Potentially harmful blue-green algae has been found in Woodbury's Carver Lake.
Public health officials say people and pets should avoid contact with the water
"Not all blue-green algal blooms produce toxins; however, there is no way to predict if or when a bloom will produce toxins," the city said in a statement. "For this reason it is best to avoid contact and stay out of the water."
Toxic blooms of blue-green algae likely sickened at least one human and killed two dogs this summer.
While blue-green algae has been present in Minnesota since at least 1900, it's only been a matter of public focus in the past few years.
• Dogs as sentinels: Blue-green algae brings toxic mystery to Minn. waters
Since 2004, some 20 dogs have died from algae-related illness, and many people have been sickened by it.
Carver Lake, which has a popular suburban beach, was the site of a boy's drowning last month.