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November 8, 2010

Bullock to Defend Montana’s Right to Water Under Yellowstone River Compact

U.S. Supreme Court to hear argument over effects of irrigation in Wyoming

HELENA – On Monday, January 10, Attorney General Steve Bullock will defend Montana’s right to a fair share of the water that flows into the state from Wyoming in an argument before the United States Supreme Court.

The argument will resolve a long-running dispute between the two states under the 1950 Yellowstone River Compact. The issue before the nation’s highest court is whether Wyoming irrigators with pre-1950 rights can change their irrigation methods and, by doing so, decrease the amount of water that is available for uses in Montana that predate the Compact. Montana’s position is that the Compact obligates Wyoming to deliver a certain quantity of water under specified water supply conditions, and that quantity cannot be reduced by individual water users in Wyoming who change their irrigation practices.

The Supreme Court earlier appointed a fact-finder, known as a “Special Master,” to consider Wyoming’s motion to dismiss Montana’s Complaint and to conduct further hearings as needed. On February 10, 2010, the Special Master denied Wyoming’s motion to dismiss with respect to the majority of Montana’s claim. But, the Special Master recommended that the dismissal motion be granted in relation to Montana’s complaint that certain Wyoming water users with early rights were taking water that rightfully belonged to Montana. Montana argued they were doing this by adopting new irrigation techniques that decreased the amount of leftover water that flowed into our state.

In July, Montana filed an exception and brief to the Special Master’s ruling, insofar as it limits Montana’s ability to enforce the Compact under certain circumstances. The Court today set the date to hear arguments on this exception.

“Although Wyoming has historically disputed its obligations under the Compact, court officials have generally sided with Montana,” Bullock said. “On this one remaining issue, we believe that Wyoming — in violation of the Compact — is taking water from Montana users who have long-standing rights. We are pleased that the Supreme Court has agreed to hear arguments and we look forward to making our case in January.”

The Yellowstone River Compact protects pre-1950 water uses in Montana from later uses in Wyoming. In times of water shortage, this means that Wyoming must curtail water uses that began after the Compact was ratified whenever holders of pre-1950 water rights in Montana are not receiving sufficient water to satisfy their uses.

In his February 2010 First Interim Report of the Special Master, Special Master Barton Thompson, a professor at the Stanford University Law School, declared that the Yellowstone River Compact generally protects pre-1950 water users in Montana from uses in Wyoming that began after the Compact was ratified.

The Special Master’s opinion also said that:

  • Montana may sue Wyoming to enforce those water rights, and
  • Montana was correct in claiming that groundwater pumping — primarily associated with coalbed methane production in the Tongue and Powder River basins — may violate the Compact to the extent it is hydrologically interconnected to the surface channels of the Yellowstone River and its tributaries.

The case began in January 2007, when the Montana Department of Justice sued the State of Wyoming before the U.S. Supreme Court in an effort to protect the water rights allocated to Montana under the Yellowstone River Compact. Montana, Wyoming and North Dakota entered into the compact in December 1950, each state’s legislature ratified it and the U.S. Congress consented to the compact in 1951.