Harsh Storms Lead To Mass Sewage Spills In San Francisco Bay

After dealing with ongoing severe drought, California received an unexpected side effect after heavy storms passed over the state. Large amounts of sewage washed into the San Francisco Bay.

The East Bay Times reported that, “More than 120 sewage overflows were reported in three stormy weeks in January, and 85 sent waste into the bay or waterways leading to the bay, according to a report by the San Francisco Regional Water Quality Board, the state water pollution agency for the region.”

The West Contra Costa Sanitary District plant proved insufficient to handle the storm. The plant “spilled 9 million gallons of partially treated effluent into a marsh leading to the bay when its effluent ponds proved too small to handle the waste in a storm.”

There was more as well. The “Vallejo’s sewer system discharged about 2 million gallons into the bay. The city of San Mateo spilled 260,000 gallons.”

The East Bay Municipal Utility District (EBMUD) also released 5 million gallons of untreated sewage into the bay. Those spills were attributed to “power and equipment failures, and part to rainwater infiltrating leaky pipes and overwhelming the sewage system, officials said.”

“The storms absolutely are a time of high pollution into the bay,” Ian Wren, a staff scientist at San Francisco Baykeeper, told the East Bay Times. “I think the sewage brings the pathogens that are the most risk to people.”

EBMUD had recently announced that its drinking water reservoirs have been completely filled.

According to the East Bay Times, “San Francisco Baykeeper has participated in negotiating legal agreements requiring the city of San Jose and EBMUD to take measures to reduce the sewage overflows.”

Thomas Mumley, the regional water board’s assistant executive officer, told the East Bay Times that the impacts caused from sewage overflows are localized and near the shore, not throughout the entire bay.

Though the bay has reportedly become much cleaner since the 1970s because of pollution controls and upgrades in sewer plants, “The regional board is pressing sewage dischargers to continue reducing the overflows in ways such as improving public sewage pipes and equipment, and getting homeowners to replace leaky lateral sewage pipes that allow rain to seep into and overtax sewage systems.”

In addition to the sewage, “the bay and Delta receive big doses of chemicals, bacteria pollutants, pesticides, heavy metals, grit and debris that wash off streets.”

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