The Montana Department of Environmental Quality is investigating the cause of algal blooms along a section of the Gallatin River roughly 40 miles between the park and Spanish Creek. The agency is looking for the source of nutrient pollution, which can cause algal blooms that disrupt aquatic habitats and recreation.
Along that same river corridor is the community of Big Sky and other destinations that draw tourists, fishermen and outdoor recreationists. Andy Ulven with the DEQ’s Water Quality Bureau says there are a lot of different sources that could be contributing.
“There’s septic systems, there’s disturbance to some of the natural landscape, there’s roads that are built that have sediment that washes phosphorus into the stream when there’s a major storm,” he said.
A petition from environmental groups triggered the impairment declaration, which the U.S. Environmental Protection Agency approved last year.
The Montana Department of Environmental Quality says the entire process could take 5 or 6 years in total, with the goal of a cleanup plan and solution to the impairment.
Regulators will provide updates at a meeting Monday at 6pm in Big Sky and online.
