What is this lawsuit about?
This case is about government transparency, public participation, and environmental accountability. It challenges DEQ’s June 2025 approval of a new sewer pipeline in Big Sky that was authorized without any public notice, opportunity for public participation, or environmental review, violating the Montana Environmental Policy Act and constitutional guarantees to public notice and participation opportunities before government decision-making.
At its core, this case begs the question: should large wastewater infrastructure projects with potentially significant impacts on our waterways be approved behind closed doors, or should there be open and transparent public processes, scoping, and review? We believe the law clearly requires the latter.
Why was a legal challenge filed now if the pipeline was approved in June 2025?
Montana law provides the public 30 days to file a legal challenge once they know, or reasonably should have known, that the government failed to provide legally required public notice or participation.
In this case, the approval of the sewer pipeline only came to light after we filed a Right to Know request concerning what wastewater infrastructure decisions DEQ was considering, and received documents that disclosed DEQ’s after-the-fact decisionmaking. We received those documents on November 17, 2025, so our December 17 filing was within the 30 day deadline.
What did the Right to Know request disclose?
Documents received through the public records request revealed that DEQ approved a deviation request for “Big Sky Canyon Area Lift Stations, Forcemain, and Reuse Pipeline” project on June 8, 2025. The application in support of the deviation specifically stated the overarching Gallatin Canyon Sewer Project would likely stop if the pipeline deviation was not approved.
Prior to approving the deviation for the pipeline, DEQ did not provide for any public notice or public participation opportunities, nor did it draft or publish any environmental reviews of the project or connected actions that are currently being reviewed by the Department.
It is also worth noting that among the documents disclosed by the agency was an extensive record of years of dialogue between DEQ and local sewer districts about what has been named the Gallatin Canyon Sewer Project, meaning DEQ has been well aware of the role that the pipeline plays in the larger wastewater treatment and disposal scheme, and therefore, has no excuse for why it is treating the pipeline in isolation rather than viewing the pieces as a whole.
What exactly was approved by DEQ?
DEQ approved an approximately 5,000-ft sewer pipeline adjacent to Highway 64 and stretches of the West Fork of the Gallatin River in Big Sky. The pipeline is designed to allow wastewater to be transported between Big Sky’s Canyon Area and the Meadow wastewater treatment facility.
The Pipeline Project is self-described by the application as a first and essential component of the Gallatin Canyon Sewer Project.
DEQ’s engineering rules require a 10’ separation between a forcemain and reuse pipeline, but the Pipeline Project cannot proceed without a deviation from this requirement because of limited space along Highway 64 and the unwillingness of private land owners, Montana Department of Transportation, or the Forest Service to allow different pipeline routes. DEQ approved the deviation, allowing less than 10’ separation between the two pipelines, and placement of roughly one mile reach of pipeline adjacent to the W Fork Gallatin River and Hwy. 64.
Because, by the deviation application’s own language, “the project will potentially cease if a deviation is not granted,” the approval of the deviation is a greenlight for a new regional wastewater conveyance system that will support a new municipal-scale sewage discharge permit in Big Sky’s Canyon Area. In fact, email communications released in the records request show DEQ was considering a discharge permit application from the same applicant.
Despite the inextricable connection and significant character of these major sewage infrastructure projects, DEQ never connected the dots between its public trust responsibilities or provided notice of its consideration or proposed major sewage infrastructure decisions.
How was the law broken?
1. DEQ violated Montanans’ Constitutional Right to know and right to participate in government decisionmaking by approving the Big Sky sewage pipeline behind closed doors, without any public notice or comment opportunities.
2. DEQ failed to perform any comprehensive environmental analysis.
3. DEQ informally deemed the pipeline project “nonsignificant” and exempt from public participation or Montana Environmental Policy Act (MEPA) processes, thereby violating core public participation and information gathering requirements of MEPA.
Has this happened before?
Yes. Analogous agency pattern and practice of withholding public participation has been documented twice recently in Gallatin County.
One District Court has found that refusing to do meaningful MEPA and public participation of gravel pit mining is unconstitutional and unlawful.
Another District Court judge has also issued a preliminary injunction, an indication that Waterkeeper is likely to succeed on the merits of a case where DEQ refused to provide any public participation opportunities on an entire wastewater system in West Yellowstone.
Despite these two recent rulings, DEQ continues to do the same thing those courts deemed unlawful, making it all the more important that we hold the agency accountable for following the law and providing transparent government decision-making.
