Health advisory signs have been posted in Avila Beach after a 13,500-gallon sewage spill was reported Sunday afternoon in San Luis Obispo.
The sewage was released from a manhole because of an overflow of the mainline near 81 Broad St. about 1:30 or 2 p.m. Sunday, according to San Luis Obispo County Environmental Health Services.
The sewage went into the city’s storm drain system and into Garden Creek, which meets up with San Luis Obispo Creek and flows to the ocean in Avila Beach.
Dave Hix, San Luis Obispo’s deputy director of wastewater in the Utilities Department, said city staff is still investigating the spill but believes it happened because of heavy rains that overwhelmed the system, not a blockage or another cause.
“Looking at the rain reports we got from the weather station at Cal Poly, we think it was an intense period of rain,” Hix said. “We got about an inch and a half in two hours, and it surcharged and came out of that manhole.”
City wastewater staff who responded to the spill Sunday cleaned and sanitized the area.
Health advisory signs warning people to avoid contact with the water were posted in three locations in Avila Beach, including the children’s play area where the creek meets the ocean, and near Port San Luis, county environmental health specialist Linnea Faulkner said.
The advisory signs will be removed after after ocean water sampling finds the water meets state bacteriological standards. Samples were taken Monday, Faulkner said, with results expected Tuesday.