Brown water in Oakland Estuary undergoing testing

For more than a week the Oakland Estuary has appeared brown, muddy and murkier than usual, prompting scientists to test the water.

The Port of Oakland sent out a dive boat and team of scientists Monday who say they found no sheen or file on the water to indicate oil or chemicals.

They said they observed the muddy, brown color and in some spots a slimy substance. Water samples were taken, which are now undergoing testing at an outside lab.

Several who live on or near the estuary told KTVU they have never seen the water look like this and were very concerned about potential health effects. Some expressed concerns over wildlife and marine mammals.

The San Francisco Bay Regional Water Quality Control Board sent someone to assess the water following questions and reports of sediment and the dark color.

A spokesperson said there is no odor or unusual feel to the water, and there are no reports of any toxic spills or sewage overflows.

Additionally, East Bay Municipal Utility District said it has no signs of issues with its sewage system.

All agencies said early indications suggest the change in the water could possibly be widespread algae blooms.

But it’s too soon to say for sure.

If it is determined these are toxic algae blooms, safety measures would immediately be put in place including issuing warnings to keep people off the water and away from the shoreline.

While the water board said it doesn’t think this is harmful, test results submitted by the port are expected to be returned by the end of the week – providing more clarity.

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