What is the purpose of MEPA?
The purpose of the Montana Environmental Policy Act (MEPA) is to “declare a state policy that will encourage productive and enjoyable harmony between humans and their environment, to protect the right to use and enjoy private property free of undue government regulation, to promote efforts that will prevent, mitigate, or eliminate damage to the environment and biosphere and stimulate the health and welfare of humans, to enrich the understanding of the ecological systems and natural resources important to the state…” (75-1-102(2), MCA).
Essentially, MEPA is designed to provide informed decisionmaking through public transparency and participation and thorough environmental reviews.
Why does public participation matter?
Public participation is legally required under Montana law, and explicitly guaranteed Montanans as part of our state constitution. Traditionally state agencies like DEQ implement public notice and environmental scoping pursuant to the Montana Environmental Policy Act, a process through which the public and decision-makers learn about projects, raise concerns, and identify environmental impacts – especially cumulative impacts that agencies or engineers often overlook. In the end the process is about understanding the consequences of our proposed actions so we can make informed decisions.
Without public disclosure, scoping, or an opportunity to comment, the public can’t assess whether a project is actually beneficial, harmful impacts can be overlooked, and agencies can’t gauge public concern, itself a factor for requiring more robust scrutiny of a controversial project. Approving major wastewater infrastructure projects without public participation undermines democratic decisionmaking, can omit consideration of potentially significant impacts and viable, less-harmful alternatives, and violates the public’s right to know and right to participate.
Why is an Environmental Impact Statement (EIS) appropriate?
An EIS is required when a project may significantly affect the environment. This case involves significant generational costs and municipal scale wastewater infrastructure, connected actions under concurrent review by an agency, potentially significant cumulative impacts to an impaired river, and high public interest (over a thousand citizens submitted public comments supporting the Gallatin River impairment designation) – the combination of which undoubtedly merit a robust environmental review best achieved through an EIS. An EIS will help DEQ understand the consequences, alternatives, and long-term outcomes of the project, and better engage core constituencies such as local governments faced with pressure to approve large-scale development projects in unincorporated, unzoned, yet nearby county lands.
What is being requested through this litigation?
The litigation requests that the Court:
- Order DEQ to conduct a comprehensive EIS of sewage infrastructure planning;
- Reverse the pipeline approval and mandate public participation opportunities;
- Declare that DEQ must perform MEPA analyses and provide public participation opportunities when receiving water infrastructure project applications.
Is the goal of this lawsuit to shut down the pipeline?
No, this lawsuit is not about stopping the pipeline project. This lawsuit is about ensuring informed, transparent decisionmaking before investments are made and dirt work has been begun.
The desired outcome of the lawsuit is to force DEQ to reconsider the full suite of regional wastewater infrastructure being proposed in Big Sky through a comprehensive Environmental Impact Statement (EIS) and a meaningful public participation process.
We aren’t opposed to a pipeline outright, and we definitely support improving wastewater collection and higher levels of treatment for legacy polluters. However, those laudable goals do not mean government can authorize massive infrastructure decisions behind closed doors, paid for with tax dollars, without transparency, public input, or a full understanding of environmental consequences.
What is DEQ’s stance on environmental review for infrastructure projects?
Typically, DEQ conducts scoping for big and controversial decisions about massive infrastructure projects, such as mining operations or new industrial scale activity. Scoping allows the public to know what’s being proposed and why it’s good or bad, and provides an opportunity for the public to raise concerns or voice support. For the Pipeline Project, DEQ failed to provide any opportunity for public involvement, and failed to disclose the interconnected nature of the pipeline to the related discharge permit application adjacent to the Gallatin River.
Why is the pipeline environmentally significant?
The planned pipeline would transport sewage and treated effluent alongside the West Fork Gallatin River, a sensitive area that is already nutrient-impaired. This by itself is a calculated risk with serious consequences if pipelines ruptured. Similarly, the pipeline serves a specific purpose of wastewater disposal in the Canyon Area. It would enable hundreds of thousands of gallons of treated wastewater per day to be disposed of near the Gallatin River. The pipeline is a key component of a broader wastewater disposal strategy that could introduce new nutrient pollution into an already impaired watershed without any guarantees – much less affirmative science – showing this will restore the Gallatin.
When considered in totality, the cumulative impacts of the Gallatin Canyon Sewage Project could further threaten water quality, fisheries, recreation, and downstream drinking water. As such, there needs to be more sunlight on all aspects of government decisions-making, including a pause on all infrastructure decisions.
