Keyhole Reservoir under investigation for cyanobacterial bloom

A concerned visitor alerted Wyoming State Parks that their pets became ill after a recent visit to Keyhole State Park. Out of an abundance of caution, park staff posted warning signs and contacted the Wyoming Department of Environmental Quality (DEQ).  That agency is proceeding with an investigation of a potential harmful cyanobacterial bloom (HCB). 

The investigation is currently only for the section of the reservoir in the upper end of Cottonwood Bay, potentially affecting Pronghorn, Tatanka, Arch Rock, Cottonwood and Homestead campgrounds.  

Recent and repeated satellite imagery does not show the presence of HCB, and park staff have visually surveyed the potentially affected areas on land and from the reservoir, and have not seen any evidence of a bloom. DEQ is sending staff to investigate, and the Wyoming Department of Health has been alerted.

Lakes or reservoirs under investigation are not closed. Marinas, lakeside parks and camping facilities are open for business. Any closed areas will be specifically noted. Visitors are advised to err on the side of caution and use their best judgment when recreating in this area.