Cyanobacterial Blooms Can Still Pose Risks as Wyoming Gets Colder

While the weather is getting colder and swimming isn’t on most people’s minds, the Wyoming Department of Environmental Quality wants to ensure everyone avoids the hazards still posed by harmful cyanobacterial blooms.

The department issued recreational use advisories for 21 Wyoming lakes and reservoirs throughout the 2020 season, including advisories at the Buffalo Bill Reservoir in Buffalo Bill State Park and the Weston Reservoir in Bighorn National Forest. The advisories for all the affected waterbodies ended on Sept. 30, but that doesn’t mean the blooms have vanished.

Most cyanobacterial looms tend to occur during the warmer months of summer and fall and typically dissipate as temperatures decrease. Some are known to persist longer, even into freezing temperatures. This means they still pose health risks to anyone that may encounter them.

The Department of Environmental is primarily concerned with hunters and fishermen who may encounter a persistent bloom in one of the 21 waterbodies where advisories were in place earlier this year.

The Wyoming Department of Health and Wyoming Livestock Board continues to recommend the following:

• Avoid contact with water in the vicinity of blooms, especially in areas where cyanobacteria are dense and form scums.
• Do not ingest water from a bloom. Boiling, filtration, and/or other treatments will not remove toxins.
• Rinse fish with clean water and eat only the fillet portion.
• Avoid water spray from a bloom.
• Do not allow pets or livestock to drink water near a bloom, eat bloom material, or lick fur after contact.
• If people, pets, or livestock encounter a bloom, rinse off with clean water as soon as possible and contact a doctor or veterinarian.

The department continues to receive updates on bodies of water where harmful cyanobacterial blooms were identified but won’t issue any more advisories this year. It’s primarily up to the individuals in the vicinity of a harmful cyanobacterial bloom to be aware of their risks and avoid them entirely.