Murky, muddy mystery in Oakland Estuary water

People who live on the Oakland Estuary say for days the water has been unusually murky and muddy, and they’re not sure why.

Embarcadero Cove Marina is the spot where neighbors describe seeing the rust-colored water for days, despite the tides coming in and going out.

"It looked like clouds of mud rolling through the water," said Michael West. "Very brown and very muddy…not brown like after the rain, brown like something had been mixed into it."

For a decade, West has legally lived aboard his boat at the marina. He said after a couple of days of the suspicious water, his neighbors started wondering what was in the water, too.

The San Francisco Bay Regional Water Quality Control Board was initially unaware of any water quality problems, but tells KTVU there was a reported sediment plume near the Park Street Bridge earlier this week.

"This sediment is very unusual," said another resident who goes by Soul. "My concern is the animals. We have ducks, geese, all different types of birds."

Efforts to clean up the estuary and maintain water quality has been a priority in recent years, according to The Port of Oakland.

"We are now seeing greatly improved water quality and the evidence of that is the return of bird life and also marine mammals," said Richard Sinkoff, director of environmental programs and planning.

While the port did not receive reports of muddy, brown water, Sinkoff said it could be caused by any number reasons, including the hull of a ship scraping the bottom of the estuary and churning up mud.

Several large ships from the U.S. Coast Guard (USCG) are anchored at nearby Coast Guard Island in the estuary.

But a spokesperson with the USCG said any water quality-related issues have gone unnoticed.

"There could be many different sources so we would look to any illegal discharge that may be happening," Sinkoff said. "Maybe an overflow at one of the treatment plants."

While there is a nearby storm drain at the marina, the East Bay Municipal Utility District (EBMUD) and the City of Oakland both said they’ve had no sewage spills.

EBMUD said it would send a team to assess and monitor the water to make sure there’s no evidence of contaminants or a spill.

The regional water board also said it would visit the marina and areas of the estuary to make sure the water is safe, following KTVU’s questions.

While the dirty water has stuck around day after day, it was less noticeable Friday morning, according to those on the water. But Friday evening, as the tide changed, they report the murky water returning.

"No one here that I’ve spoken to, including people who have been living here 20 or 30 years have ever seen anything like it," West said. "Everything that happens out there on that water comes down here and stops."

Brooks Jarosz is an investigative reporter for KTVU. Email him at brooks.jarosz@fox.com and follow him on Facebook and Twitter @BrooksKTVU