Woodruff Narrows Reservoir: Harmful Cyanobacterial Bloom (HCB) Recreational Use Advisory

Wyoming Department of Environmental Quality  | view as a webpage

Wyoming Department of Environmental Quality

Woodruff Narrows Reservoir: Harmful Cyanobacterial Bloom (HCB) Recreational Use Advisory

The Wyoming Department of Health has issued a recreational use advisory for Woodruff Narrows Reservoir due to a harmful cyanobacterial bloom (HCB).

On July 11, 2019, satellite imagery from the Cyanobacteria Assessment Network (CyAN) identified elevated densities of cyanobacteria covering a large portion of the reservoir. The Wyoming Department of Environmental Quality visited the reservoir on July 17, 2019, and collected water samples at a beach on the west shore. Cyanobacteria densities exceeded the 20,000 cells/mL recreational use threshold identified in Wyoming’s Harmful Cyanobacterial Bloom Action Plan. Cyanotoxin results are pending. The most up-to-date information as well as other HCB resources can be found at WyoHCBs.org.

The Wyoming Department of Health is working directly with Wyoming Game and Fish Department and the Woodruff Narrows Reservoir Company to post advisory signs at the reservoir.

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

  • Avoid contact with water in the vicinity of the bloom, especially in areas where cyanobacteria are dense and form scums.
  • 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 and contact a doctor or veterinarian.

Questions about health effects and recreational use advisories can be directed to Karl Musgrave, State Environmental Health Epidemiologist / State Public Health Veterinarian, Wyoming Department of Health, at karl.musgrave@wyo.gov or (307) 777-5825.

Questions regarding cyanobacteria sampling can be directed to Michael Thomas, Natural Resource Analyst, Wyoming Department of Environmental Quality, at michael.thomas@wyo.gov or (307) 777-2073, or Lindsay Patterson, Surface Water Quality Standards Coordinator, Wyoming Department of Environmental Quality, at lindsay.patterson@wyo.gov or (307) 777-7079.