DEQ to Host Public Meeting on Gallatin River Water Quality Study

The Montana Department of Environmental Quality (DEQ) will host an open house later this month to update the public on a multi-year study of water quality in the middle segment of the Gallatin River, stretching from Yellowstone National Park to Spanish Creek.

The public meeting will take place on Tuesday, July 29, from 5 p.m. to 7 p.m. at the Big Sky Center for the Arts, located at 77 Lone Peak Drive in Big Sky. Representatives from DEQ, the Gallatin River Task Force, Montana Bureau of Mines and Geology, and Montana State University will be on hand to answer questions and discuss progress on the ongoing study.

“We’re excited to celebrate the progress of DEQ’s study and our partners’ work on the Gallatin River,” said Andy Ulven, Water Quality Planning Bureau Chief at DEQ. “As we complete year three of data collection efforts this summer, DEQ would like to thank the other agencies and community partners who have invested significant resources and contributed to its success.”

The Gallatin River was officially designated as impaired for excessive algal growth in 2023, prompting DEQ to launch a six-year study focused on identifying sources of nutrient pollution. The goal is to develop Total Maximum Daily Loads (TMDLs)—scientific limits on the amount of pollutants a river can carry while still supporting uses such as agriculture, recreation, and aquatic life.

The study will culminate in the creation of a nutrient-algae model that sets thresholds for nutrient levels, which contribute to algal blooms. DEQ will then work with local stakeholders to implement a plan to protect and improve the river’s water quality.

By: DNU staff