Arizona Joins Nevada Lawsuit Against Federal Water Cuts

Arizona Joins Nevada Colorado River Lawsuit Against Interior Department

Arizona has officially joined Nevada in a lawsuit against the U.S. Department of the Interior to prevent forced federal cuts of up to 3 million acre-feet of water a year from Lake Mead. Arizona Katie Hobbs and the Arizona Department of Water Resources announced the legal action on Friday, seeking to compel the federal government to enforce water delivery obligations from Upper Basin states.

The state’s legal challenge targets aspects of a federal environmental review and decision that Arizona argues fails to require mandatory deliveries from Upper Basin reservoirs—Colorado, New Mexico, Utah, and Wyoming—into Lake Mead. Instead, the current federal framework places the burden squarely on Lower Basin states like Arizona, California, and Nevada.

“Arizona has always been willing to do our part to protect the Colorado River, but we will not accept a forced federal plan that solves this crisis on the backs of our families, farmers and businesses,” Gov. Hobbs said, as reported by news3lv.com.

Lower Basin Agreement and Central Arizona Project Stakes

State officials stress that joining the lawsuit protects Arizona’s legal rights while keeping the door open for a negotiated consensus among all seven basin states. The primary objective is to safeguard a two-year agreement established among Lower Basin states to conserve water specifically through 2027 and 2028.

The Lower Basin Agreement calls for Arizona, California, and Nevada to conserve more than 3.2 million acre-feet of water over 2027 and 2028 to stabilize the dwindling river system. Without this finalized agreement, Arizona officials warn that forced federal cuts could slash the Central Arizona Project’s Colorado River allocation by 77% over the next two years.

Of the total 3 million acre-feet in potential annual cuts contemplated by federal actions, Arizona faces the steepest loss. The state stands to lose 760,000 acre-feet—equivalent to nearly 250 billion gallons—each year over the next two-year period, according to state data reported by AZFamily.

State Leaders Clash Over Basin Responsibilities

Nevada Governor Joe Lombardo voiced support for Arizona’s entry into the legal battle, emphasizing the need for equitable burden-sharing across all state jurisdictions.

“I welcome Arizona’s partnership as we work toward a fair agreement that requires all seven Basin states to share responsibility for protecting the Colorado River,” Gov. Lombardo said. “We remain committed to a negotiated solution, but I will not allow Nevada’s interests to be pushed aside.”

Southern Nevada Water Authority General Manager John Entsminger noted that local water agencies remain dedicated to constructive dialogue with California and Arizona to finalize the near-term demand reductions on Lake Mead. In August, the Department of the Interior declined to formally adopt the Lower Basin Agreement, instead issuing a conservation plan that imposes a roughly 30% overall cut on Arizona, while leaving Upper Basin states exempt from mandatory water relinquishments.

Frequently Asked Questions About the Colorado River Legal Challenge

Why are Upper Basin states not facing the same water cuts?

Under the current Department of the Interior framework, mandatory water delivery obligations have historically placed heavier conservation burdens on the Lower Basin states—Arizona, California, and Nevada—while Upper Basin states including Colorado, New Mexico, Utah, and Wyoming are not currently required to give up water under the federal plan.

What is the Central Arizona Project and how does it factor into the lawsuit?

The Central Arizona Project is a canal system that delivers Colorado River water to the Phoenix and Tucson metropolitan areas. Without the protections sought by the state’s lawsuit and the preservation of the Lower Basin Agreement, CAP faces allocation cuts of up to 77% over the next two years.

How much water do Lower Basin states need to conserve under their local agreement?

The Lower Basin Agreement signed by Arizona, California, and Nevada calls for regional water users to conserve more than 3.2 million acre-feet of water over the course of 2027 and 2028 to stabilize Lake Mead.

Throughout this process, Nevada and the Lower Basin States have demonstrated that collaboration produces meaningful results, and we remain optimistic that the Colorado River Basin States can reach durable solutions that protect water users, support regional economies, and strengthen the resilience of the Colorado River for future generations, John Entsminger said.

More on Arizona: Arizona Law Enforcement Agencies Make 14 Domestic Arrests · Yuma Leads Arizona Cities in New National Snowbird Ranking