On its 100th birthday, the Colorado River Compact shows its age

The foundational document was flawed from the start.

A century ago this month, representatives from the seven states in the Colorado River Basin came together at Bishop’s Lodge, north of Santa Fe, and signed the Colorado River Compact. It was and still is a momentous occasion. The nation’s first interstate treaty involving more than two states brought an apparent end to acrimony and litigation between the states over who gets how much water. It formed the foundation that undergirds the “Law of the River” — which governs the Colorado River to this day. And it opened the door to damming the Colorado River to moderate its wildly fluctuating flows and curtail flooding along the lower stretches of the river.


“The big thing about the Colorado River Compact is that it breaks the blockade on development of the whole river,” wrote then-Secretary of Commerce Herbert Hoover, who oversaw the negotiations. “The worst thing about the compact is that it will destroy much oratory. It makes for growing spuds, not glowing speech.”

If Hoover were alive now, he might have second thoughts about that assessment. It would turn out that the foundation, as solid as it may have looked, was actually full of holes. Tribal nations were not only left out of the Compact and negotiations, but their senior and therefore stronger water rights were discounted altogether. This was not only legally and morally wrong, but also would create conflict down the road.

Additionally, the entire compact was based on flawed — and maybe even fabricated — assumptions, with more water allocated to the states than was actually in the river, setting the stage for demand to outpace supply. Yet the compact included no contingencies for such a scenario. The document’s framers never even considered the possibility that the river’s flows would diminish over time, as is now the case thanks to climate-change-induced aridification.

Now, the flaws are turning into fatal ones, as the states, tribal nations and federal government struggle to correct the supply-demand imbalance within the framework of the compact. And, despite what Hoover may have hoped for, that has spurred much oratory indeed, from federal officials warning of imminent “dead pool” and “system collapse” to Nevada and Arizona officials scolding California alfalfa farmers for guzzling so much water.

On the compact’s 100th birthday, we take a look back at how the agreement came about and analyze some of the most salient — and flawed — provisions in hopes of illuminating this revered and sometimes reviled document. 

Black Canyon on the Boulder River in Colorado before work started on the construction of the Boulder Dam (now renamed Hoover Dam).
General Photographic Agency/Getty Images

Why form a Colorado River Compact?

In the early 1900s, California was quicker than its neighbors to put Colorado River water to “beneficial uses” like irrigation. That made the slower-growing upstream states anxious: Under the law of prior appropriation, the first to use the water gets to keep using it, meaning California users potentially could guzzle up senior water rights and force other states to turn off their spigots in times of shortage. This possibility was affirmed by the U.S. Supreme Court’s 1922 decision in Wyoming v. Colorado, which held that “waters of an innavigable stream rising in one state and flowing into a state adjoining may not be disposed of by the upper state as she may choose.”

Anxiety led to litigation and conflict, which in turn complicated plans to dam the Colorado River to even out its wild fluctuations and subdue the “menace” of floods in its lower reaches. In January 1922, representatives from the seven states and the federal government began negotiating an agreement.

“The purpose of the Compact,” notes its appended introduction, “was to put an end to the litigation which has held up the development of the river for many years … A physical problem of this character can not be dealt with on legalistic principles, but must be settled on physical and engineering grounds.”

President Herbert Hoover and representatives from seven Western states sign the Colorado River Compact in 1922 near Santa Fe, New Mexico. The compact allocated the amount of Colorado River water that Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming could legally use for water supply.
U.S. Department of Interior, Bureau of Reclamation.

The introduction goes on to say that the compact would facilitate or open the door to:

  • “Orderly development through irrigation and cultivation of 4 million acres of land, now desert.”

  • “Construction of dams urgently needed for control of floods annually, threatening Imperial and Palo Verde Valleys in California and Yuma project in Arizona—rich communities assessed at over $1 million where 45,000 to 100,000 Americans gain their living.”

  • “New homes for 3 million American citizens, including ex-service men and women.”

