The Wyoming Department of Health is warning people about blue-green algae in the West Causeway of Granite Springs Reservoir.

Granite Springs Reservoir is located about 30 miles west of Cheyenne in Curt Gowdy State Park. The Causeway is just west of the reservoir where Middle Crow Creek flows toward the reservoir. The Causeway is separated from the main reservoir by a road.

Blue-green algae, also known as cyanobacteria. often forms toxic blooms in slow-moving water in the late summer months when the water is warm. The blooms release toxins and irritants that pose a risk to humans, pets, wildlife and livestock.

So far the cyanobacteria has not been found in the reservoir itself, which the Cheyenne Board of Public Utilities uses as a source for Cheyenne's drinking water. A BOPU news release says laboratory staff will continue to monitor water quality to make sure that it is safe to drink

The BOPU is also asking people to follow some precautions, according to the release:

  • 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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