CARBON COUNTY — As Montanans flock to lakes and reservoirs to escape the summer heat, state officials are warning about harmful algal blooms appearing in waterways across the state.
The blooms, caused by an overgrowth of cyanobacteria, can release toxins dangerous to both people and pets.
Watch state officials talk about algal blooms:
"It is an overgrowth of a type of organism called cyanobacteria," Montana Department of Enviornmental Quality, water quality specialist Tiffany Lyden, said Friday.
The blooms pose a particular risk to dogs.
"Their symptoms can be more severe and it can be really dangerous for dogs. If they've ingested a lot of water, it can be fatal for them," Lyden said.
At Cooney Dam in Carbon County, families are still enjoying the water. There is no active advisory for blue-green algae at the reservoir. Dahlia Bokma has made Cooney Dam a summer tradition.
"We come out here every summer, usually," Bokma said.
For her, the appeal goes beyond the water itself.
"It's a lot of fun. We don't often get to bring people other than our family together from camping, so when you get to have friends and stuff out here, it's a lot of fun," Bokma said.
Bokma said she has heard about the concern in Montana waterways.
"Isn't that the stuff that's not good for the environment? It can hurt a lot of the animals," Bokma said.
Lyden said blooms are common across the state this time of year.
"At DEQ we track citizen reports of harmful algal blooms and last year we had almost 60 reports around the state," Lyden said.
Lyden said the warning signs are often visible to the naked eye.
"If it looks like it's got spilled paint on it or the water looks kind of pea soup, or even like grass clippings on or in the water, that's an indication that there might be a harmful algal bloom going on," Lyden said.
Hot temperatures, calm water, and extra nutrients like nitrogen or phosphorus create the conditions for blooms to grow.
But Lyden said a bloom in one area does not necessarily mean an entire body of water is off limits.
"People can usually choose a different part of the lake to recreate on. Just because it's in one area of the lake doesn't mean the entire lake is off limits or potential for toxins," Lyden said.
For people, the health risk is typically less severe than it is for animals.
"Humans are a little bit less susceptible because we tend to be recreating in the water so that our exposure tends to be skin irritation," Lyden said.
