07/10/2025
County staff suspect blue-green algae blooms on Lakes Bavaria, Eagle, Hydes, Parley, Reitz, Swede, Waconia, and Wasserman.
Though often referred to as algae, blue-green algae are not algae at all, but types of bacteria called cyanobacteria. These cyanobacteria can produce toxins that cause illness in humans and animals (like pets) if they are inhaled or ingested.
Blue-green algae prefer warm water with temperatures higher than 75°F and calm, sunny weather. The blooms are often blue-green in color, but can also be blue, green, reddish-purple, or brown.
There is no way to tell if a blue-green algae bloom has or is producing toxins just by looking at it. It’s best to avoid contact with the water and keep children and pets away too. The toxins can also persist after the bloom has disappeared so watch for green scum on the shorelines which may mean there was a recent bloom.
Staff suspect these blooms are blue-green algae, but the organisms can only be fully identified under a microscope. With a suspected blue-green algae bloom, avoid or minimize recreating in those waters. If you do come in contact, wash with fresh water afterwards.
Learn more https://www.pca.state.mn.us/air-water-land-climate/blue-green-algae-and-harmful-algal-blooms
