Harmful Algal Blooms
Blue-green algae, also known as cyanobacteria, are bacteria that are naturally present in many water environments throughout Inyo County. Warmer temperatures, slow or stagnant water flows, and increased water-nutrient levels can cause these bacteria to flourish or 'bloom'. Thriving cyanobacteria can clump together to form floating mats on the water surface or present as a 'spilled paint' appearance. While many cyanobacteria do not cause issues, some are capable of producing toxins that can be harmful to humans and animals.
Throughout the warmer months, Inyo County EHD and the Lahontan Regional Surface Water Ambient Monitoring Program (SWAMP) conduct field investigations and testing in response to reports of suspected or ongoing blooms. The purpose of testing is to identify and quantify the species and toxins present. If the trigger levels for a particular toxin are exceeded, the appropriate tiered signage will be clearly posted at the affected waterbody.
If you suspect you've encountered an algal bloom, please use the link below to report observations, including any related human or animal illnesses. If you have questions, please contact the HAB Hotline: