BLM - Bureau of Land Management

08/22/2019 | Press release | Distributed by Public on 08/22/2019 14:16

BLM cautions public about algae blooms at Hauser Lake

(BUTTE, Mont.) - Though it may appear to be harmless 'green stuff' floating in the water, algae blooms can be toxic for humans and their pets. Working with Montana's Department of Environmental Quality, the Bureau of Land Management's Butte Field Office is cautioning visitors to Hauser Lake near Helena to avoid the algae, thick as pea soup, which has shown up at some of its sites.

No reports of illness have been reported at the BLM's Hauser sites, but Butte Field Manager Scott Haight said users should exercise caution when recreating in and around the water at Hauser Lake, particularly at its White Sandy Recreation Site.

'We have posted multiple signs at our facilities, advising people about what to watch out for and what to avoid,' Haight said, noting that no BLM sites have been closed due to the blooming algae.

Harmful Algal Blooms, or 'HABs,' are caused by blue-green algae native to Montana's freshwater lakes and reservoirs, according to a recent news release from Montana's DEQ. Potential causes include warmer water temperatures, longer summer growing seasons and increased nitrogen and phosphorus runoff from a variety of human activities. Under certain conditions, HABs can produce toxins that damage the skin, liver and nerve cells. They can make people and animals sick, and at worst, exposure can be fatal.
Not all varieties of blue-green algae are harmful, but some, under the right conditions, can produce dangerous cyanotoxins. Blue-green algae blooms often look like pea soup, grass clippings or green latex paint. The algae are usually suspended in the water column or aggregated into floating mats; they do not grow from the bottom as do roots, mosses or water plants.
Direct contact, ingestion or inhalation of cyanotoxins may irritate the skin, eyes, nose, throat and respiratory system, or cause nausea, vomiting, diarrhea, headache or liver and kidney damage. If you suspect a HAB-related illness in a person or animal, including livestock, call Poison Control immediately at 1-800-222-1222.
Learn how to report a suspected HAB at or call 1-888-849-2938. You may also report a suspected HAB by email to: [email protected]

For more information about the White Sandy site, contact the Butte Field Office at (406) 533-7600.