  • “New communities which will furnish increased markets for the whole country.”

  • “Increased wealth to meet our tax burden.”

What the compact does

It divides the nearly 250,000-square-mile watershed into an upper and a lower basin. The dividing line is Lee’s (aka Lee or Lees) Ferry, in northern Arizona below the confluence of the Pariah and Colorado Rivers. The Upper Basin comprises Wyoming, Colorado, Utah and New Mexico, while the lower includes California, Arizona and Nevada. The two basins are “separated by 1,000 miles of canyons and different agriculture and economics,” notes Hoover in his commentary, so “the logical thing is to divide the water between them so they can make homes instead of defend injunctions.” 

Each basin is given in perpetuity the exclusive use of 7.5 million acre-feet of water per year, “which shall include all water necessary for the supply of any rights which may now exist.” The Lower Basin gets the right to an additional 1 million acre-feet. Mexico’s share — later determined to be 1.5 million acre-feet — would come out of any surplus or be borne equally by the two basins.

The compact also creates a pecking order of uses, with agriculture and domestic uses taking priority over power production.

To ensure the Lower Basin would get its share, another provision mandated that the Upper Basin “not cause the flow of the river at Lee Ferry to be depleted below an aggregate of 75 million acre-feet” for any 10-year period.

The original compact did not divvy up each basin’s share between the states. That was left to the states to tussle over, basing the allocations on existing water rights, the amount of irrigable acreage in each state and that state’s political heft.

The compact also creates a pecking order of uses, with agriculture and domestic uses taking priority over power production. Navigation is last in line. Neither wildlife nor recreation are mentioned in the compact or accompanying commentary.

Fatal flaw #1

There are 30 tribal nations within the Colorado River watershed and yet not one was included in the negotiations nor even consulted during the creation of the compact. That’s in spite of the fact that tribes are sovereign entities with rights superior to state governments. The exclusion was far worse than a gross oversight; it was a blatant attack on tribal sovereignty.

It also showed an egregious lack of foresight. Fourteen years before the compact was ratified, the Supreme Court’s ruling in Winters v. the United States established that when the federal government “reserved” land for a tribal nation, it also reserved rights to water. And the appropriation date for those water rights would be the date the reservation was established, whether or not the tribe put the water to “beneficial use” at that time. Winters did not quantify the amount of water tribes were entitled to, except that it should be “sufficient … for irrigation purposes.” 

This positioned the tribes as some of the most senior — and largest — water rights holders in the Colorado River Basin. By leaving the tribes out of the process, the framers set the stage for conflict down the road, when the tribes quantified and settled their water rights with the federal government. (Tribal rights are not subject to state water laws.)

The compact’s sole acknowledgment that the tribes even existed was a single sentence, which read: “Nothing in this compact shall be construed as affecting the obligations of the United States of America to Indian tribes.” And since the compact divvied up all of the water in the Colorado River Basin — and then some — between the seven states, tribal water rights would be counted against the respective states’ shares.

This was confirmed by the Supreme Court’s 1963 Arizona v. California ruling, which quantified federal reserved water rights for five lower Colorado River tribal nations, amounting to 900,000 acre-feet between them, which was included as part of Arizona’s 2.8 million acre-feet share. Thus far, tribes in the Lower Basin have quantified and settled a little more than 2 million acre-feet, while Upper Basin tribes have together settled 1.1 million acre-feet, and rights remain unquantified and unresolved for a dozen additional tribes. For example, the Winters doctrine entitles the Navajo Nation to 5 million acre-feet or more with an 1868 appropriation date, but so far the federal government has only quantified and resolved a small portion of that. Even as the Colorado River’s collective users must together cut 2 million to 4 million acre-feet of consumption, they will also have to find enough additional water to honor those unresolved rights.

The exclusion was far worse than a gross oversight; it was a blatant attack on tribal sovereignty.

