Blue-green algae blooms can resemble pea soup or green paint floating on the water. Harmful algae can be found everywhere in Minnesota, but they prefer warm, nutrient-rich water.
Certain varieties of blue-green algae produce toxins that can make you or your pets sick, but you can’t tell if toxins are present by looking at it. When in doubt, be cautious and avoid all contact with the algae.
There’s more than one kind of algae. The mat-forming, stringy-looking “filamentous algae” is common but nontoxic.
“When in doubt, stay out,” Water Resources Manager Bryan Gruidl said.
Though often referred to as algae, blue-green algae are not algae at all, but a class of bacteria called cyanobacteria.
Report potential harmful algae blooms to the Minnesota Pollution Control Agency at 651-757-2822. For more information on harmful algal blooms visit blm.mn/bgalgae, call 952-563-4870 or email engineering@BloomingtonMN.gov.