Montana Department of Environmental Quality About Us Permitting & Operator Assistance Public Participation

Water Quality |Draft addendum to 2020 IR | Gallatin River, Yellowstone National Park Boundary to Spanish Creek| Public Comment Period Ends Aug. 22, 2022

DEQ to Host Public Meeting

  • Moira Davin
  • June 20 2022

Background: The Montana Department of Environmental Quality (DEQ) has completed a draft water quality assessment for a segment of the Gallatin River. DEQ completed the assessment after hearing concerns from local groups and receiving a petition to assess the Gallatin River.

This assessment of the Gallatin River indicates that the river is impaired due to exceeding thresholds for algae in 25 percent of the samples. The assessment is based on an evaluation of all readily available data collected within the past 10 years, including water quality monitoring performed by DEQ and the Gallatin River Task Force. Excess algae is often caused by an exceedance of thresholds for Total Nitrogen and Total Phosphorus. In this instance, the data do not show an exceedance of those thresholds. DEQ will need to determine what is causing excess algae in the Gallatin River and then develop a Total Maximum Daily Load (TMDL) or standards, as needed, to reduce the pollutants causing excess growth. A TMDL defines the amount of certain pollutants the waterbody can hold without impacts to water quality and beneficial uses of the river. 

In the meantime, DEQ has prioritized the lower Gallatin as a focused watershed. Focused watersheds receive additional funding and prioritization for restoration projects. Past projects in the Gallatin area have included stabilizing streambanks and creating wetlands to help reduce nitrogen loading and to reduce sediment in the river.

Associated Materials:

Comment Period Ends: August 22, 2022

Send/Submit Comments To:

Public Meeting Information:

  • What: A hybrid presentation on the draft Gallatin River assessment. 
  • When: Thursday, July 14, 2022 at 6 p.m.  
  • Where: The hybrid meeting will have both an online and in-person option. 
    • The in-person meeting will be held in Big Sky, Mont. at the Base Big Sky Community Organization (285 Simkins Drive)
    • To access the online or phone option:
      • Please click the link below to join the webinar:
      • Or via telephone:
        Dial(for higher quality, dial a number based on your current location):
        US: +1 213 338 8477 or +1 206 337 9723 or +1 646 558 8656
        Webinar ID: 859 4798 6043



Tags: Public Comment, Water, Public Meeting and Water quality

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