Larson Lake near Regent has been added to a list of 15 which have been impacted by blue-green algae.
A blue-green algae warning has been issued by the North Dakota Department of Environmental Quality Aug. 23 which added Larson, Froelich Dam (Sioux County) and Harmon Lake (Morton County) to the state list.
According to the agency, blue-green algae can produce cyanotoxins which could cause serious health impact to people and animals.
The lakes affected by the algae have been posted with warning signs.
With hunting season in the fall, bodies of water impacted by the algae can pose a health risk to hunters and their dogs, the agency warned.
People who swallow water containing cyanotoxins make become sick with diarrhea or vomiting and can display symptoms like numbness in the lips, tingling in fingers and toes, dizziness or rashes, hives and skin blisters.
In the areas of a lake where there is no evidence of a bloom, it can still be used for water-based recreation such as paddle boarding, water skiing, kayaking and swimming.
While fish are reportedly safe to consume, according to the department advisory, care should be taken to rinse hands with non-lake water after landing fish and wash the fish thoroughly with tap water before cleaning.
If people or pets get sick after swimming in the water, the agency recommended contacting a health provider and a veterinarian (if the pet is affected).