Since 2018, the middle segment of the world-class Gallatin River has been plagued by widespread, noxious neon-green algal blooms. This scenic, wild, cold-water stretch of the Gallatin River is home to 3,000 wild trout per mile and supports recreational and guided floating, wade fishing, and family recreation. It’s just downstream from Yellowstone National Park and surrounded almost entirely by public lands, outside of development in the canyon and Big Sky area. The Gallatin River is part of our way of life and deserves to be protected now and for future generations.
Scientific studies have shown the Gallatin River to be particularly sensitive to nutrient loading; although chemical monitoring of nutrient concentrations in the Gallatin did not reflect consistent exceedances of numeric nutrient water quality standards, the Gallatin has experienced widespread algal blooms over the last four years as a direct result of sustained unnatural nutrient loading. Best available science indicates that algal blooms in the Gallatin watershed are driven by human-made nutrient pollution, particularly nitrogen. The largest sources of unnatural nutrients come from sprawl development and inadequate waste management practices in the Big Sky and Gallatin Canyon area.
Severe algal blooms degrade legally-protected recreational and aesthetic experiences and can negatively affect fish populations and aquatic communities by decreasing oxygen levels and compromising habitat conditions.
Because four consecutive years of severe algal blooms indicate a significant pollution problem, in March 2022 Upper Missouri Waterkeeper, Gallatin River Task Force, Montana Trout Unlimited, Greater Yellowstone Coalition, and American Rivers filed a petition with the Montana Department of Environmental Quality (DEQ) requesting a Category 5 impaired waterway designation of the middle segment of the Gallatin River under Section 303(d) of the federal Clean Water Act.
Montana is required to assess the state’s waterways and their health under the Clean Water Act. Any water body that doesn’t support its designated uses (ie. recreation, aquatic life) is classified as “impaired,” triggering the development of a Total Maximum Daily Load (TMDL), AKA a pollution diet. A TMDL is a planning tool used to identify pollution sources impairing the waterway and allocate necessary pollution reductions by source and sector to improve water quality.
DEQ’s Proposed Action
In response to the petition and years of monitoring data and visual evidence, in June 2022 DEQ granted the legal petition and made a preliminary finding that the Gallatin River is impaired by algal blooms and merits a Category 5 impairment designation and a science-based pollution clean-up plan. However, DEQ failed to identify nutrient pollutants as the key causal elements creating the Gallatin’s severe algal blooms.
What You Can Do
In order for the TMDL pollution diet and impairment designation to be effective at restoring the Gallatin’s health, DEQ must both (a) make a Category 5 impairment determination for the river, and (b) properly attribute nutrient pollutants as the key causal agents for algal blooms.
Take action and speak up for the Gallatin River! Send a comment to DEQ asking the agency to make the right decision for the river and clearly identify the source of pollution!