Western water war

It has long been established that water rights on land managed by the U.S. Forest Service (USFS) and Bureau of Land Management (BLM) are subject to state law. But that doctrine might be at risk if the federal government gets its way in a lawsuit still brewing in southwestern Idaho.

That’s the word of the Denver-based Mountain States Legal Foundation (MSLF) that’s representing a group of Owyhee County, Idaho, ranchers and the Idaho Farm Bureau Federation. They are defendants in a recent motion by the federal government to overturn parts of Idaho law that allow ranchers to hold water rights on federal lands.

At issue is Joyce Livestock Co. v. United States , a landmark water rights case decided in 2007 by the Idaho Supreme Court. In that case, the court affirmed that Joyce Livestock Company of Murphy, Idaho, held water rights on federal land long ago obtained by grazing livestock.

The court ruled that the ranch’s water rights dating back to 1898 are “appurtenant” (legally attached) to the ranch’s deeded “base property.” The Idaho court further clarified that the federal government did not own cattle and therefore was not able to put the water to beneficial use—a main tenet of Western water laws.

The litigation continues

In response to its state Supreme Court ruling, the Idaho Legislature later codified these principles into state law. But early in 2022, the U.S. government sued the State of Idaho, arguing that certain state water fights statutes arising from the Joyce case were unconstitutional and discriminated against the federal government.

Related: How Mississippi River disruptions impact farm income and export competitiveness

In August 2024, a U.S. District Court judge in United States v. State of Idaho rejected the federal government’s attempt to block Idaho laws that allowed the forfeiture of “unused” federal stockwater rights. But in February 2025, the U.S. government responded with an appeal through the U.S. Ninth Circuit Court of Appeals—again declaring that pertinent parts of Idaho water rights law are unconstitutional.

On November 18, 2025, MSLF filed a reply brief in the U.S. Ninth Circuit Court asking for affirmation of the District Court decision. The appeal is now pending in the federal court system.

“The state of Idaho requires that anyone who has such rights put them to beneficial use by watering their own livestock,” said MSLF. “But right now the federal government is making an outrageous power grab to take stockwater rights away from Idaho.”

Far-reaching consequences

The state of Idaho began adjudicating water rights in Idaho’s Snake River Basin in the late 1980s. During this process, many ranchers considered claiming their stockwater rights on federally administered grazing allotments. But they were convinced by the federal government to assign their water rights claims to the BLM and the USFS.

Related: USDA names new APHIS leadership

Those ranchers, in effect, became “agents” of the federal agencies. But some ranchers didn’t buy into the BLM and Forest Service tactics—including the participants in the Joyce case. Meanwhile, organizations like the Idaho Farm Bureau are advising federal lands ranchers not to sign any more "voluntary agreements" with the federal agencies that might waive established water rights.

If the federal government succeeds, MSLF said the decision would jeopardize the ability of the ranchers to water their own livestock. The group said the federal government is almost certainly using Idaho as a test case that could be repeated in states across the American West.

Joyce Ranch owner Paul Nettleton warned that this case could affect every rancher who runs livestock on federal land—and even downstream private land.

“Even if you’ve got private water that you’re watering on your own land, that probably came off federal land to get to your private land,” he said.

“This would have far-reaching consequences,” MSFF added. “Not only would it be catastrophic to ranchers’ livelihoods, but it would be a blow to the ability of Western states to govern themselves.”

Related: Beef prices, policy and power