For generations, Montana families have relied on the waters of the Upper Clark Fork River to grow hay, care for livestock, and keep their ranches alive. In the high desert of Deer Lodge, where the growing season is short and every drop of water matters, access to irrigation is not a luxury—it is the foundation of a way of life.
Today, those families are fighting to protect that way of life.
Two radical anti-use organizations have sued a small group of Montana ranching families, claiming that their historic irrigation ditch violates the Endangered Species Act (ESA) because it may affect habitat for the threatened bull trout. Yet they have not identified a single bull trout that the West Side Ditch has actually injured or killed. In fact, the closest bull trout sighting was found more than 30 miles away from the farming operations.
Mountain States Legal Foundation has joined in this fight to defend these families because we believe Americans should not lose their property rights, water rights, or livelihoods based on speculation rather than proof. The Endangered Species Act was enacted to prevent actual harm to protected species—not to create a pathway for imposing liability based on uncertain predictions or theoretical impacts. It has never covered any species where there is no real connection between an action and genuine harm.
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A Way of Life Worth Defending
The West Side Ditch is more than an irrigation system. It is the lifeline for several small family farms and ranches near Deer Lodge, Montana, providing the water they need to grow hay, irrigate pasture, and feed the livestock that support their livelihoods.
Among them is the Pauley family.
Like many of the ranchers who rely on the ditch, the Pauleys aren’t running a massive agricultural operation. They own a modest family ranch, one of several small operations that have spent decades building a future they hoped to pass on to the next generation.
“My family is pretty much a first-generation family,” Dalton Pauley explains. “Lots of people are first or second generation. Maybe their parents started in the ’60s, and they worked their whole life just to have something. Now they’re fighting a lawsuit that’s really threatening their livelihoods because these properties just aren’t financially sustainable without our water rights.”
(Quote from American Stewards of Liberty)
For families like the Pauleys, irrigation isn’t about increasing profits. It’s about growing enough hay to feed cattle through Montana’s long winters. Without reliable access to water during the state’s short growing season, many of these ranches simply cannot survive.
But today, these families aren’t fighting drought or rising costs. They’re fighting a lawsuit.
Why These Families Are Being Sued
A coalition of anti-use organizations—Save the Bull Trout and Alliance for the Wild Rockies—claims that the families’ historic irrigation ditch operation violates the Endangered Species Act because it allegedly affects habitat for the threatened bull trout.
The Endangered Species Act was enacted to protect threatened and endangered wildlife from actual harm. It prohibits the unauthorized “take” of a protected species, including conduct that kills, injures, or otherwise harms the animal.
The plaintiffs argue that by diverting water from the Upper Clark Fork River, the West Side Ditch could affect bull trout habitat by changing streamflows, altering water conditions, making fish passage more difficult, or creating a risk that trout could enter the irrigation ditch.
But there is one problem with that theory.
No one has identified a single bull trout that the West Side Ditch has actually injured or killed.
Instead, the lawsuit asks the court to hold these families liable based on the possibility that their lawful irrigation practices could indirectly affect the fish or its habitat.
Why MSLF Is Fighting
Mountain States Legal Foundation exists to defend Americans whose rights are threatened by government overreach and abusive litigation. The families who rely on the West Side Ditch are exactly the people MSLF was created to protect.
The Endangered Species Act requires evidence—not speculation. It was written to address actual harm, not hold people liable for what might happen. MSLF is asking the court to reject an attempt to hold the West Side Ditch Company and the Pauley family responsible for harm they did not cause and allow the families to use their irrigation systems as they have for decades.
The stakes extend far beyond one irrigation ditch in Montana. If speculation alone is enough to create liability, the same theory could threaten farmers, ranchers, property owners, energy producers, miners, timber workers, and communities across the country that depend on responsible use of natural resources.
Case Timeline
- June 17, 2026: MSLF joins federal lawsuit to defend Montana ranching families whose long-established water rights and livelihoods are being threatened by a lawsuit alleging their historic irrigation practices could harm the threatened bull trout.
- September 4, 2026: A federal judge ordered the West Side Ditch Company and the U.S. Department of the Interior to stop diverting water from the Upper Clark Fork River whenever the river’s flow falls below 90 cubic feet per second. The order applies for the remainder of the 2026 irrigation season.