‘Harmful Algal Blooms’ discovered at Hyalite Reservoir

Town Crier “Briefs from the Region” (2) – 8/3/20

With warm weather comes “HABs,” or Harmful Algal Blooms, caused by blue-green algae native to Montana’s freshwater lakes and reservoirs. An algal bloom with the potential to produce toxins harmful to human health has been identified at Hyalite Reservoir in the Custer Gallatin National Forest. Not all varieties of blue-green algae are harmful, but some can produce dangerous toxins that can be fatal if ingested by dogs or small children. Blue-green algae blooms often look like pea soup, grass clippings or green latex paint. The Gallatin City-County Health Department is urging people to keep dogs and children away from HABs, which can be harmful or fatal in some cases. Direct contact, ingestion or inhalation of the algae toxins may irritate the skin, eyes, nose and respiratory system or cause nausea, vomiting, diarrhea or headaches.

“Children and pets are more likely to ingest HAB-infested waters because they spend most of their time wading in the shallow waters where algae can accumulate, and they have less control over how much water they ingest,” said Hannah Reidl, water quality specialist at the Montana Department of Environmental Quality.