Arizona hires law firm amid Colorado River water usage battle

After months of back-and-forth negotiations and two unmet deadlines over its rights to the Colorado River, Arizona is preparing for a legal battle.

The state hired a law firm following a dry winter along the basin, and high temperatures in March have already broken records. The pressure to maintain access to the state’s fair share of river water is growing.

On Monday, March 30, 2026, Arizona Governor Katie Hobbs’ office announced it hired the law firm Sullivan and Cromwell to represent the state in possible litigation among the Colorado River Basin states and the federal government. The international firm has represented big names like Microsoft, JPMorgan Chase, Goldman Sachs and more. Arizona is using some of the $3 million put into the legal defense fund last year to retain the firm.

Brandon Loomis, senior environment reporter for “The Arizona Republic,” joined “Arizona Horizon” to discuss Arizona’s potential legal battle.

“The day after they hired them, I listened in on a meeting of the other states, presumably of who might be the other opponents, and they seemed to think it was signaling,” Loomis said. “[They] said that litigation doesn’t solve water problems, so they heard the message.”

For over two years, the lower basin states, namely Arizona, Nevada and California, and the Upper Basin states, which are Colorado, New Mexico, Utah and Wyoming, have been negotiating an updated water usage agreement.

“[Arizona] has been trying for years to get a deal with the other six states and it just hasn’t worked,” Loomis said. “If it ends up going to court, my understanding, is that it would be based on the 1922 Compact.”

In 1922, the Colorado River basin was legally split into two sections, the Upper Basin and the Lower Basin, in what came to be known as the Colorado River Compact, according to Congress.

The Governor’s office doesn’t expect any legal action until June 2026 at the earliest, however they want to be prepared if the dispute ends up before the United States Supreme Court.