Blue-Green Algae Precaution for Diamond and Lemolo Lakes

Oregon Health Association has issued a precaution for Diamond and Lemolo Lakes, which will remain in effect until the visible bloom dissipates or is otherwise determined to be innoxious. At this time, weekly monitoring of Umpqua National Forest lakes this summer have not detected harmful algae blooms producing toxins at levels harmful to humans and pets. Conditions can change rapidly so lake users should continue to use caution when algae blooms are present. If cyanotoxins are detected in future monitoring an advisory will be posted on the Forest Facebook page and this webpage. For more information, please visit OHA website. 

What are algae blooms?

Blue-green algae (also called cyanobacteria) are found in water bodies throughout the world. An algal bloom is a rapid and massive buildup of algae cells that impart a green, milky white, or blue color to water. Under some conditions, particularly when winds are calm, some species produce a surface scum on the water. Conditions that favor development of blooms include warm sunny days and nutrient-rich water. Only certain species of blue-green algae produce toxins, and many of those species do not always produce toxins. The only way to know if a bloom is toxic is with specialized laboratory tests. Testing this summer has not detected toxins above public health advisory levels, but conditions can change rapidly so lake users should continue to use caution when algae blooms are present.

The most important way to protect yourself and your family from the health risks associated with toxic blue-green algae during a bloom is to avoid contact with the water. Activities near the water, such as camping, picnicking, hiking, bicycling, etc., are safe.

If you see an algal bloom, don’t drink the water. Filtering or boiling does not make the water safe to drink. Don’t get it on your skin and keep your children and animals away from the water.