Arizona Joins Nevada Colorado River Lawsuit Over Water Cuts

• Arizona has formally joined Nevada's lawsuit challenging the Bureau of Reclamation's decision to impose significant Colorado River water cuts.
• The lawsuit alleges the federal government failed to hold upper basin states accountable for water delivery obligations, placing the entire burden of cuts on lower basin states.
• Arizona faces a total reduction of over 1.8 million acre-feet by the end of water year 2028, while no mandatory cuts were imposed on upper basin states.
• Nevada's initial lawsuit, filed in August, claims violations of the Administrative Procedure Act, National Environmental Policy Act, and the Law of the River.
• The litigation seeks to protect Arizona's legal water rights and challenges the federal plan's disproportionate impact on lower basin communities and economies.

Lawyers advising clients in the Lower Basin states on water rights, real estate, or agricultural operations should closely monitor the progress of this lawsuit, as its outcome could significantly alter future Colorado River water allocations and compliance requirements.

Arizona has officially joined a legal challenge initiated by Nevada against the Bureau of Reclamation's recent decision regarding Colorado River water allocations. This move comes approximately eight weeks after the federal government implemented significant reductions to Arizona's water supply from the river. Governor Katie Hobbs and the Arizona Department of Water Resources contend that the Bureau failed to enforce water delivery obligations on the four upper basin states, thereby placing the entire burden of the federal cuts, imposed in August, solely on the three lower basin states.

The federal plan mandates that the lower basin states—Arizona, Nevada, and California—collectively reduce their water usage by 3.5 million acre-feet over the next two years. Arizona is slated to bear the largest portion of these cuts, amounting to 760,000 acre-feet annually for two years. When combined with an additional 300,000 acre-feet in voluntary conservation efforts, Arizona faces a total reduction of over 1.8 million acre-feet by the conclusion of water year 2028. Notably, the plan does not impose any mandatory cuts on the upper basin states, which include Colorado, Utah, Wyoming, and New Mexico. These states had previously declined mandatory reductions, citing their senior priority rights under the complex framework known as the Law of the River.

The decision by Arizona to join Nevada's Colorado River lawsuit stems from a long-standing dispute and a perceived imbalance in federal water management. Governor Hobbs asserted that Arizona is prepared to contribute to the river's protection but will not accept a federal plan that disproportionately impacts its residents, agricultural sector, and businesses. She specifically criticized the federal government for not holding the upper basin accountable for water deliveries owed to Arizona, suggesting the imposed cuts go "well beyond the Lower Basin Agreement." This agreement, a collaborative effort among Arizona, California, and Nevada, aims to safeguard the river and prevent future federal interventions that could severely diminish allocations, such as the Central Arizona Project's supply, which provides over 30% of Arizona's water. Under this compact, the lower basin states committed to conserving more than 3.2 million acre-feet across 2027 and 2028.

Nevada initiated its legal action on August 24, just three days after the Bureau of Reclamation announced its plan, which included an annual cut of 210,000 acre-feet for Nevada. This reduction represents approximately 71% of Nevada's 300,000 acre-foot entitlement. Nevada's lawsuit alleges that the federal plan violates several key statutes, including the Administrative Procedure Act, the National Environmental Policy Act, and the foundational Law of the River. The state seeks a judicial order to halt the plan's implementation and to vacate both the operating plan and the environmental impact statement that authorized it. Arizona officials, including Department of Water Resources Director Tom Buschatzke, emphasized that intervening in the Nevada lawsuit is crucial for Arizona to protect its legal rights to Colorado River water while simultaneously maintaining avenues for collaborative solutions with California and Nevada. Governor Hobbs further indicated that Arizona intends to challenge specific elements of the final environmental impact statement and record of decision, arguing they unlawfully fail to mandate accountability for upper basin reservoirs.

The ongoing legal challenge, with Arizona joining Nevada Colorado River lawsuit, carries significant implications for water management and resource allocation across the American Southwest. For Arizona, the substantial cuts, totaling over 1.8 million acre-feet by 2028, pose a direct threat to critical water infrastructure like the Central Arizona Project, which is vital for the state's agricultural and urban needs. Similarly, Nevada's allocation, though a smaller percentage of the overall lower basin share at 3.3%, is indispensable, supplying 90% of the water used in the Las Vegas Valley. Without this supply, the already arid state faces severe consequences.

This litigation underscores a broader challenge to federal resource management decisions and the interpretation of the complex "Law of the River." The lawsuit's outcome could establish precedents for how federal agencies, particularly the Bureau of Reclamation, manage interstate water disputes and enforce obligations under long-standing agreements. Lawyers advising clients in the Lower Basin states on water rights, real estate, or agricultural operations should closely monitor the progress of this lawsuit, as its outcome could significantly alter future Colorado River water allocations and compliance requirements. It also highlights potential administrative law challenges to federal resource management decisions, emphasizing the need for careful consideration of statutory compliance in such actions.

Lawyers advising clients in the Lower Basin states (Arizona, Nevada, California) on water rights, real estate, or agricultural operations should closely monitor the progress of this lawsuit, as its outcome could significantly alter future Colorado River water allocations and compliance requirements. It also highlights potential administrative law challenges to federal resource management decisions.

Source: Original reporting via Associated Press and Courthouse News