U.S. Supreme Court awards damages in Montana-Wyoming water dispute

HELENA – The U.S. Supreme Court has ordered the state of Wyoming to pay Montana more than $38,000 in damages and interest and $67,000 in court costs in a long-running dispute over water rights that affect farmers and ranchers on both sides of the border.

Attorneys general for the two states said Tuesday’s decree provides clarity in implementing the 1950 Yellowstone River Compact as it applies to the Tongue River, discouraging future disputes.

“We are pleased to see this decade-long dispute finally resolved, and we look forward to continued cooperation between our states under the Yellowstone River Compact,” Tim Fox of Montana and Peter Michael of Wyoming said in a joint statement.

The order notes the compact “does not guarantee Montana a fixed quantity or flow of water, nor does it limit Wyoming to the net volume of water actually consumed in Wyoming prior to January 1, 1950,” when the compact agreement was reached.

Montana must place a “call” for water from Wyoming when it does not believe it is receiving adequate water under the compact or does not believe the Tongue River Reservoir near Decker will fill to capacity before the end of the water year.

Upon receiving a “call,” Wyoming must take action to ensure that only water users with pre-1950 water rights are diverting or storing surface water. However, Wyoming water users with post-1950 water rights are not required to give up previously stored water when Montana issues a call.

The order protects Montana’s right to store up to 72,500 acre feet, or 23.6 billion gallons of water in the Tongue River Reservoir each water year, which ends each Sept. 30.