Parks and Recreation News

Watch for Blue-Green Algae

Post Date:July 13, 2018

Harmful Algal BloomsBlue-green algae are a type of bacteria present at low levels in many Minnesota lakes and ponds. When water is stagnant, warm and rich in nutrients — especially phosphorus — bacteria can grow quickly, forming what are called “blooms.” These blooms typically look like pea soup or bright green paint. They can also produce a strong, swampy odor as the bacteria breaks down.

Not all blue-green algae are harmful, but there is no way to determine if a water body is toxic just by looking at it. If there is algae visible in a body of water or if the water clarity is less than 3-feet deep, it is best to be cautious and avoid contact. Pets are particularly susceptible because they tend to swallow more water than humans while swimming. It is always a good practice to shower or rinse off after wading or swimming in lakes.

Click on the following links for more information from the Minnesota Department of Health and Minnesota Pollution Control Agency about blue-green algae and how to report potential blooms.

Blue-green algae: If in doubt, stay out 

Blue-green algae and harmful algal blooms

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