Is it safe to swim in Clear Lake?
Lake County, Calif. (June 21, 2017) - There’s been a lot of talk recently about whether it is safe to swim in Clear Lake. There are two issues involved in the discussion. The first is the use of herbicides to control nuisance aquatic vegetation. From the County’s perspective and based on the environmental documentation prepared for the aquatic weed control program, the herbicides do not adversely affect the water for swimming. Tribal environmental offices may differ in their opinion of the program, but the County’s position is that the areas treated with the herbicides are safe for swimming.
The other factor currently affecting the lake is the widespread cyanobacteria bloom (oftentimes referred to as bluegreen algae). One can readily see the near-fluorescent green or blue shades of cells collecting at the surface. As dense as the surface coverage is, no bluegreen algal toxins have been detected. Monitoring is continuing as the situation could change. As a precaution, swimmers are advised not to consume raw lake water and dog owners should likewise restrain their pets from consuming or coming into contact with lake water as the dog may lick its fur. Swimmers should rinse off soon after getting out of the water.
Updates on the cyanobacteria blooms in California can be found at:
For more information please contact Carolyn Ruttan or Phil Moy, Director at Lake County Water Resources Department: (707) 263-2344.