"The water flows from Diamond Canyon, down to I-580, all the way down to I-880, and here into the bay," says Sarah Pearce, a geomorphologist.
This is where rainwater from the Sausal Creek Watershed in Oakland enters the bay. A new report released Tuesday found what's being dumped into the bay contains high levels of PCBs, mercury and pesticides -- toxic runoff coming from city streets.
"There's still a legacy presence of PCBs throughout urban areas, especially the older areas, PCBs in buildings, but PCBs bio accumulate in fish to a level that make many fish unsafe to eat," says Thomas Mumley from the San Francisco Bay Water Quality Board.
Researchers tested creeks and storm drains in 15 industrial areas around the bay. Waterways near Richmond and San Pablo were found to be heavily polluted. Phil Malgren who works next to Rheem Creek in San Pablo says the community has tried to help.
"A lot of the stuff that you'd normally see floating around in this creek has been cleaned up and the water has seemed much cleaner," says Phil Malgren, a San Pablo business owner.
Plastic bags are another polluter. Neighbors living near a stretch of Glen Echo Creek in Oakland restored the creekside with native plants. The new plantings will actually help reduce the amount of contaminates entering the bay downstream.
"As the water slows down and all the sediment it is caring is really able to slow down and fall out of suspension and gets trapped back up in here, and so all the contaminants that are attached to that sediment are also trapped," says Pearce.
Researchers say while water quality in the bay has improved, more needs to be done and they are looking to the public for help.