Texas filed a complaint Tuesday regarding the 1938 Rio Grande compact, which impacts water that flows through part of West Texas.
The Rio Grande compact demands that Colorado, New Mexico and Texas share water from the Rio Grande -- which flows through all 3 states.
However, Texas is accusing New Mexico of diverting some of the surface and underground water hydrologically connected to the Rio Grande downstream of Elephant Butte Reservoir.
Under the Rio Grande Compact, the diverted water is supposed to reach Texas, but the diversion takes place long before the river reaches the Lone Star State.
Texas filed the U.S. Supreme Court complaint after New Mexico allegedly started litigation to allow the water diversion to continue.