Oklahoma City's ability to keep water flowing through the drought could take a hit if the U.S. Supreme Court sides with a Texas water district in a fight over southeast Oklahoma water.
The nation's highest court is to hear oral arguments in the case next week.
The Tarrant Regional Water District claims that a 1980 congressionally approved agreement, the Red River Compact, authorizes it to draw water from within Oklahoma.
Oklahoma says it has sole authority over use of water from streams within its borders.
In legal arguments filed with the Supreme Court, lawyers for Oklahoma City say the Texas water district wants to upend the basis of regional water management “because of Tarrant's opinion that North Texas needs the water more than Oklahoma.”
The compact allocates water from the Red River and its tributaries among Louisiana, Arkansas, Texas and Oklahoma.
Tarrant says on its website that it provides water for 1.7 million people in cities including Fort Worth and Arlington. Oklahoma City provides primary or backup water supplies to cities in central Oklahoma, with the potential to serve up to 1.3 million people.
In their brief, Oklahoma City's lawyers — from a Denver law firm — note the city's projected need for more water and its efforts to conserve through outdoor watering restrictions.