The heat of summer raises the risk of Harmful Algal Blooms (HABs). When HABs occur, they pose serious health hazards. The Gallatin City-County Health Department wants to make sure you, your family, and your pets stay safe while enjoying the lakes, rivers, and streams in and around Gallatin County.

The Gallatin City-County Health Department has been notified of a suspected HAB in Hyalite Reservoir, Hebgen Lake, Heather Lake in the Custer Gallatin National Forest, and in Elk Grove Pond, south of the Four Corners area. Water samples were collected and have been sent to labs for verification.

With HABs, conditions can change rapidly, and it is recommended to review the HAB
dashboard before visiting any water recreational area. It is also very important to read and follow any signage that may be present near a waterbody when you visit. If you see indicators of a HAB, follow the saying: When in doubt, stay out. Do not drink, swallow, or swim in water that shows signs of a HAB and keep kids, pets, and livestock out. Please visit the MT DPHHS website for more information on signage and guidance.

“As of the start of August, we’ve seen some caution advisories in Gallatin County,” stated Cameron Enright, Local Water Quality District Manager. “Hyalite Reservoir, Hebgen Lake, Elk Grove Pond, and Heather Lake are suspected as having the presence of possible toxic algae.”

HABs are hazardous for humans and pets. Serious illness or death can result from
drinking or swimming in contaminated water. Do not ignore signs that may be posted near any body of water.

HABs are a type of algae, known as cyanobacteria, that can create toxins. Ingestion or
prolonged contact with the algal bloom may result in illness, with impacts such as muscle twitching, staggering, convulsions, paralysis, and death. Microcystin, a harmful toxin produced by certain algae, was detected in the water sample from Elk Grove Pond.

Microcystis sp, a type of algae known to produce toxins, was also found in the sample.

Toxins were at or below the detection limit in the Hyalite sample, but Aphanizomenon sp, another type of algae that can produce harmful toxin, is suspected to be present.

Importantly, children and pets are more likely to ingest HAB infested waters. Direct
contact, ingestion, or inhalation of cyanotoxins may irritate the skin, eyes, nose, and
respiratory system or cause nausea, vomiting, diarrhea, or headaches. If you suspect a HAB-related illness in a person or animal, call Poison Control 1-800-222-1222 and seek medical attention.

Report a suspected HAB at www.hab.mt.gov or call 888-849-2938. You may also report a suspected HAB by visiting the Gallatin City-County Health Department’s website. For more information about, or to learn how to identify HABs, visit: Harmful Algal Blooms (mt.gov).

The mission for Gallatin City-County Health Department is to promote and protect health in the communities we serve. For more information, visit our website
www.healthygallatin.org.