The Colorado River Compact of 1922 Explained

colorado river
Beth Ruggiero-York/

Written by Kristen Holder

Updated: July 21, 2023

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The Colorado River is the sole dependable water source in parts of seven states and Mexico. Because of this, it is one of the most heavily managed watercourses in the world. To understand how current water resources are allocated, the Colorado River Compact of 1922 that started it all needs to be explained.

The western United States is vast and dry. It is comprised of various arid to semi-arid environments that frequently experience profound drought. As a consequence, the reliable delivery of water is vital to the success of permanent civilization and industry in this part of the USA. 

The way America has handled water projects like the Colorado River Compact of 1922 influences how other arid countries structure their water rights. Lessons have been learned over the last century as a more comprehensive view of water rights continues to develop. Below, the Colorado River Compact of 1922 is explained in detail.

Infographic about the Colorado River.
The Colorado River runs through several states and carved the Grand Canyon.

What is the Colorado River Compact of 1922?

On November 24, 1922, in Santa Fe, NM, the Colorado River watershed that contains 7 states was divided into upper and lower sections. The Upper Basin contains Colorado, Wyoming, Utah, and New Mexico. Nevada, California, and Arizona share the lower basin.

The Colorado River Compact of 1922 is essentially a peace treaty related to water rights along the Colorado River. The Colorado River Compact of 1922 is an agreement aimed at distributing the water in the Colorado River evenly. The water rights of 244,000 square miles of land in Arizona, Colorado, Nevada, California, New Mexico, Utah, and Wyoming were addressed.

There were 3 definable phases of the negotiation process that were marked by heated struggles between the states. The final agreement restricts how much water the Upper Basin can keep for itself. This means it must send a certain amount of water downstream into the Lower Basin.

Member states of the Colorado River Compact

Member states of the Colorado River Compact include Upper Basin Colorado, Wyoming, Utah, New Mexico, and Lower Basin Nevada, California, and Arizona

Why Was the Colorado River Compact of 1922 Needed?

Since the western United States and Mexico is so arid, any uncontrolled growth without the consent and participation of all states and countries using the Colorado River leads to a disaster in resource allocation.

There simply isn’t enough water in the western United States for the majority of the land to be developed. As a result, development was deadlocked, and disagreements escalated.

The Colorado River Compact of 1922 was the first official attempt to address these issues. At this time in history, the rapid development of the western US was taking place. Something needed to be done to coordinate this development in light of guaranteed water depletion should development progress unchecked.

States were bitterly embroiled with each other, and water laws contradicted each other across state lines. Unfortunately, while the Colorado River Compact of 1922 was a step in the right direction, it just inflamed disagreements. American Indian rights were not considered, and hostilities between California and Arizona were not anticipated.

The Colorado River Compact of 1922 and the Law of the River

The 1922 Colorado River Compact is the beginning and the cornerstone of the Law of the River. The Law of the River is the comprehensive collection of laws, court decisions, compacts, and contracts that currently regulate the Colorado River.

The water amounts agreed upon in 1922 between the Upper and Lower Basin were later shown to be inaccurate and were addressed in future meetings. However, the established framework from the 1922 compact remains.

Hydroelectricity and the 1922 Colorado River Compact

A century ago, the benefits of hydroelectricity were revolutionizing American daily lives. The infrastructure needed to drive the use of electricity by both industry and municipalities needed to quickly expand to keep up with demand.

The establishment of rules around water flows in areas where dams could go set the stage for the development of a large network of hydroelectric developments. The Hoover Dam and resultant Lake Mead are examples of the type of innovations that were later achieved thanks to the framework of the 1922 Compact.

Flood control, provision of irrigation water, and producing hydroelectricity were key reasons for the construction of the Hoover Dam on the Colorado River.

Flood Control and the Colorado River Compact of 1922

The amount of water that flows through the Colorado River varies wildly by year and by season. As a result, flood control measures needed to be put into place to maximize both water use and development potential along the river.

The compact was needed so that flood control measures along the Colorado River could be put in place. Flood control of such a large river that spans such a great distance takes a coordinated effort between states. Dams were constructed not just to feed hydroelectric projects but to contain floodwaters in mass quantities for later use.

State vs. Federal Rights and the 1922 Colorado River Compact

States dependent on the Colorado River feared that fast-developing Los Angeles would use so much water that nothing would be left for outside development. This is why even quarrelsome states were willing to come to a preliminary agreement. States also needed to work together before the federal government swooped in to make decisions for them.

States fiercely protect their rights to make decisions for themselves while also seeking the support of the federal government. Programs related to railroads, dams, canals, and roads need funding from the federal government to come to fruition. However, states carefully guard their rights while infrastructure is put into place.

The cooperation shown between states was unprecedented, as only 3 states had cooperated in the past over water rights. However, Arizona refused to ratify the compact until 1944 because it believed that water should be allocated directly to the states themselves and not the newly established basins.

Colorado River at the California Arizona border

The Colorado River is one of the most heavily managed watercourses in the world as a result of the Colorado River Compact of 1922.

The Colorado River Compact of 1922 and Mexico

Mexico occupies part of the Colorado River Basin and has rights to 2,000 square miles directly affected by any Colorado River water treaty. It also controlled the water available to the Imperial Valley in the southeastern corner of California in the early 1900s.

Official agreements between Mexico and the United States didn’t occur until the Mexican Water Treaty of 1944. However, the 1922 treaty did establish a small amount of water for Mexico which set a precedent. Unfortunately, the major overestimation of water flows through the Colorado River in the 1922 compact negatively affected Mexico.

Mexico not only expected its guaranteed allotment but overflow water as well. This overflow was not enough, and the Colorado River Delta in Mexico began deteriorating. Only a fraction of the original ecosystem remains.

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About the Author

Kristen Holder is a writer at A-Z Animals primarily covering topics related to history, travel, pets, and obscure scientific issues. Kristen has been writing professionally for 3 years, and she holds a Bachelor's Degree from the University of California, Riverside, which she obtained in 2009. After living in California, Washington, and Arizona, she is now a permanent resident of Iowa. Kristen loves to dote on her 3 cats, and she spends her free time coming up with adventures that allow her to explore her new home.

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