SAN FRANCISCO(CBS SF) – The recent storms in the Bay Area caused at least two sewage systems to overflow and spill into the San Francisco Bay.

Some 900 gallons of waste water spilled from a manhole cover in Sonoma County on Monday. Deb Self, executive director of the environmental non-profit group San Francisco Baykeeper, said this wasn’t the only reported sewage spill.

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KCBS’ Anna Duckworth Reports:

“East Bay Municipal Utility District’s wet weather facilities did have to discharge a fair amount during the last set of storms,” said Self. “That’s to be expected whenever we have a big rain storm. But it does mean that partially treated sewage is making its way into the Bay.”

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During last year’s rainy season, about a quarter billion gallons of sewage spilled into San Francisco Bay, mostly because the rainwater seeps into and overwhelms damaged pipes.

Because spills violate the Clean Water Act, in recent years, Baykeeper has settled 10 lawsuits against 20 cities.

“We research the numbers of spills that each city and sanitary district have,” said Self. “So we’re looking for the worst performing systems that have a systemic problem with deferred maintenance.”

Self said she expects improvements mandated by the settlements will mean fewer sewage spills into San Francisco Bay by 2019.

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