Decades of industrial uses on the bay front along with storm-drain runoff have built up contaminated sediment.
But plans are under way to clean it up.
"We are coming to hopefully the end of a long, drawn out process to identify what actually is at the bottom of the bay and to devise a cleanup plan to get those responsible for making the bay dirty to clean it up," said Jill Witkowski, a staff attorney with San Diego Coastkeeper.
She said the California Regional Water Quality Control Board is considering proposals to cleanup portions of the bay.
"San Diego Bay, unfortunately, especially in this area where the shipyards have been operating for many years, has a toxic soup of a variety of different harmful metals and chemicals," said Witkowski. "Those include lead, mercury, copper, PCB's and other nasty substances that threaten both our ecosystem and human health."
Coastkeeper is hosting a panel discussion with experts on Tuesday, Aug. 9 from 6 p.m. to 9 p.m. at Memorial Recreation Center, 2902 Marcy Ave. San Diego, to talk about plans to remove toxic material from the bay.