SANTA CLARA, Calif. - Nearly a half-dozen Santa Clara Water and Sewer Utilities customers were without service Thursday.
A ruptured recycled waterline severed service to some customers and flooded a parking lot near Levi's Stadium.
City officials said a call came in Wednesday night about the ruptured line, but the extent of the damage wasn't visible until sunrise Thursday.
“We have a system that monitors pressure. So when the pressure decreases from a break, that goes into our control center. And then the control center will call out city staff to respond,” said Gary Welling, director of Santa Clara Water and Sewer Utilities.
City officials said fittings on two six-foot sections of pipe failed, forcing tens of thousands of gallons of recycled water into a VTA and city-owned parking lot. As a result, a sinkhole formed, measuring about 25-by-25-feet in width and four-to-six-feet in depth. Two vehicles sustained major damage. Up to six other vehicles sustained minor water damage.
Experts said the use of recycled wastewater for irrigation and commercial bathroom use is becoming more common, as a way to contain costs and preserve the environment.
“We use it for a good portion of the Guadalupe River Park in downtown San Jose,” said Jason Su, executive director of the Guadalupe River Park Conservancy. “The move to recycled water is centered around having to adapt to various conditions. And there are certain benefits we’ve found as well as certain drawbacks. And we, as the stewards of this public space, will adapt to the climate and the conditions that we’re at.”
Su said one of the drawbacks is that recycled water contains more chemicals, particularly chlorine and salt. Additives can erode the network of plastic tubes that care recycled wastewater from various cities to the plant in South San Jose.
“With any additional minerals there could be adverse impacts to what carries the water through,” he said.
City officials said the cause of the pipe’s failure is still under investigation. However, at least five additional pipe fittings similar to the one that ruptured are being checked and will be replaced if needed.
“We’re in the process valving right now, shutting off and closing valves to get water back on to those customers,” said Welling.
City officials said in a Friday update that the majority of commercial customers have access to water and that they expect all repairs to be finished sometime early next week. However, the larger problem is the sinkhole. It will take time to fill and repave the area.
Anyone who owns one of the damaged vehicles should call the City of Santa Clara at (408) 615-2003 for information on how to file a claim.