- Arizona water leaders say federal proposals could unfairly reduce the state’s Colorado River supply.
- A coalition of 22 Arizona cities, utilities, and businesses joined the comments submitted on March 2, 2026.
- Local leaders warn that deep cuts to Central Arizona Project water could harm cities, tribes, farms, and industry.
- Arizona officials say future river rules must comply with the Colorado River Compact and share shortages among all basin states.
Thursday, March 12, 2026 — Arizona water leaders are raising strong concerns about a federal proposal that could reshape how the Colorado River is managed after 2026.
On March 2, 2026, the Central Arizona Project
submitted detailed comments to the United States Department of the Interior regarding a Draft Environmental Impact Statement that outlines possible operating rules for Lake Mead and Lake Powell after the current guidelines expire.
The comments were submitted on behalf of the Central Arizona Project and were supported by 22 Arizona cities, water providers, and organizations that depend on Colorado River water.
Those communities include major cities such as Mesa, Chandler, Glendale, Scottsdale, and Tucson, along with several towns, water companies, irrigation districts, and business organizations that rely on Central Arizona Project deliveries.
Officials said the proposal could place a disproportionate burden on Arizona water users.
Why the Central Arizona Project Matters.
The Central Arizona Project delivers Colorado River water hundreds of miles across the state through a canal system that serves much of central and southern Arizona.
According to the comments submitted to federal officials, the system helps supply water to about six million residents, tribal communities, farms, and key industries.
Those industries include advanced manufacturing, semiconductor production, agriculture, and mineral processing. State leaders say reliable Colorado River water has helped support decades of growth in Arizona’s desert communities.
Arizona Says It Has Already Cut Water Use.
Arizona officials argue that the state has already made significant sacrifices to stabilize the river.
In recent years, Arizona and other Lower Basin states have reduced water use to protect Lake Mead and Lake Powell as the river system faces long-term drought and declining flows.
Arizona representatives say those reductions total about 8.9 million acre-feet of water.
State officials say Arizona has also offered to conserve even more water if reductions are shared across the entire Colorado River Basin.
Key Legal Concerns Raised in the Comments.
In its comments to federal officials, the Central Arizona Project argued that the draft plan contains several serious legal and technical problems.
One major concern involves the Colorado River Compact of 1922, the agreement that divides river water between the Upper Basin states and the Lower Basin states.
Arizona officials say the draft proposal does not properly analyze whether future river operations would comply with the compact’s delivery requirements.
The comments state that failing to address those obligations could risk a future “compact call,” which occurs if the Upper Basin does not deliver the amount of water required to the Lower Basin over a ten-year period.
The document also argues that federal modeling used in the proposal assumes large increases in water use in the Upper Basin while at the same time placing most shortage impacts on Arizona.
Arizona officials say that imbalance could violate long-standing agreements known collectively as the “Law of the River,” which governs Colorado River operations.
Potential Economic Impacts.
The comments warn that deep reductions in Central Arizona Project deliveries could have far-reaching consequences.
Modeling cited in the comments suggests that some proposed scenarios could reduce deliveries through the system to roughly 237,000 acre-feet per year.
Officials say shortages at that level could affect water providers, farms, businesses, and tribal water settlements across the state.
The report also notes that water providers might have to rely more heavily on groundwater and stored water supplies to replace lost river deliveries. Over time, those backup supplies could become difficult to maintain.
Video:
Local Communities Highlight Water Conservation.
At the same time, local communities say they are working to stretch every drop of water they receive.
In a video released March 9, 2026, mayors from several Arizona communities described steps their cities have taken to conserve water and manage supplies more carefully.
Cities such as Chandler report that household water use has dropped significantly over the past 25 years, while other communities have developed reclaimed water systems, conservation programs, and long-term water plans.
Leaders from Florence, Goodyear, Oro Valley, Coolidge, and Glendale said the Colorado River remains a vital lifeline for homes, businesses, agriculture, and future economic growth.
Call for a New Approach.
Arizona officials say they remain willing to work with other states and the federal government to reach a shared solution.
However, they argue that the current draft environmental study should be withdrawn and revised before final operating rules are adopted.
Central Arizona Project leaders say future river management must comply with the Colorado River Compact, the broader Law of the River, and the federal environmental review process.
They also say long-term solutions must involve shared responsibility among all seven Colorado River Basin states.
As negotiations continue, the debate highlights the difficult choices facing the region as the Colorado River system adjusts to a drier future.
