In one of the latest skirmishes, five Montana ranch owners filed a petition this week asking the Department of Natural Resources and Conservation to stop giving away water use rights for tens of thousands of new homes being built in areas once dominated by agriculture.
The ranchers' petition charges that the state's water rules are stacked against them.
The rules allow small wells used by each house within larger subdivisions to qualify for exemptions from state water laws. Those laws otherwise give precedence to the "senior" rights of farms and ranches.
That means dozens or even hundreds of homes can be built in the same general area without any water permits and regardless of the strain that added demand might put on underground aquifers.
Rancher Polly Rex characterized the exemption as a loophole that ultimately could rob her of the means to grow hay and water her livestock. Rex said a subdivision of more than 60 homes going up next to her Absarokee ranch could eventually draw down the natural springs she uses on an adjacent 1,250-acre field.
"I just really don't think I should change how I do our business because of somebody else," said Rex, whose water rights date to the late 1800s. "We simply cannot hand out water rights in thin air. It's a dumb way to do business."
DNRC spokesman John Grassy said agency attorneys were reviewing the ranchers' petition, which would require the state to revisit its water regulations. "The petition raises issues of statewide significance," he said.
The state rejected a similar petition from the Gallatin County Commission in 2006. Grassy said the water rules proposed by the county would have "completely halted development" across large areas of the state where all water rights already have been allocated.
Between 2000 and 2008, almost 30,000 exempt wells were drilled in Montana. During that period, the ranchers' petition claims, fewer than a dozen wells were drilled under state water use permits.
The exemption has been in place since 1993. It allows wells drawing up to 35 gallons per minute to be drilled without a permit.
Permits are needed only if at least two users are drawing water from the same well. The ranchers want that changed, so that two or more wells drawing from the same source would need a permit.
But in a rural state such as Montana, home builders often have no other realistic option, said Dustin Stewart with the Montana Building Industry Association.
Outside of cities, a developer's only alternative is to apply for a community well — a process that's too burdensome to be viable, Stewart said.
"The DNRC has made that process so long, so cumbersome and so costly, it's not an option except for the largest developer with the deepest pockets," he said. "Protecting Montana's ability to use individual water wells and build homes in a rural area is something we are willing to fight for."