Temperatures are rising in SE Wyoming, and with the sunny skies and hot weather comes a dangerous development in lakes and rivers: blue-green algae.

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Although algae is a common sight in lakes and waterways and, in many cases, is completely harmless, some algae can be harmful to humans and animals. Unfortunately, the algae blooming in Lions Park's Sloan Lake is a more sinister species of algae called cyanobacterial blooms.

Dangerous Algae Blooms in Cheyenne's Sloan's Lake

According to a warning from the Wyoming Department of Health, harmful cyanobacterial growths have developed in Sloan Lake. The blooms are considered toxic because they can produce toxins and irritants that, when inhaled, ingested, or touched, can cause severe illness. The Wyoming Department of Health notes, "In extreme cases, cyanotoxins may lead to wildlife, pet, or livestock death."

Can You Still Boat or Fish in Sloan Lake?

Cyanobacterial growth should be approached with caution. Individuals and wildlife should not swim or wade in the lake, and water activities like boating should be approached with caution.

The Cheyenne Board of Public Utilities has issued the following advisories for visitors to the lake:

  • Avoid contact with water in the vicinity of a bloom, especially in areas where cyanobacteria may be dense and form a residue.
  • Do not ingest water where a bloom may be present. Boiling, using filtration, and/or other treatments will not remove toxins.
  • Rinse fish with clean water and eat only the fillet portion.
  • Avoid any water spray-off where a bloom may be present.
  • Do not allow pets or livestock to drink water near a bloom, eat bloom material, or lick fur after contact with a bloom.
  • If people, pets, or livestock come into contact with a bloom, rinse off with clean water as soon as possible.

Can You Tell If Blue-Green Algae Is Toxic by Sight?

No, you can't identify if blue-green algae are toxic by sight or smell. The only way to know is with lab tests or if you get sick. It's best to assume any algae growth is harmful.

What Do Cyanobacterial Blooms Look Like?

The Centers for Disease Control say cyanobacterial blooms can look like mats, scum, or foam on the water. It can also look like blue-green paint streaked on the surface or just below the water's surface.

For more information on Blue-Green Algae, visit:

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