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Algae bloom found at Pritchard Beach; people and pets should stay out of the water

Staff from the King County Water and Land Resources Division of the Department of Natural Resources and Parks, doing routine testing, found an algal bloom in the water of Lake Washington at Pritchard Island Beach, 8400 55th Ave. S. Seattle Parks and Recreation is posting warning signs at the site on the advice of the Washington State Department of Health.

People and pets should not wade or play in the lake where scum from the bloom has accumulated. Dog owners should be especially cautious not to allow animals to drink from the lake in these areas. If there is water contact for a pet, it is important to rinse well to remove all algae.

The lake remains open to fishing, boating, stand-up paddling boarding and other recreational activities. Lifeguarded beaches at Pritchard Island Beach, Matthews Beach, Madison Beach, Mt. Baker Beach, Seward Beach, West Green Lake and Magnuson Beach are scheduled to open for the season on Saturday, June 25. Beaches at East Green Lake and Madrona Beach are already open.

An early summer-like spring has promoted the algae bloom, and recent warm weather continues to promote it.

Symptoms of illness from liver toxin are flu-like and may include abdominal pain, diarrhea and vomiting. If symptoms occur after ingesting lake water, park users should consult a health care professional immediately. Pets are at highest risk.

For more information on cyanobacteria, please visit the Washington Department of Health toxic algae website at The signs will remain in place until there have been two consecutive weekly tests with algae concentrations at a healthy level. The next test is on Monday, June 13.