Contra Costa County warns of toxic algae blooms

CLEARLAKE, CALIFORNIA - SEPTEMBER 26: Blooms of cyanobacteria, also called blue-green algae, cover the surface of the water in Clear Lake at Redbud Park on September 26, 2021 in Clearlake, California. Residents and visitors of Clear Lake, California'

Blue-green algae blooms have been spotted in multiple locations around Discovery Bay so Contra Costa County public health officials are advising anyone boating, fishing or swimming in the area to use caution.

The toxic algae blooms can cause people or pets to get sick if they contact them, and the state Water Resources Control Board recently sampled water in the area after a person and a dog both developed minor symptoms after being exposed to the cyanobacteria toxin in the blooms, according to Contra Costa Health Services.

The health department has provided caution signs to post at the marina in Discovery Bay, and people are asked to stay away from algae and scum in the water, as well as to not drink or cook with water from the area or eat fish or shellfish caught in it.

More information about the blooms can be found at