« Return to this article

Know the West

Latest: Wyoming to pay up over water dispute

A decade-old case on the Tongue River is resolved.


The Tongue River flows from Wyoming into Montana, providing water to farmers and ranchers. The 1950 Yellowstone River Compact governs how those states share it and three other Yellowstone tributaries. In 2007, Montana sued Wyoming for using too much water and violating the Compact, and the case landed in the U.S. Supreme Court in 2011 (“Where has Montana's water gone?HCN, 05/20/11).


In late February, the court ruled that Wyoming had shorted Montana nearly 1,400 acre-feet in 2004 and 2006 and ordered Wyoming to pay more than $38,000 in damages and interest, plus court costs of $67,000. If Montana places a “call” for more water, Wyoming must deliver it by ensuring that only users with water rights prior to 1950 are diverting or storing water. The decree should avert further wrangling over the Yellowstone Compact. "We are pleased to see this decade-long dispute finally resolved," Attorneys General Tim Fox of Montana and Peter Michael of Wyoming said in a statement.