Error Sends Nearly One Million Gallons Of Sewage Into San Francisco Bay
By Peak Johnson
Human error was the cause for the release of nearly 952,000 gallons of partially treated sewage into the San Francisco Bay late last month. An employee of the San Jose Alviso wastewater treatment plant turned the wrong valve, releasing the runoff.
Normally water from toilets, showers, and other appliances of the 1.4 million residents in the eight South Bay cities flow into the plant, according to The Mercury News.
Once at the plant, the water is treated through three levels of treatment, San Jose’s director of environmental services Kerrie Romanow said.
Romanow added that the spilled wastewater had gone through “two of the three levels” and that most of the impurities had been removed.
“It’s not raw sewage into the bay,” Romanow said. “We are thankful for that.”
The San Jose Mercury News reported that the accident did not cause any harm to public health or the environment, since most of the pollutants had already been removed before the wastewater reached the bay.
According to CBS San Francisco, the wastewater was heading to a building for its last treatment, but the filters there were being replaced when the staff member turned the valve, which was not labeled.
The error had been discovered, Romanow said, and the valve was closed 10 minutes later. Plant officials took water quality samples near the outflow pipe, and the results showed that the wastewater did not exceed state or federal health limits.
No dead fish were observed, according to The Mercury News. Romanow added that the plant discharges roughly 90 MGD of treated wastewater into the bay. What was released only represented one percent of that.
Environmentalists said they are monitoring the situation.
"It's disappointing," said Sejal Choksi-Chugh, executive director of San Francisco Baykeeper, per The Mercury News. "When you have human error, it's really unfortunate. Ten minutes is a long time, and 950,000 gallons is a lot. But luckily it was secondarily treated, so it could have been worse."
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