Investigators have discovered the cause of a large sewage spill that prompted the closure of a stretch of Pacific Beach from Crystal Pier to just south of Tourmaline Beach last week.
Someone had dumped a "significant amount" of pea-sized gravel into a manhole near the beach on Missouri Street, a city spokesperson said, which caused sewage to backflow into a storm drain system.
"The diversion structure is not designed to convey wastewater to the storm drain, but stormwater to the sewer," the spokesperson said.
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The city of San Diego's Public Utilities Department is investigating the vandalism. The city did not provide more information on where the investigation stands or if anyone could face consequences for the dumping. San Diego police is not involved.
It was unclear when exactly sewage began seeping into the Pacific Ocean but the County's Department of Environmental Health and Quality confirmed about 25,000 gallons of waste poured into the sea near Missouri Street last week.
The spill prompted the agency to issue Friday a water contact closure for the beach from Loring Street to Hornblend Street. The closure was lifted on Saturday.