Residents asked again to avoid toxic algae blooms

It’s that time of year again when the Washington Department of Ecology asks residents near Lake Spokane and Newman Lake to keep children and animals away from the water because of blooms of toxic blue-green algae. The algae have spread widely in the Suncrest area, and could also be in other parts of Lake Spokane. Tests have been taken to determine the toxicity of the algae, but algae can change every day into a toxic or non toxic state. Results of the toxin analysis of a water sample taken from Lake Spokane near Suncrest on Monday, Sept. 20, 2010, are expected in about a week. “The sample results won’t be definitive,” said Mike Hepp, a water quality specialist in Ecology’s regional office in Spokane. “The toxicity changes all the time, so what we found on Sept. 20 may not be true today. The key is to stay away from it, don’t let kids play in it, and don’t let pets or livestock drink from scummy water. They are most at risk.” The sample is being analyzed for a toxin called microcystin. It is found most often in the scum that people can see on top of the water. As cells die, toxins are released into surrounding waters. Some toxins, such as microcystins, are very stable and can remain in the water for days or weeks after the bloom has disappeared. Although this outbreak is in Lake Spokane, an algae bloom also was reported in Newman Lake. This time of year blooms also are common at Potholes Reservoir and Liberty Lake. Algae blooms happen mostly in the summer or fall, but can occur anytime. Blue-green blooms can float to the surface and be several inches thick near the shoreline. Sometimes the blooms can be dispersed. They often look like green paint floating on the water. Blue-green algae blooms pose a human health concern and have killed animals after exposure in some Washington lakes. No illnesses have been reported from the current bloom in Lake Spokane. Although many blue-green blooms are not toxic, some blue-green algae produce nervous system or liver toxins. Toxicity is hard to predict. A single species of algae can have both toxic and non-toxic strains. People may become ill after contact with water such as swimming or water skiing in lakes with toxic blue-green algae. Human health effects may include stomach pains, vomiting, diarrhea, skin rashes, and nerve and liver damage. Blooms affect lake recreation, creating economic losses. Over the long term, Ecology has developed a water-quality improvement plan for the Spokane River and Lake Spokane that is designed to reduce algae by removing phosphorus in the water. Phosphorus acts like a fertilizer and actually increases the growth of algae and other aquatic plants. Decomposition of these plants robs the water of the oxygen that fish need to live.