The East Bay Municipal Utility District (EBMUD) is urging people to stay out of the Oakland-Alameda Estuary after 50,000 gallons of untreated sewage was released into the water Saturday, Aug. 15.

EDMUD posted about 20 signs along the estuary Saturday morning alerting people not to swim, boat or make any bodily contact with the water due to the high bacteria levels caused by the sewage. The utility district also reached out to Bay Area news outlets; San Francisco Baykeeper, a San Francisco Bay advocacy group; local rowing clubs and the California Canoe & Kayak retail shop in Jack London Square to notify them of the potential danger in the estuary.

The advisory is still in effect as of Tuesday, Aug. 18. It will remain in effect until bacteria levels in the water drop below a certain threshold, according to EBMUD senior public information representative Andrea Pook.

“The water quality is being tested every day,” said Pook. “As soon as water samples indicates it’s safe, we will notify the public. We are hoping by midweek or the end of the week it will be safe.”

Pook said EBMUD initially expected the bacteria levels to drop below the threshold in three to five days, but rain on Sunday morning delayed their expectations.

EBMUD notified the California State Water Resources Control Board (CSWRCB) of the discharge of sewage. The board is responsible for preserving quality of California’s water resources and drinking water for the protection of the environment. EBMUD has been notifying CSWRCB of the water sample results.

The discharge of sewage into the estuary was caused by equipment failure due to an unexpected power outage Friday, Aug. 14, at EBMUD’s main wastewater treatment plant in West Oakland, according to the EBMUD press release.

“The wastewater treatment received no power from PG&E between 5:10 pm and 6:50 pm. on Friday, resulting in major flooding of the pump station that transports sewage from East Bay communities via pipes to the plant for treatment,” the press release stated.

EBMUD crews worked through the night to restore the pump station at the plant. They also stored excess sewage in storage basins. However, they were unable to stop the excess flow of sewage from entering the estuary.

“Flows exceeded the storage capacity before full operations could be restored and EBMUD discharged raw sewage into the Oakland-Alameda Estuary at the foot of Alice Street. Discharges occurred between approximately 4 a.m. and 8:30 a.m. Saturday morning,” the press release stated.

EBMUD officials said they were caught off guard by the suddenness of the power outage.

“There was nothing common about this power outage,” said Pook. “We don’t often get power outages at the facility. Usually during public safety power shutoffs (PSPS) we are given notice before any outages so we can reconfigure wiring to become independent of PG&E.”

PSPS is a voluntary shutoff of electricity by the Pacific Gas & Electric (PG&E) in the interest of public safety during severe weather. PG&E conducted planned rotating power outages in El Dorado, Marin, Napa, San Mateo and Sonoma counties for several on Friday at the direction of the California Independent System Operation to relieve the power strain caused by the statewide heatwave, according to a PG&E press release. However, Alameda County was not part of the planned rotating outages.

“There were no planned rotating outages in Alameda County on Friday,” said PGE spokesman Paul Moreno. “However, power outages due occur unexpectedly. We are investigating the outage.”

Moreno said PG&E is unsure if the power outage was on their part or EBMUD. “Nonetheless we’re doing our due diligence to find the cause of what happened.”

To help mitigate the release of untreated sewage into the estuary, EBMUD also discharged disinfected and dechlorinated sewage — partially treated wastewater — from its San Antonio Creek Wet Weather Facility, according to the press release. The facility discharges at a point just west of the Jack London Aquatic Center along the estuary.

EBMUD officials are planning to have a complete report about what happened within a week. The discharge is not expected to affect water quality at Alameda Crown Beach.