The Arizona Department of Water Resources has formally rejected key elements of the federal government’s 10-year strategy for managing shrinking Colorado River reservoirs, warning that the plan could lead to catastrophic reductions in the water the state is entitled to receive and that Arizona may pursue legal action.
State objects to federal discretion over deep cuts
In a sharply worded letter to federal officials, Arizona water leaders said the plan gives the federal government wide latitude to choose from a range of options — including very large reductions in deliveries — on a recurring basis. The letter argues that approach conflicts with the allocations established by the 1922 Colorado River Compact and the broader legal framework known as the "Law of the River."
"Arizona does not accept a framework that gives the federal government the discretion to select from a wide range of alternatives — including catastrophic cuts … every two years for the next decade," wrote Tom Buschatzke, director of the Arizona Department of Water Resources.
The federal proposal, released July 31, allows for steep cuts if officials determine they are necessary to protect system reservoirs, potentially reducing combined deliveries to the three lower-basin states — Arizona, Nevada and California — by as much as 3 million acre-feet per year, roughly 40% of their combined allotments, under the most severe scenarios.
Short-term agreement, long-term dispute
For the immediate two-year period, federal officials accepted an offer from the three lower-basin states to reduce diversions by about half of that maximum amount. Arizona’s letter makes clear, however, that state leaders do not consent to an open-ended federal authority beyond that two-year window and said the state “reserves its rights” to demand compliance with the compact and to seek relief in an "appropriate judicial forum." The letter did not specify when, or under what conditions, Arizona would file suit.
The dispute sets up the possibility of a high-stakes legal fight that could ultimately reach the U.S. Supreme Court and complicate ongoing negotiations among the seven basin states that share the river’s dwindling water and its major reservoirs, now at historically low levels.
What this could mean for Arizona
State officials say the plan as written could impose harsh shortfalls on Arizona users. Legal action would aim to restrict federal authority to impose cuts that the state views as inconsistent with long-standing interstate agreements.
- Allocation authority: Arizona disputes the federal government’s ability to select among drastic cut scenarios beyond the two-year period.
- Potential litigation: The state has reserved the right to pursue legal remedies up to and including litigation in federal courts.
- Interstate negotiations: A court battle could strain efforts by the seven basin states to craft cooperative solutions for the decade ahead.
Context and next steps
The plan is part of a federal effort to address long-term shortages driven by prolonged drought and declining reservoir storage across the Colorado River system. The lower-basin states accepted a temporary reduction proposal for the next two years, but Arizona’s letter signals a firm stance against a permanent shift in decision-making power.
Officials in Arizona will continue coordinating with stakeholders as they evaluate options. The state’s notice that it “reserves its rights” is a formal step that preserves legal arguments Arizona may use to challenge future federal actions related to river operations and allocations.
| Item | Details from federal plan |
|---|---|
| Maximum potential cuts | Up to 3 million acre-feet per year to the three lower-basin states in severe scenarios |
| Near-term agreement | Lower-basin states offered about half of that reduction for the next two years |
| Arizona’s position | Rejects framework beyond two years; reserves right to pursue judicial remedies |
How the federal government responds to Arizona’s objections will shape the next phase of basin management. If disagreements persist, the case could move into the courts, where legal interpretation of the compact and the balance between federal authority and state rights will be tested.
The trajectory of those deliberations will be watched closely by municipal water providers, agricultural users, tribal nations and others who rely on the Colorado River system for critical supplies. Any long-term shifts in allocation or operational control would have widespread consequences across the Southwest.
As discussions continue, Arizona’s formal reservation of rights marks a clear signal: the state intends to vigorously defend what its leaders say are statutory and compact-based entitlements to Colorado River water.
