Contra Costa Health (CCH) advises caution on the part of anyone who boats, fishes or swims in or around Discovery Bay after large blooms of blue-green algae were discovered in multiple locations in and around the community.
A bloom is a buildup of blue-green algae, or cyanobacteria, that creates a green, blue-green, white or brown coloring on the surface of slow-moving waterways. Contact with a toxin produced by the bloom can make people and pets very sick.
The state Water Resources Control Board recently sampled water at Discovery Bay after a person and a dog, in separate incidents, each developed minor symptoms consistent with exposure to cyanobacteria toxin after contact with water in the community. Sampling revealed elevated levels of harmful algae.
CCH has provided caution signs to Reclamation District 800 to post at the marina in Discovery Bay. Everyone should follow the instructions on the signs and stay away from algae and scum in the water.
Keep children and pets on shore, away from the blooms, and do not touch or handle algae in the water or scum on the shoreline. It is also unsafe to drink or cook with water in these areas, or to eat fish or shellfish caught in or near them.
Visit cchealth.org/eh/hab to learn more about harmful algae blooms.
Visit mywaterquality.ca.gov/habs for more information and resources, including an online map showing where high concentrations of harmful algae have been reported across the state.