State agencies ask the public to report Harmful Algal Blooms -

State of Montana NewsRoom

Montana Government News


State agencies ask the public to report Harmful Algal Blooms

Thursday, July 19, 2018/Categories: Department of Environmental Quality,

HELENA – As we move full blown into summer, the public is urged to keep an eye out for Harmful Algal Blooms. HABs are a seasonal phenomenon on Montana’s lakes, reservoirs and ponds that can make people sick and even kill pets and livestock.


The Montana Department of Public Health & Human Services and the Montana Department of Environmental Quality are enlisting the public’s help with identifying suspected HAB sites. The agencies remind the public of the HAB reporting website – – as well as a 24-hour hotline at 1-888-849-2938.


Last year, the State HAB team verified 41 citizen reports of HABs for Montana’s lakes, reservoirs and ponds. Many of the reports were for Canyon Ferry Reservoir, Holter and Hauser Lakes on the Missouri. Other HABs were reported on Clark Canyon Reservoir, Beaver Creek Reservoir near Havre and Big Horn Reservoir, to name a few.


“Nationally, this issue is getting a lot of attention,” said Darrin Kron, DEQ Water Quality Monitoring and Assessment Section Supervisor. “However, it’s also a Montana issue. Last summer, Clark Canyon Reservoir had a confirmed HAB with alarming levels of cyanotoxins.”


“Harmful Algal Blooms can present a health risk to people and animals,” said Matt Ferguson, state toxicologist at DPHHS. “People may encounter HABs by drinking or swallowing water that comes from a lake or reservoir that has a toxic blue-green algae bloom or by swimming or other recreational activities in waters that have these toxic blooms. Swallowing water contaminated with these toxins may cause nausea, vomiting, diarrhea, headache or damage to the liver or kidney. Direct skin contact or inhalation of the toxic blue-green algae may cause irritation of the skin, eyes, nose or throat and people may experience respiratory symptoms after exposure.”


While not all varieties are harmful, some can produce dangerous cyanotoxins. Blooms of potentially toxic blue-green algae appear as "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 mosses or "water weeds." Algae blooms are in abundance this time of year on Montana’s ponds, lakes and reservoirs.


“Children playing near shore areas, as well as pets and livestock, may be at greatest risk for accidental ingestion of HAB infested water,” said Ferguson. “If you see water that is discolored or has foam, scum or mats of algae on the water’s surface we recommend that you do not drink or recreate in those waters. If you do recreate in water that might contain HAB, rinse off with fresh water as soon as possible afterwards. If your pet or livestock swallow water contaminated with HAB, call your veterinarian.”


Nationally, there have likely been no human deaths caused by HAB exposure; however, animal deaths, such as livestock, pets and wildlife have been caused by HABs.


“Along with educating folks about the danger, we’re asking the public to be our eyes out in the field so we can respond quickly and hopefully prevent people, pets or livestock from getting sick,” Ferguson said.


In addition to reporting basics, such as the time and date that an algal bloom is observed, the website allows users to upload photos of the bloom and pinpoint the GPS location. The site also includes the phone number for Poison Control, which should be called immediately if an HAB-related illness is suspected in a person or animal.


The Montana HAB reporting website aids the public with early identification. When an HAB is suspected, DEQ will investigate to determine whether an algal bloom is a cyanotoxin-producing species and whether levels are of concern. If the HAB is in a public lake or pond, DEQ or DPHHS will coordinate with the waterbody’s management, such as state or federal agencies or private landowners, to determine whether to issue a warning or closure of the waterbody. Over time, information gathered via the website and hotline will help the agencies with identification, early warning and prevention.


DEQ is involved in Montana’s HAB outreach and prevention efforts because it is the agency responsible for protecting Montana’s waterways from excess nitrogen and phosphorous –two nutrients responsible for sparking algal blooms. Scientists believe HABs are becoming more common and more toxic according to the federal Centers for Disease Control and Prevention.


This year, an unusually large algae bloom has filled Lake Okeechobee in Florida, covering 90 percent of the lake, and in 2014, an HAB in Lake Erie left nearly 500,000 residents of Toledo, Ohio without access to the public water supply for nearly three days. In fall 2015, an HAB covered 636 miles of the Ohio River, producing a toxin that can kill cattle.


How to report an HAB:


If you think a lake or pond shows signs of a Harmful Algal Bloom, keep children and pets out of the water. If you suspect an HAB-related illness in a person or animal, including livestock, call Poison Control immediately at 1-800-222-1222.


To learn more about HABs or to report a suspected HAB, visit:  Or call 1-888-849-2938. You may also report a suspected HAB by email:


Number of views (4527)/Comments (0)

Please login or register to post comments.