Last week, Cowlitz County’s Health Department posted Level 2 cautionary signs around Silver Lake after a sample for algae toxins came back above the acceptable level for recreational water. An algae bloom was discovered while routinely monitoring the lake. Algae blooms are usually green and scummy, or give the water an overall green or blue-green color.
Some species of algae produce toxins that can be harmful to humans and pets if they swallow or come into contact with the water. The Level 2 cautionary signs clearly state that people and animals should stay out of the water. Symptoms of exposure to certain algae toxins include stomach cramps, vomiting, diarrhea, headache, blurred vision, convulsions, or severe muscle and joint pains. Additional test results for algae toxins are expected next week.
There have been no reports of illness in people or animals from contact with Silver Lake. Fish are safe to eat as long as they are cleaned well and the digestive organs are removed. Drinking water from public water systems or private wells in the areas around the lake is not affected by the lake water and is safe to drink. If you have physical symptoms, please see a health care provider.
The Cowlitz County Health Department will continue to monitor Silver Lake and will advise the public when water contact is considered safe again. Signs will be removed when the bloom dissipates and toxin levels are confirmed below safety threshold. Outdoor enthusiasts are encouraged to visit local Parks and Recreation web sites for information on other parks and boat launches.
More information on algae can be found at http://www.doh.wa.gov/ehp/algae. To contact the Health & Human Services Departments, please call 360-414-5599.