Fatal flaw #2

An introduction to the compact notes that the agreement “allocates in perpetuity 16 million acre-feet, or 80 percent of the total natural flow of 20 million acre-feet of the river, more than sufficient to water all lands now being irrigated and all lands which can be economically developed for forty years to come.”

This one has come back to bite the Colorado River’s users in the butt, big time. Even back then there wasn’t anywhere near 20 million acre-feet of water in the river most of the time — and the signatories knew that. Over a nine-year period preceding the ratification, the U.S. Geological Survey recorded an average annual discharge of about 17.3 million acre-feet at a point just upstream from the U.S.-Mexico border, with yearly flows ranging from 9.9 million acre-feet to 26.1 million acre-feet. That was during an unusually wet period.

And in 1916, Eugene C. LaRue — one of his era’s foremost authorities on the Colorado River — compiled an extensive report on the river and its tributaries for the USGS. His research included envy-inducing trips down the Colorado River through stretches that have since been inundated by dams. He wrote that discharge data “indicate that complete utilization and control of the stream waters in the upper basin will create a shortage of about 3.8 million acre feet in the supply available for the lower basin. More complete data would probably indicate a greater shortage in the water supply available … Evidently, the flow of the Colorado River and its tributaries is not sufficient to irrigate all the irrigable lands lying within the basin.” 

Boulder Dam (renamed Hoover Dam), 1941.
Ansel Adams / Department of the Interior

LaRue also warned against building Hoover Dam because evaporation would further deplete water supplies — though he was a proponent of Glen Canyon and other dams — and suggested banning trans-basin diversions, or exporting water from the Colorado River watershed to other parts of the seven basin states. The signatories heard LaRue but clearly didn’t heed his warning, even though he repeated it many times prior to the compact’s signing. (He eventually resigned in protest.) Whether the numbers that ended up in the compact were merely wishful thinking or deliberate fraud is an open question. 

Just a decade after the compact was signed, LaRue’s prognostications were proved correct when a prolonged drought settled over the region. And beginning in the 1940s, tree-ring investigations showed the river historically carried less than 14 million acre-feet per year — or 30% less than the amount on which the compact was based. In other words, a 2 million acre-feet shortage was baked into the compact — a shortage that has only grown since the late 1990s, when the longest stretch of dry years in over a millennium began 

What’s next?

Despite its flaws, the Colorado River Compact was a powerful and effective document when it was ratified — for the parties included in the negotiations, that is. It eased the acrimony between the states (although Arizona refused to ratify the compact for decades due to disagreements with California). And it equitably divided the Southwest’s largest river between the two basins.

But it hasn’t aged well. Those same flaws have become more and more pronounced, as demand on the Colorado River’s waters continues to grow while the supply dwindles. And just as the compact once spawned amity, it is now spurring conflict and tension.

Thus far, efforts to right the supply-demand imbalance have proceeded within the terms of the compact. But the fact that necessary cuts in consumption are slow to be realized is evidence that the compact is sinking deeper into obsolescence. Now that it’s reaching its centennial, perhaps it’s time for the Colorado River Compact to retire, and for the river’s users — all of them — to sit down and negotiate a new pact for a changing world.

“Nor can one make great oratory out of the fact that there is ample water and to spare after the apportionment of enough water to each basin in perpetuity to cover all of the present uses plus all of the known feasible projects, plus 20 percent for good measure,” wrote Hoover 100 years ago this month, in what may have been one of the most ignorantly optimistic, and least sagacious, statements regarding the compact. “Yet, behind all the precise and commonplace language of the compact lies the greatness and romance of the West, the building of a million more homes out under the blue sky in security and good will.”

Oh, how wrong he was.

The Colorado River seen flowing through the Grand Canyon.
Alex Demas/USGS

Jonathan Thompson is a contributing editor at 
High Country News. He is the author of Sagebrush Empire: How a Remote Utah County Became the Battlefront of American Public Lands. 

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