From California to Nebraska, the western US is grappling with a water crisis. An ongoing drought is predicted to last until at least July 2022. Recent research suggests that these conditions may be better labeled aridification – meaning that warming and drying are long-term trends.
On the Colorado River, the nation’s two largest reservoirs – Lake Powell and Lake Mead – are at their lowest levels in 50 years. This could threaten the water supply for western states and power generation from large-scale hydroelectric turbines embedded in lake dams. In August 2021 the federal government issued the first ever water scarcity announcement for Colorado, leading to supply cuts in several states.
Seven Colorado River Basin states – Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming – signed a water-sharing agreement, the Colorado River Compact, in 1922. Some observers are now calling for the compact to be renegotiated to correct errors and oversights. , Nebraska and Colorado are also debating the waters of the South Platte River, which they share under a separate agreement signed in 1923.

Colorado State University Water Resources Archive, CC BY-ND
My work as the head archivist of Colorado State University’s Water Resources Archive gives me a unique perspective on these struggles. Our collection includes the papers of Delph Carpenter, an attorney who developed the concept of the Interstate River Compact and negotiated both the Colorado and South Platt Agreements.
Carpenter’s drafts, letters, research and reports show that he believed the compact would reduce litigation, preserve state autonomy and promote the common good. In fact, many states now use them. Looking back at Carpenter’s documents, we can see that the Interstate River Compacts were an innovative solution 100 years ago – but were written for the West very differently than they are today.
water for growth
In the early 1900s, there was a lot of water to go around. But there weren’t enough dams, canals or pipelines to store, move or use it. Devastating floods in California and Arizona led to plans to build dams to stop the high river flow.
With the Reclamation Act of 1902, Congress directed the Interior Department to develop infrastructure in the West to supply water for irrigation. As the Reclamation Service, which later became the powerful Bureau of Reclamation, progressed, it began planning dams that could also generate hydroelectricity. Low-cost electricity and irrigation water will become important drivers of development in the West.
Carpenter was concerned that the downstream states, building dams for their own needs, would demand water from the upstream states. He was particularly concerned with the issue as a native of mountainous Colorado, the source of four major rivers – the Platte, Arkansas, the Rio Grande, and the Colorado. Carpenter wanted to see the Upper Basin states “sufficiently protected before the construction of structures on the Lower River”.

USGS
Carpenter was also aware of interstate water conflicts. In 1916, a group of Nebraska irrigators sued farmers in Colorado for drying up the South Platte River at the state line. Carpenter was already the lead attorney for Colorado in Wyoming v. Colorado, a case involving the Laramie River that began in 1911 and would not be resolved until 1922.
Carpenter saw such legal battles as a waste of time and money. But he faced “skepticism, apathy, failure of understanding or open ridicule” when he proposed negotiations on interstate river components, he recalled in a 1934 essay.
Carpenter eventually persuaded his Colorado customers to settle their lawsuit by negotiating a compact to share water from the South Plateau with Nebraska. Data collection and discussion took seven years, but Carpenter believed the agreement would ensure “lasting peace with our neighboring state.”
Or maybe not. Today Nebraska officials are looking to revive an unfinished canal to draw water from the South Platte in Colorado, citing concerns about several of Colorado’s planned upstream water projects. Colorado officials pledging to aggressively defend their state’s water rights may take the states to court.
dividing Colorado
West of the Continental Divide, the Colorado River flows more than 1,400 miles southwest into the Gulf of California in Mexico. Once upon a time, its delta was a lush network of lagoons; Now the river ends in the desert because the states carry so much water upstream from it.

When settlers developed west, their prevailing attitude was that the water that reached the sea was wasted, so people aimed to use it. California had a larger population than the other six Colorado River Basin states, and Carpenter was concerned that California’s use of the river might hinder Colorado under the prior appropriation doctrine, which dictates that the first to use the water. The person gains the right to use it in the future. With the US Reclamation Service studying Colorado to find good dam sites, Carpenter also feared that the federal government would take control of the river’s development.
Carpenter studied international treaties as models for the River Compact. He knew that American states have the right to make agreements with each other under Article 1, Section 10 of the US Constitution. And he believed that resolving water conflicts between states required “state skills of the highest order”.
In 1920, officials agreed to try his approach. After the states and the federal government adopted legislation to authorize the process, delegates began meeting in January 1922 as the Colorado River Commission, with Secretary of Commerce Herbert Hoover as chairman. Minutes of the meeting show that negotiations almost collapsed several times, but the ultimate goal of rapid river development held them together.
The commissioners reached a settlement in 11 months, adopting the final version of the compact in November 1922. It allocated a fixed amount of water to the upper and lower basins—measured in full acre-feet, not a percentage of the river’s flow. With the fall in the water level of the river, this approach has proved to be a major challenge today.

In their meetings, the commissioners discussed both the variability of river flows and the lack of sufficient data for long-term planning. Yet in the final agreement he allowed the surplus water to be divided starting in 1963. We now know that they used optimistic flow numbers measured exclusively during wet periods.
a warmer, more crowded west
Today the West is facing conditions that Carpenter and his companions had not anticipated. In 1922, Hoover envisioned that the population of the basin, which was about 457,000 in 1915, might quadruple in the future. Today, the Colorado River supplies about 40 million people—more than 20 times Hoover’s projection.
The commissioners also did not anticipate climate change, which is making the West hot and dry and reducing the volume of the river. Some water experts say a new agreement is needed that recognizes the era of scarcity. Others say re-negotiating is politically impossible. States signed a drought contingency plan in 2019, but it only lasts until 2026.
Testifying before Congress about the Colorado River Compact in 1926, Hoover said, “If we can provide equity for the next 40 to 75 years we can count on the next generation to be as intelligent as we are today.” Will be.” Faced with extreme western water challenges, it is now up to Westerners to meet – or exceed – that expectation.
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