the driveway and going down the street?," CBS 5 Investigates asked. "Not 'literally', a lot!" responded Doliner.

Since many of the residents said their water bills are skyrocketing, CBS 5 asked the San Francisco Water Department to take a look. At our request, they ran tests and analyzed complaints.

"The amount of customer service leaks is unusually high here," Water Department chief Kevin Barry told us.

How many leaks? Nearly two dozen in a single block. And some huge water bills. "About $326 dollars," said Luu.

But residents aren't blaming the water department. They suspect something else on their block: The light rail line, running right down the middle of the street. Light rail lines, corroding underground pipes? Who ever heard of that? And is it even possible? The answer? Yes. It's something called 'stray current'.

Those light rail systems run on electricity or current which comes into the train through lines at the top beginning at a transformer station far away. The current then continues on and goes back to the station through the rails in the ground. But sometimes, some of that current strays from those rails. When it does, it is called 'stray' current, that can wind up in nearby metal pipes and corrode them. Often the result is this: clear holes in pipes, eaten away from the outside.

So could that be the answer to the mystery on 15th Avenue? CBS5 interviewed two experts who agree the cause could be Muni's light rail system.

Expert Laszlo Forgo, who also works on corrosion issues for PGE, told CBS 5: "I think it is possible that the large number of leaks on these water service pipes are generated by stray current corrosion."

"So, you're thinking that it could come from the light rail system," CBS 5 Investigates asked him. "I think it is," he responded.

But not so says Muni spokeswoman Maggie Lynch.

"Well we've certainly had rail in the city for over 100 years, and it's never come up," she said.

Yet CBS 5 found problems with stray current and pipe corrosion reported all over the country: Houston, Salt Lake, Denver and Seattle.

"I'm not sure what the deal is in Seattle, but here, we've never had an instance of it and this is really the first we've heard of it." Lynch told CBS 5.

First Muni has heard of it? Then, why did CBS 5 Investigates find a document from her own agency, related to Muni's new 3rd street light rail, project that discusses "stray current problems in the Muni rails."

And what did Lynch say about that? CBS 5 Investigates never got the chance to ask her.

"You know what, ok – I think we're finished," she told us, and walked out of the interview, adding, "I don't know whether you think you're '60 Minutes' or what."

Dolinar thinks Muni just doesn't want to hear it.

"Muni don't want to help," he said. And why, we asked? "Because they don't want to spend money for this," Dolinar surmises.

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