Algae closes Lake Cassidy for swimming

Published 10:44 pm Friday, September 25, 2009

LAKE STEVENS — An algae bloom with high levels of toxins has made Lake Cassidy unsafe for swimming, Snohomish County authorities said.

The algae bloom has been ongoing since mid-August, but testing only recently showed the toxin microcystin at 100 times the safe levels, a county release says. The toxin can sicken people and animals. Health effects include stomach pains, vomiting, diarrhea, skin rashes and liver damage.

The county has posted signs telling people not to swim in the lake or drink the water. People also should keep pets away from the water, clean fish taken from the lake well before eating them, and avoid areas with algae while boating.

The 125-acre lake north of Lake Stevens and east of Marysville borders the Centennial Trail. The water typically appears brownish because of abundant algae, low water clarity and dense aquatic plants. The recent algae bloom shows up as green patches on the lake’s surface.