Anderson Lake Closed Due to Toxins


JCPH Website

Nerve toxins in Anderson Lake
Reach Ninety Times Recommended Levels.

Elevated levels of the potent nerve toxin anatoxin-a were detected in a water sample taken from Anderson Lake on Monday, April 22nd. Test results were received from the laboratory on Monday, April 29, and the toxin level is 90 times higher than the Washington State recreational criteria. A bloom of toxin-producing cyanobacteria was found in the lake on April 1st, but toxin levels stayed below the recreational criteria until last week.

Exposure to anatoxin-a can result in illness and death in people and animals when ingested, even in tiny amounts. Washington State Parks has posted “Danger – Keep Out of Lake” signs at access points to the park alerting visitors of the hazard. Water-based recreational activities such as fishing, boating, and swimming are prohibited until the bloom dissipates and the toxin levels decline. Anderson Lake State Park remains open for other recreational activities such as horseback riding, hiking, biking and birdwatching.