Well wars

With water rights dating to 1865, you wouldn’t expect Joseph Miller to worry about the security of his water supply. But to Miller, the new homes and subdivisions popping up in Montana’s Gallatin Valley, where he owns a 500-acre ranch, are plenty of cause for concern. Miller suspects those developments, which pump groundwater from permit-exempt wells, have dried up at least one stream on his ranch.

To address the problem, Miller and a few other ranchers recently petitioned Montana’s Department of Natural Resources and Conservation to stop letting residential developments use exempt wells to skirt the state’s water laws. They claim exempt wells will draw down water supplies that they have senior rights to.

In Montana, groundwater wells pumping less than 35 gallons a minute and no more than 10 acre feet a year don’t require a permit and aren't regulated under prior appropriation during drought. A 60-lot subdivision, for instance, can legally drill 60 wells into the same aquifer without permits or environmental review as long as those wells aren't connected. Even though the law says the exemption doesn't cover a "combined appropriation" by multiple wells from the same source if, together, they suck more than 35 gallons a minute, the state only considers wells that are physically connected by pipes to be a "combined appropriation."

"There’s really no protection in place for senior water rights," says Matthew Bishop, an attorney with the Western Environmental Law Center, which filed the petition on the ranchers’ behalf. Bishop says the state has known exempt wells are a problem "for a number of years," but "no one’s been willing to fix it."

"We felt we had to force the issue," he says.

According to the petition, there are some 200,000 exempt wells in Montana, a figure that could grow by as many as 78,000 wells in the next 10 years. The petitioners are asking the state the throw out its current interpretation of combined appropriation and initiate rulemaking to come up with a new one. According to Bishop, the state has 60 days to respond. If the petition is denied, he expects to challenge the state in court.

Meanwhile, a similar battle in Kittitas County, Wash., which I wrote about in October, is still dragging on.