Isn’t approving a pipeline just an engineering decision?
No. DEQ has taken the position in several other legal cases that infrastructure projects meeting its engineering standards are automatically “nonsignificant” and therefore exempt from MEPA review and public participation. This argument is contradicted by law and science.
Engineering standards are not designed to evaluate direct, indirect, or cumulative impacts. A project can meet engineering standards and still contribute to environmental harms, especially when combined with other projects.
Furthermore, the pipeline is not a standalone engineering decision; it is an inseparable part of a larger connected regional wastewater conveyance and disposal system that must be reviewed as a whole.
What are connected actions and why do they matter?
Connected actions are projects that are linked by purpose, timing, or impact, and must be reviewed together under MEPA.
In this case, the pipeline is inseparable from a pending wastewater discharge permit for the Canyon Area, regional wastewater disposal planning, and future development in the Big Sky region. DEQ cannot lawfully segment or bifurcate review by claiming the pipeline is just engineering. The law requires consideration of the whole system and its cumulative impacts.
How does this relate to Big Sky’s wastewater treatment upgrades?
Big Sky has a new Wastewater Resource Recovery Facility that uses membrane bioreactor technology that offers improved treatment and increased capacity above the older plant built in the 1990s. However, the new facility is treating wastewater to Level A-1 standards, which are antiquated wastewater re-use standards in Montana’s pollution control rules. There is no science demonstrating that injecting hundreds of thousands of gallons of A-1 wastewater each day into the Canyon Area will assure protection of the Gallatin River or stop the recurring algal blooms. In fact, a strong body of evidence suggests allowing such new discharges will contribute to the problem, not solve it, especially without guarantees of eliminating legacy nutrient pollution sources.
Waterkeeper fully supports higher levels of treatment and centralized wastewater treatment, but A-1 falls short and is likely to exacerbate existing pollution issues.
What is the concern with groundwater disposal in the Canyon Area?
The proposal relies on disposing of large volumes of treated wastewater into groundwater in the Canyon Area, based on the assumption that meeting A-1 treatment standards is sufficient.
Montana Bureau of Mines and Geology’s recently published groundwater study confirmed clear hydrologic connections between groundwater and surface water in the Upper Gallatin River. Likewise, DEQ’s approval of the major community septic systems in the Canyon Area admits each of those areas – which are now proposed for diffuse disposal of more wastewater under the Gallatin Canyon Sewage Project – contains groundwater that funnels wastewater discharges into the downgradient Gallatin River.
The addition of thousands of gallons of new wastewater in the Canyon’s groundwater has the potential to contribute to unhealthy algal blooms that are already degrading the Gallatin River, and further necessitates an environmental impact statement.
What does the Gallatin River’s impaired status mean?
The Gallatin River has an EPA-approved impairment designation for algal blooms, which are caused in part by excess nutrient loading. Under the federal Clean Water Act, no new pollution sources are to be permitted until a Total Maximum Daily Load (TMDL), or “pollution diet” has been developed, which DEQ estimates will take 4-6 years. Until then, the river has no remaining assimilative capacity for additional pollution. Authorizing new wastewater discharges before this process is complete puts the river at increased risk of pollution.
Moreover, federal law prohibits new point source discharges of pollutants related to a river impairment pending completion of a TMDL. It sure seems fishy when our government and polluters are proposing small bite-size portions of major sewage projects such that by the time any future public notice or analysis occurs the project is a foregone conclusion. Likewise, its more than a coincidence to review emails between a state regulator and permittees actively cooperating to review sewage infrastructure projects under the least restrictive state rules, as opposed to the more restrictive federal regulations.
As Mark Twain was fond of saying, there are three types of lies: lies, damned lies, and statistics. Sadly it is up to the public to hold our government accountable to put all the cards on the table and allow the public a meaningful opportunity to comment on the enormous significance of a regional wastewater disposal plan for Big Sky and the Gallatin River.
Why does this matter beyond Big Sky?
This case has statewide implications. It challenges a growing pattern and practice of DEQ approving major water infrastructure projects without MEPA review or public participation.
Allowing agencies to ignore transparency mandates under law and required by our constitution sets a dangerous precedent for our rivers, communities, and democratic governance across Montana. The public has a right to know what is being proposed, understand environmental, social, and economic impacts, and participate meaningfully in decisions that affect our shared water resources.