Murky water in Aquatic Park in Berkeley on Sept. 11, 2019. Photo: John Dye

The water in West Berkeley’s Aquatic Park is currently unsafe for any human contact, the city said Friday evening, following substantial increases in bacteria there, new lab tests show.

Numbers for the fecal bacteria E. coli and the intestinal bacteria enterococci were way above normal standards this week, the city told Berkeleyside.

The city began testing the water in the lagoon weekly for E. coli and other fecal bacteria following a bacteria spike in August, as Berkeleyside previously reported. Formerly, the city tested the water at Aquatic Park monthly on a seasonal basis.

This week, for the first time, the city began checking the water for enterococci levels after contracting with a private lab in Livermore to run those tests, said city spokesman Matthai Chakko. Experts had previously told Berkeleyside that recreational marine water safety standards had shifted in recent years toward a focus on that type of bacteria rather than E. coli.

Tests from water sampled Tuesday at Aquatic Park for enterococci found extremely elevated levels of that bacteria: 370 bacteria per 100 milliliters at the north end of the lagoon; 650 in the middle; and 520 at the south end. For enterococci, any value over 30 is considered high in marine recreational water, according to the State Water Resources Control Board. (One caveat is that, statistically, water experts generally review mean results over at least six weeks before drawing substantial conclusions.)

The city also took enterococci samples from the lagoon Friday and was driving them out to Livermore for testing, Chakko said. As of publication time, staff were also posting bilingual signs around the park in English and Spanish to warn of health risks related to water contact.

“Recent testing shows elevated levels of bacteria,” the signs read. “Water contact may cause illness. Shower and towel dry after contact.”

E. coli levels were also high at Aquatic Park this week, Chakko said, coming in at 450 in the middle of the park on a scale that puts safe levels at 100. The test results for the north and south ends of the park were not immediately available pending questions the city needs to clarify with the lab about them, said Chakko.

Friday’s numbers followed two weeks of E. coli levels that were within safe standards, according to the city.

It’s very possible that rains in Berkeley earlier this week could have washed fecal matter into the lagoon, elevating bacteria numbers in the latest lab results, he said. That’s because rains push water through the storm drains and creeks, and from Interstate 80, into Aquatic Park. The city will continue to monitor the situation closely, Chakko said, “just to get a better understand what’s happening there.”

Numerous community members have been looking for answers from the city in recent weeks about whether the dumping of human waste from RVs nearby might be raising bacteria levels in Aquatic Park. The issue has come up in the Berkeleyside comments section as well as during last week’s Parks and Waterfront Commission meeting.

Chakko said there is no proof of that happening at this time — and he said it might be difficult to determine that with any certainty.

“You could theoretically test the flow of water from every possible storm drain and see where it’s coming in,” he said. “It would be a very costly and expensive proposition to try and investigate all the possible sources of water.”

A member of the Berkeley Paddling & Rowing Club observed water coming into Aquatic Park one morning a week ago, and posted a video of it on YouTube.

YouTube video

Chakko said the city is aware of those reports and is looking into them.

Other community members have been testing the water for salinity and keeping a close eye on conditions themselves. Some have asked whether a nearby excavation project, north of Allston Way at Seventh Street, could be having an impact. There is East Bay Municipal Utility District equipment on site, as well as what appear to be water pipes, they have observed.

EBMUD said Friday evening that this was not its project, but could be a PG&E project. Berkeleyside will check with PG&E on Monday to learn more.

Chakko said he was not aware of that project as of Friday evening but could also look into it.

Community members have said the recent bacteria problems have made it critically important for the city to fix the tide tubes that run between Aquatic Park and the San Francisco Bay — which are largely blocked — to allow for a healthier water exchange between the two bodies.

In the meantime, the city is reaching out to groups that use Aquatic Park for recreation programs and is posting signs to warn of the potential health hazards associated with the water.

“We’ll keep testing and we’ll see if there’s a trend,” he told Berkeleyside..

Emilie Raguso (former senior editor, news) joined Berkeleyside in 2012 and covered politics, public safety and development until her departure in 2022. In 2017, Emilie was named Journalist of the Year...