The Wyoming Department of Environmental Quality has issued a warning about the rising dangers of a blue-green algae bloom in Cheyenne's Lower North Crow Reservoir.

The reservoir is located at the John and Annie Woodhouse Public Access Area 27 miles northwest of Cheyenne, and is used for irrigation purposes.

"Since this reservoir is not part of Cheyenne’s drinking water supply, the city’s tap water continues to be safe," said Board of Public Utilities Director Brad Brooks. "However, recreational use ... should be limited."

Blue-green algae blooms are considered harmful because they produce toxins and other irritants which can pose a risk to humans, pets, livestock and wildlife.

Residents are asked to follow these recommendations:

  • Avoid contact with water in the vicinity of the bloom, especially in areas where cyanobacteria are dense and form scum.
  • Do not ingest water from the 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 the bloom.
  • Do not allow pets or livestock to drink water near the bloom, eat bloom material or lick fur after contact.
  • If people, pets or livestock come into contact with a bloom, rinse off with clean water as soon as possible.

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