In Western water law, "first come, first serve" has limits

Three miles south of the Tongue and Yellowstone Rivers’ confluence near Miles City, Montana, an oxbow parts Roger Muggli’s alfalfa fields from the rough gray hills on the other side.  Most days, Muggli walks the diversion dam from the Tongue through ditches that feed water to his flood-irrigated crops.  He works the old-fashioned way: no sprinklers, no government handouts.  “If I can’t farm and make it on my own,” he says, “I’ll go do something else.”

Reservoir in Carter County, MT.  Courtesy of Flickr user, Justin Bugsy Sailor 

But loyalty to flood irrigation doesn’t make his job easy.  The labor is intensive, and sometimes the river simply won’t flow.  According to Muggli, drought is one reason his fields dry up.  The other culprit: Wyoming’s voracious water metabolism, stoked by central-pivot sprinklers, which irrigate crops far more efficiently than flooding but whose efficiency gains result in less water returned to the river, and the state's coalbed methane (CBM) operations, which withdrew 174 billion gallons of groundwater from the Wyoming Powder River Basin between 1987 and 2006.  (That’s enough to supply the American public for more than three years days.)

Like the other Montanans who farm the basin, Muggli has a stake in Montana v. Wyoming and North Dakota, the case that hit the Supreme Court on January 10.  Montana has accused Wyoming of drawing too much water from the Powder and Tongue Rivers and breaking the 1951 Yellowstone Compact.  According to the agreement, both states were guaranteed the water they already used before 1950.  Then, they divvied up the rest.

But in 2004, and again in 2006, a pre-1950 reservoir by the border in Montana dried up.  The state asked Wyoming to release water from storage, and both times, Wyoming refused.  That’s when Montana took their southern neighbor to court.

The most controversial claim—that advances in irrigation have caused Wyoming to consume more than its allotted share—raised eyebrows in the Supreme Court on Monday.  Chief Justice John Roberts referred to Western water law as “first come, first serve,” and suggested that it was “too bad for [Montana]” if technological advances in Wyoming’s irrigation system favored the upstream user.

“Sure, that is a fundamental principle of Western water law,” said Montana Assistant Attorney General Jennifer Anders, “but there are limits to that principle.”  The limit, in this case, is the Yellowstone Compact.  “An upstream user doesn’t get to increasingly expand their right to the detriment of downstream users.”  Montana, she says, does not aim to change Wyoming’s irrigation practices, but they do want Wyoming to release water from storage if the rivers are low.

But Wyoming officials believe the state is doing nothing wrong. Harry LaBonde, the Deputy State Engineer, attributes reduced river flow to drought.  And, he adds, sprinklers make sense—they take far less upkeep on the farmer’s part and allow crops to retain more water.

As of yet, no one seems to know exactly how much water Wyoming is using, nor how other uses, like CBM, are affecting the Basin’s hydrology.  Those numbers, attorneys say, are difficult to calculate—and they don’t plan to release them until certain legal issues are resolved. Anders says she has reason to believe that pumping groundwater from CBM wells reduces river flows into Montana.  But according to LaBonde, CBM wells dig too deep to affect Montana’s surface hydrology.

Though Montana has its own CBM reserves, the state has acted more cautiously than Wyoming where development is concerned.  There are 25-times more CBM wells on Wyoming’s side of the Powder River Basin than Montana’s, owing, perhaps, to a stricter regulatory environment, poor economics, and, as it seems to some Montanans, neighborliness. If Montana saw the same flurry of gas development, says Anders, “we would have to be mindful of any impact that may have downstream in North Dakota.”

Don’t expect to see a final ruling for a year or more—a long time for farmers like Muggli to hold their breath.  But, brassy and pragmatic, Muggli makes the dispute seem rather simple: “Once you get into things like compacts, you just can’t change the rules in the middle of the game.”

Sierra Crane-Murdoch is an HCN intern.