Cyanobacteria bloom confirmed at Keyhole

The Wyoming Department of Health has issued a recreational use advisory for Keyhole Reservoir due to a harmful cyanobacterial bloom (HCB).

On August 10, the Wyoming Department of Environmental Quality received a report from Keyhole State Park of dog illnesses that were potentially linked to cyanobacteria exposure. The Wyoming Department of Environmental Quality visited the reservoir on August 12 and collected water samples.

Cyanobacteria densities were found to exceed the 20,000 cells/mL recreational use threshold as identified in Wyoming’s HCB Action Plan. Cyanotoxin results are pendi...