08/05/2026
Cheyenne BOPU warns about chance of toxic algae blooms in Sloans Lake
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by Garrett Grochowski
Sloans Lake in Cheyenne, Wyoming. (John Roedel. Cap City News)
CHEYENNE, Wyo. — The Cheyenne Board of Public Utilities and Wyoming Department of Environmental Quality warned area residents Tuesday of the increasing chance of blue-green algae bloom in Sloans Lake. According to the Wyoming Department of Health, the algae can produce toxins and other harmful irritants.
Sloans Lake near Central Cheyenne is one of the city’s premier destinations for recreation. People are normally invited to float and fish in the water. While water from the lake is used for irrigation, it is not connected to the city’s drinking water supply.
The algae is known to bloom in the presence of sustained high temperatures in slow-moving water like lakes. After more than a month of high temps in the area, the algae could spread across the waterbody quickly. The bloom, according to the BOPU and the Wyoming DEQ, is expected to die off in late fall as temperatures decrease.
Algae bloom film (Cheyenne Board of Public Utilities Facebook)
“Once the bloom is no longer detectable, WDEQ will inform the Wyoming Department of Health, who will remove the advisory,” a statement from the BOPU said.
The algae is known to “produce toxins and other irritants that pose health risks to humans, pets, livestock and wildlife,” the warning states.
Residents and their pets should avoid the water and immediate area in the meantime, especially in areas where the algae has formed a dense film on the water surface. If someone catches a fish from the lake, they should clean it with fresh water sourced elsewhere.
People should not drink the water or let their pets drink or play in the water. If pets do get wet, rinse them thoroughly with clean water and don’t let them lick their fur, the BOPU said.
