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Opinion: Why Colorado is losing the water war

Colorado cooperates with other states to avoid a long, unpredictable Supreme Court battle. But if we cooperate and Arizona doesn’t, we may continue to lose.

The Glen Canyon Dam at Lake Powell in Page, Arizona. (Jesse Paul, The Colorado Sun)

The Colorado River is under stress today due to rising temperatures and declining streamflows, as described in a Dec. 13 Colorado Sun opinion essay by Russell George and John Stulp. The other cause, seldom mentioned, is a water war among seven states, Mexico and the federal government — a war Colorado has been losing.

The 1922 Colorado River Compact called for dividing the river’s water equally between the Upper Basin (Colorado, northwestern New Mexico, Utah, Wyoming and far northeastern Arizona) and the Lower Basin (California, Nevada, the rest of Arizona, southwestern Utah and western New Mexico). In the compact, each basin was promised 7.5 million acre-feet of water each year. (An acre-foot is 325,851 gallons, enough to cover an acre, about the size of a football field, 12 inches deep.) 

Ed Millard

At the last minute, Arizona demanded exclusive use of water from the Gila River, which flows from New Mexico across Arizona to the Colorado River at Yuma. In 1945, a treaty with Mexico further unbalanced the deal. There’s more information here.

Today, the Upper Basin states use only a quarter of the river’s water, while the Lower Basin states use more than double that. Add in Mexico, which has been allocated 1.5 million acre-feet, and the Lower Basin uses two thirds of the river. The Upper Basin, including Colorado, has already surrendered 3 million acre-feet of our compact entitlement, our water right, to the Lower Basin to deal with this over-allocation. 

Chart shows how Colorado River water is distributed. “CRSP” refers to the Colorado River Storage Project, which includes Lake Powell and other reservoirs in the upper Colorado River basin. (Graphic by Ed Millard, based on 2016 Upper Colorado River Commission data)

Now, with drought and rising temperatures, Colorado is being asked to take farms and ranches out of production, potentially turning our communities to dust, to give up the water we actually use to Lake Powell, a massive reservoir on the Colorado River where water is stored for delivery to the Lower Basin. 

Meanwhile the Lower Basin has been using all of its entitlement, while running structural water deficits that have drained Powell and Lake Mead, another Colorado River reservoir. The Lower Basin also has put unused water in aquifers, contrary to the spirit of the compact, and Arizona has gamed the rules governing Lake Powell.

When the Central Arizona Project (CAP) was authorized in 1968, diverting Colorado River water to parts of Arizona, it was known by Congress, federal officials, the Upper Colorado River Commission and the seven states that there wouldn’t be enough water in the river when the project came online. The price the Upper Basin demanded to support CAP was a guarantee that our unused entitlement to water under the Colorado River Compact would be protected for our future use. 

This guarantee was codified in federal law in 1968:

SEC. 603. (a) Rights of the upper basin to the consumptive use of water available to that basin from the Colorado [River] system under the Colorado River Compact shall not be reduced or prejudiced by any use of such water in the lower basin.

This promise is being broken.

In their opinion piece, George and Stulp say: “We are … the beneficiaries of several decades of cooperative actions to find mutually agreeable adjustments to those rules that benefit the basin as a whole.” (Emphasis mine.)

Yet one state has chosen the threat of litigation over cooperation on water multiple times over the years, such as in 2005, when it demanded that releases from Lake Powell be increased from 8.23 million acre-feet to 9 million acre-feet much of the time. 

As Arizona water officials and their attorney said in a 2007 law-review paper, increased water releases would “relieve Arizona of the need to challenge the legality of” federal rules governing releases from Lake Powell. They also warned that “Arizona reserves the right to challenge future use” of those rules.

Arizona got what it wanted. Releases of water increased to an average of 9.2 million acre feet, driving pressure to fallow our farms and ranches. There is what amounts to an open drain in Lake Powell.

Colorado cooperates with other states to avoid a long, expensive, unpredictable U.S. Supreme Court battle. But if the Upper Basin cooperates and Arizona doesn’t, we may continue to lose.

Some want to pursue one, dogmatic approach to this problem, with a name only a bureaucrat could love: Demand management, which the Colorado Water Conservation Board defines as “temporary, voluntary and compensated reductions in the consumptive use of water.” I define it as taking our farms and ranches out of production.

Upper Basin demand management is much harder than some people think. There are myriad funding, legal, engineering and policy issues that have to be resolved. The policy may be encouraging water speculation. Colorado doesn’t have money for it because of COVID impacts on the budget. The Upper Basin has been talking about it since 2010, doing expensive pilot projects since 2015, and we still haven’t saved a drop in Lake Powell.

We need to work on a host of viable solutions. Vigorous defense of our compact entitlement to water in negotiations is important, and better forest management also has to be part of the policy debate.  Forests use more than 80% of the precipitation in the Upper Basin, and they are using more as temperatures rise driving this problem.

Investing in agricultural efficiency also is critical. Canal liners and pipelines conserve water in perpetuity while increasing production.

We also need to work on desalination of water in the Lower Basin, more municipal reuse of water, and cloud seeding to produce more snowfall, among other approaches.

We look forward to working together to pursue solutions we can all live with. We face a dire scenario if we fail!


Ed Millard represents Montezuma County on the Southwest Basin Roundtable and the Roundtable on Colorado’s Interbasin Compact Committee. He notes that his comments reflect his own views and not those of these organizations. On Twitter @edmillard.


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