Former CAP board president: Colorado River shortfalls will force tougher choices on farming and growth

Grady Gamage, a former president of the Central Arizona Project (CAP) board, said Arizona has historically been a national leader in water management but now faces hard trade-offs as Colorado River supplies tighten.

"For the urban spine core of Arizona, we have about 10 years worth of water total," Gamage said, adding that the years when the state could reliably bank extra water are largely over. He said most large cities in the Phoenix metro have diversified portfolios and are not likely to see taps go dry immediately, but that the state will need to make "much tougher choices" about how water is used.

Why it matters: The Colorado River is historically overallocated, and with the river delivering less water, decisions about whether to prioritize cities, manufacturing, data centers or irrigation will have concrete winners and losers. Gamage said roughly 70% of Arizona's water still goes to agriculture, and sustaining that level of irrigation along the river may no longer be feasible.

Gamage described the legal and political options available if disputes deepen. He said the Central Arizona Project could litigate in federal court and that states can bring original-jurisdiction suits to the U.S. Supreme Court — a process that would appoint a special master to take evidence. "If the Central Arizona Project, for example, could sue, they would have to sue in federal district court," he said. CAP, he added, has set aside significant funds to litigate if necessary.

At the same time, Gamage said the federal government has offered hundreds of millions of dollars to help mitigate shortages, but political dynamics complicate taking that money. He quoted Sen. Mike Lee as saying, "Well, if any of the states sue, I'm going to object and we're going to withhold that money," a stance Gamage said could coerce states away from litigation.

Given those pressures, Gamage predicted a near-term deal that "kicks the can down the road" for a few years is the likeliest outcome: federal money used to compensate farmers for reduced diversions and short-term agreements that delay a permanent resolution.

Gamage also called out high-water-use activities that cities must reassess. He said data centers use a disproportionate amount of water for relatively few jobs and have become part of a broader local debate about what uses communities should encourage. "You're not going to have any data centers in Cave Creek," he said, advising the town that its low-density desert lifestyle is more consistent with water-conservative land use.

On growth, Gamage said Arizona has shifted away from measuring success by housing starts toward prioritizing job quality and location, and that Phoenix will need to increase density over time to use water and transit infrastructure more efficiently.

The interview concluded with Royer thanking Gamage for his perspective. The immediate next steps, Gamage said, are negotiations among the basin states and federal officials; any near-term agreement will likely be temporary and depend on both political will and available federal funding.