The U.S. Supreme Court held that the United States may pursue claims against New Mexico for violating the Rio Grande Compact, which Colorado, New Mexico, and Texas entered into in the 1930s to resolve disputes over water rights. Texas filed suit alleging that New Mexico was allowing its residents to...

The U.S. Supreme Court, in an unsigned judgment and decree, ordered Wyoming to pay Montana $20,340 in damages, plus $67,270.87 in costs, for reducing the amount of water available in the Tongue River in violation of the Yellowstone River Compact. The Compact protects pre-1950 appropriative rights to...

The Ninth Circuit upheld a lower court's dismissal of a tribe's NEPA challenge to a DOI guidance that did not consider its interest when allocating the water rights of the Colorado River. The tribe contended that it was unlawfully excluded from DOI 2001 and 2008 guidances that outlined how water is ...