By Finley Timon EDITORIAL INTERN
Regional nonprofit Upper Missouri Waterkeeper filed a lawsuit June 27 against the Montana Department of Environmental Quality. The group is challenging the state’s recent approval of phase two of the Quarry subdivision in Big Sky.
Waterkeeper alleges the DEQ used a new state law to approve the project without doing a full environmental review. That law, passed in 2023, allows some subdivisions with septic systems to skip pollution reviews that normally check for water quality impacts—at least temporarily until a Gallatin Canyon sewer is constructed, the Quarry development will treat wastewater using septic systems.
According to the group’s press release, the Quarry is located less than a quarter-mile from the Gallatin River, which is already listed as “impaired” under the federal Clean Water Act. That designation is due to algae blooms caused by nutrient pollution.
Waterkeeper claims the septic systems approved in phase two would release up to 11,500 gallons of treated wastewater per day into groundwater that flows into the Gallatin River. The group also said it submitted three scientific reports during the public comment period, but that the DEQ did not respond in a meaningful way.
“This lawsuit seeks to restore the constitutional guardrails around pollution control, and uphold the principle that development must prove it won’t harm Montana’s waters,” the press release stated.
‘Inconceivable’ approval
The Gallatin River Task Force, a Big Sky nonprofit focused on protecting the river, also supports the lawsuit against DEQ.
“We strongly support Upper Missouri Waterkeeper’s lawsuit against the Department of Environmental Quality challenging the state’s nutrient exemptions,” said Kristin Gardner, GRTF chief executive and science officer, in a phone interview with EBS. “It’s inconceivable that a major development like the Quarry subdivision could bypass a thorough, science-based environmental review to assess its potential impact on the Gallatin River. With increasing pressures from population growth and climate change, the Gallatin is at a tipping point. We cannot afford to gamble with a river that holds such profound ecological and economic value for our community and the region.”
Local business owners also voiced concern. In the Waterkeeper press release, Bill Zell of Montana Whitewater and Jason Fleury of Montana Troutchasers said poor water quality could hurt river health and the region’s outdoor economy.
“The health of the Gallatin River is integral to our business, livelihoods, and wellbeing. If the river continues to be damaged, it will deter visitors, costing jobs and revenue for our community,” Zell stated in the release.
Fleury added, “Using outdated septic systems for new development along already stressed rivers is reckless and short-sighted. We need pollution controls that protect clean water, not exemptions that greenlight more harm.”
The lawsuit does not involve the Quarry’s developer, Big Sky Rock, LLC. It focuses only on the DEQ’s approval process and the use of the new state law.
Representatives from Montana DEQ declined to comment for this story based on the lawsuit’s active status.
