SAUSALITO (CBS SF) — A clogged plastic sewer pipe near a south Sausalito home caused more than 50,000 gallons of wastewater to spill into the San Francisco Bay this week.

Sausalito Public Works Department employees discovered the spill in the 300 block of Bridgeway, near Richardson Street, during a routine inspection around 7 a.m. Tuesday, said Pat Guasco, the department’s sewer systems coordinator.

A woman who lives at the home tried unsuccessfully around 8 p.m.  Monday to get a plumber to respond to a leak coming from a sewer-release valve outside her home, Guasco said.

“She thought it was her problem,” Guasco said.

Wastewater was spilling from her property across a sidewalk, into a gutter and down a storm drain that leads to the Bay about 40 feet away, Guasco said.

Public Works Department employees found that an 8-inch, 241-foot-long plastic pipe was clogged with grit and other objects that included rags and baby wipes, Guasco said.

Employees with the Sausalito-Marin City Sanitary District helped the Sausalito public works employees stop the overflow and used high-velocity flushing and vacuum pumps to clear the blockage, Guasco said.

Guasco estimated that 53,280 gallons of wastewater spilled into the Bay. The spill was reported to state water quality authorities, and water samples were taken to measure bacteria levels, Guasco said. The results are expected on Friday.

Signs warning people to stay out of the water were posted 100 feet north and south of where the sewage entered the Bay, Guasco said.

Initially, the spill was estimated to be closer to 10,000 gallons, but further calculations determined that more than 50,000 gallons had spilled, Guasco said.

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