Water Quality

◄ Back
August 10, 2017

Anderson Lake toxin level high despite lack of visible bloom

The potent nerve toxin anatoxin-a remains above safe levels in Anderson Lake as of Monday, August 7, 2017. Washington State Parks is continuing the closure of the lake to boating, swimming and fishing. However, the appearance of the lake is deceiving: No algae bloom is visible and the lake looks remarkably clear. The toxin is produced by bluegreen algae, also known as cyanobacteria. The public is advised to respect the "Danger - Lake Closed" signs. The rest of the park remains open. For more information, see our lakes webpage at: