A Song of Water and Governance
Centuries of negotiations, broken commitments, and untenable demand along the Colorado River
When many of us think of the Colorado River, we probably think of the Grand Canyon, the Hoover Dam, the many gorgeous national parks through which it runs, or (most likely) the backdrop of several scenes in the 1994 thriller The River Wild, starring Meryl Streep and Kevin Bacon.
Beyond these idyllic nature scenes, however, we might also find ourselves thinking about massively growing populations in urban areas like Las Vegas and Phoenix — and perhaps having discordant images of green lawns and golf courses cropping up in an otherwise dry desert. The historians among us might even recall that the scarce water in this arid region has been under intense negotiation for centuries, beginning formally with treaties between the US government and the Navajo Nation Tribes in the 1800s over governance and water rights.
This year, all of these elements are coming to a head. Beneath the growing demands for water in the region and the competing claims over who gets that water sits a ticking time bomb: the expiration at the end of 2026 of a series of crucial agreements about how to manage the water of the Colorado River. But that challenge also presents an opportunity: by becoming educated, we can help make decisions that shape the future for the better.
A game of water
For millennia, Native people were stewards of the scarce water in the (now) American Southwest. Beginning in the late 1500s and 1600s, explorers from Spain arrived in the region. The first recorded water rights were established in 1852 by descendants of those explorers who were, by then, farmers and ranchers. They developed acequias, which are hand-dug ditches that served as a community-managed irrigation system, including the (still operating!) San Luis People’s Ditch.
But, as English-speaking settlers encroached on the region in the 1800s, they brought with them more demands on the water, and more tensions over the rights to it. By the time the US claimed the territory in 1848, most of the existing systems developed by Spanish settlers had been dismantled, and though the US government had guaranteed water rights to Navajo tribes in the 1800s, by the turn of the 20th century there was still no resolution of either how much water would be allocated to the tribes or how water would be divided up among the seven US states in the region (Colorado, Utah, New Mexico, Wyoming, Arizona, Nevada, and California).
Finally, in 1922, these seven states, under the direction of Secretary of Commerce Herbert Hoover, formed the Colorado River Compact. In an effort to overcome some of the disagreements between the states, Hoover made the decision to divide the Colorado River Basin (the area that drains into the Colorado River and includes the seven states and Native American lands) into an upper basin (most of Colorado, Utah, New Mexico, and Wyoming) and a lower basin (most of Arizona, Nevada, and California).
Under this compact, each of the basins was entitled to 7.5 million acre-feet of water per year in perpetuity, for a total of 15 million acre-feet. (An acre-foot is the amount of water, roughly 326,000 gallons, that it would take to cover one acre of land with one foot of water.) A number of additional contracts were added over the years, most notably a 1944 treaty that guaranteed that the two Mexican states also in the Colorado River Basin (Baja California and Sonora) would together receive 1.5 million acre-feet per year, bringing the total amount of water to be divided up each year to 16.5 million acre-feet.
At this point, you might be thinking, “Where did they get these numbers?” And, “What about the tribal nations?” I’m so glad you asked — in fact, both of these questions are at the root of much trouble to come in the region.
The Colorado River Basin includes seven US states and two Mexican states, and is home to 30 federally recognized tribal nations
Most of Wyoming, Utah, Colorado, and New Mexico make up the Upper Basin, and most of Nevada, Arizona, and California, constitute the Lower Basin. The two Mexican states are Baja California and Sonora. The tribal nations are distributed throughout the region.
A clash of science and government
While this 1922 “Law of the River” was considered a milestone at the time and led to the construction of massive water infrastructure, including the Hoover Dam and the Glen Canyon Dam (which created Lakes Mead and Powell, respectively), many of the compact’s terms were doomed from the start.
The most damning (pun intended) problem was a result of the classic and perhaps all-American tendency to ignore prevailing science. At the time of the agreement, many scientists — including hydrologist Eugene Clyde La Rue, who spent years collecting data on the Colorado River and its tributaries — estimated the annual water flow to be about 15 million acre-feet per year. Despite this, the 1922 compact was based on a much higher assumed annual water flow of between 18 and 20 million acre-feet per year.
The allocation of 7.5 million acre-feet of water per year to each of the two basins was also relatively arbitrary. Hoover came to that number because it was a midway point between competing proposals of 8.2 million by the federal government and 6.5 million by Upper Basin commissioners. Thus, between the not particularly scientific allocation of 15 million acre-feet across the basins, the addition of 1.5 million for Mexico a few decades later, and the fact that the compact didn’t take into account that about 1.3 million acre-feet would evaporate each year, this agreement was set up for problems out of the gate (literally).
A storm of unusually wet conditions
Not only was the prevailing science ignored, but it even turned out to be optimistic. Looking back, we now know that the compact was negotiated during an unusually wet period for the region. Using tree rings to estimate historical data, scientists are now fairly certain that the water levels in the river are both typically lower than they were when the compact was signed in 1922, and highly variable year to year. Indeed, it’s common to see years when river flow is not just below the optimistic original estimate of 20 million acre-feet per year, but even below the more conservative scientific calculations of 15 million acre-feet per year.
The Colorado River Compact allocated water according to unrealistically high estimates of water flow in the Colorado River
Annual water-year (October–September) reconstructed and observed streamflow in millions of acre-feet on the Colorado River at Lees Ferry, AZ, between 1800 and 2005.
A third problem is that for the past two decades, the Colorado River Basin has been experiencing a drought so severe it has now been promoted to “megadrought” status, which refers to droughts that span multiple decades. While a recent tree-ring analysis combined with machine learning algorithms estimates there was possibly an even more severe drought in the region around the first century, the current drought is largely considered to be one of the most severe in 2000 years. Much research suggests it is at least partly due to human activities, although this is hotly (another intended pun) disputed.
The image below shows just one visible ramification of this megadrought. Photographed through NASA’s Landsat satellite program over decades, the shrinking size of Lake Powell is stunningly clear.
Lake Powell’s water level and surface area have decreased considerably since 1999
Natural-color images taken by the Landsat satellites in 1999 and 2021.
A feast for no one
The effects of the reservoirs’ shrinking extend beyond alarming photos. Between 35 million and 40 million people in the American Southwest and northern Mexico depend on the Colorado River for water and hydropower (and of course it’s also a habitat for fish and other wildlife). Due to the problems described above (the disregard of science, an unusually wet period during the compact construction, and the current megadrought), the elevations, or “water fills,” of Lakes Mead and Powell are now dangerously low. Specifically, observers fear that the water levels in these two reservoirs are nearing “minimum power pool,” the lowest level that can generate hydroelectric power. Eventually they may reach “dead pool,” which is when the level is so low that water no longer flows out of the reservoir.
The graph below shows water levels in Lake Powell since it was created in 1963. Note that it took 17 years to fully fill the reservoir (a level known as “full pool”), meaning that this year’s numbers are officially the lowest on record since it reached capacity.
The water levels in Lake Powell are at their lowest since it reached “full pool”
Annual mean pool-elevation levels, in feet above sea level, for Lake Powell since filling began in 1963.
So far, we’ve seen that the seven US states that make up the Colorado River Basin struggled to put a plan in place to manage this shared resource, and that the original 1922 plan they put in place was ill suited to the region. Exacerbating all of this, of course, was the ongoing settlement of the Southwest and the resulting population boom. Nearly 80% of the water in this region is used for agriculture, with 56% used to grow livestock feed such as alfalfa, hay, and corn and 24% going to other crops. The remaining water, approximately 20%, goes to residential (12%), commercial (4%), and thermoelectric (4%) use, though these numbers may change with the recent growth in the region of data centers, which use vast amounts of water.
A dance with the federal government
This brings us back to the present. The original 1922 compact, as well as the various revisions and additions since, will expire at the end of 2026. The countdown is on for states to negotiate a new deal to manage these growing problems. And, unfortunately, they haven’t made much headway so far.
The primary problem is that the Upper Basin’s concerns are at odds with those of the Lower Basin. Very broadly, the Upper Basin states think the new contract needs to account for the fact that the environment is now fundamentally different, there is less water, and thus Lake Powell (most of which is in southern Utah) should be expected to release less water lest its elevation decline to power pool or dead pool levels.
The Lower Basin states, on the other hand, are home to many large and growing population centers, including Phoenix, Las Vegas, and Los Angeles, among others. These states argue that stability and predictability of water flow are paramount. They want all seven states to share equally in efforts to reduce water consumption, which would mean, for example, that all states cut water usage during extreme shortages. The Upper Basin states, however, contend that they already use much less water than the Lower Basin and thus should not have to cut consumption further.
Finally, the 30 federally recognized Native American tribes in the Colorado River Basin are also at the negotiating table this time around. They argue that many of the water rights they were initially promised in 19th century treaties never materialized. In fact, throughout all the negotiations, from 1922 onward, the tribes have been working to guarantee their own water rights. They experienced a setback in 2023, when the Supreme Court ruled against the Navajo nation’s claim that the federal government needs to help it build pipelines and other water infrastructure, though a new proposed settlement is making its way through Congress.
Much as with my own typical handling of deadlines, the various parties are well past several dates that were put in place for them to replace the soon-expiring agreements. They could not come to an agreement in time for a November federal deadline, and further negotiations in December also ended in stalemate. Now, these seven states, Mexico, and the 30 tribal governments have until February to propose a plan to the US Department of the Interior, which is overseeing the process.
In the meantime, on January 9 of this year, the federal government released a draft proposal outlining five possible pathways for the states. One is to “do nothing” (i.e., maintain the status quo). The others include requiring new thresholds for releasing water from dams or declaring shortages, adjusting requirements for enacting proactive conservation methods , and implementing adaptive water flows based on rainfall and snowpack in the Colorado River Basin.
The winds of a resolution?
The federal government’s draft proposal officially opened for public comment on Friday, January 16 (get involved!), and there will be two (again, open to the public!) virtual information sessions as well. Despite the complications, resource constraints, growing demands, and competing interests across the basin, some encouraging news is that this time around scientists seem to be taken more seriously, and the leaders of tribal nations are also getting more of a say. In fact, scientists are increasingly recognizing that tribal conservation methods, developed over millennia, just might hold important secrets for managing this scarce resource in this complex, arid region.
I’m not known for my optimism, and certainly not these days, but there is a version of the world where, with enough involvement and advocacy, we could see real progress toward conservation that includes everyone. I encourage anyone reading this to peruse the draft proposal (or at least the executive summary!) and join the virtual public meetings as this process of resolving a very thorny issue unfolds in real time.
 | A guest post by
|
I live in Utah and have never heard anyone thread the needle on this topic quite like you have. I now have a better understanding of the precarious situation we are in, and can participate in the discussion in a more meaningful way. Thank you!
Such an informative article. Thank you so much for taking the time to research and write this. We lived in the Phoenix area for over 28 years and water usage was always a problem.