A Century Ago, This Water Agreement Changed the West. And Now?

Reader Dan – On Water – Angry Bear

According to a University of Arizona researcher, “society is losing $2.4 billion per year because the Colorado River’s water” no longer flows all the way to the Gulf of California.


And that problem, still exists today as states argue about Colorado River water rights and keep on building inefficient new communities. It is all about the politics of growth and the water to sustain it.

A Century Ago, This Water Agreement Changed the West. Now, the Region Is in Crisis | Smithsonian Magazine, Margaret Osborne.

In the early 1920s, states in the Colorado River Basin grew concerned about their shares of water in the river. California was growing rapidly, and some feared it would establish priority access to the water.

Delph Carpenter, an attorney in Colorado, proposed that the states should come together to negotiate river water allocation. The states took 11 months to reach an agreement: the Colorado River Compact. It divided states in the watershed into an Upper Basin and a Lower Basin, which would each receive 7.5 million acre-feet of water per year. From there, the basins were left to figure out how to split up the water among themselves. 

In the decades following the compact, subsequent court cases, treaties and agreements hammered out exactly how the water would be distributed. Together, these are called the “Law of the River.”

Who was involved, and who was not?

The compact was signed by delegates from seven states—Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming—as well as a representative from the federal government, Secretary of Commerce Herbert Hoover. It was the first time so many states had come together to make an agreement—a momentous occasion in U.S. history. 

While Native Americans had been using water in the river for millennia and had legal rights to it, a 1908 Supreme Court case, decided they were to be left out of the agreement as well as Mexico.

All states ratified the compact except for Arizona. Its then-governor said the compact put Arizona at a disadvantage, because it would be forced to compete directly with California for water. Arizona later joined the agreement in the early 1940s, and the two states still face bitter disputes over water today.

One century later, what has changed?

While the Law of the River still governs water use, conditions have shifted drastically in the 100 years since the compact was signed. Hoover predicted the basin’s population, which was about 457,000 in 1915, would quadruple. Today, the river serves 40 million people—more than 20 times his prediction. 

And states are now using more water than is sustainable. The 1922 negotiations allocated water use based on data from an unusually wet period in history, Brad Udall, a senior water and climate research scientist at the Colorado Water Institute at Colorado State University, tells Smithsonian magazine. Now, with reduced water in the river and its reservoirs, these allocations are outdated. The signers likely knew their agreement would create a long-term problem, some experts say. They still ignored the research and forged ahead anyway. Brad Udall . . .

“Uses are somewhere on the order of about 15 million acre-feet. The historical flow since 2000 is around 12 million acre-feet. We’ve got a 3-million-acre-foot imbalance.”

Meanwhile, climate change is reducing the mountain snowpack that feeds the river, and it’s also causing more evaporation. Warmer, drier conditions have thrown the entire basin into a 23-year-long drought  that is ongoing. But Udall and other scientists argue the word “aridification” is a more accurate term, since the conditions are unlikely to change.

“Since 2000, the basin has been in a state of profound imbalance. As a result, the Colorado River reservoirs, the nation’s two largest reservoirs, have declined by roughly 70 percent.” 

The water shortage has forced the federal government to take drastic action—it has ordered cuts to water usage and reduced downstream releases from the Glen Canyon and Hoover dams, which form Lake Powell and Lake Mead, respectively. But even these measures haven’t been enough.

Native American tribes, which were excluded from the original 20th-century negotiations, have inherent rights to the diminishing water supply—a combined total of about 20 percent of the river’s historical flow. But many tribes are still fighting for these rights to be recognized. Tulley-Cordova says . . .

“While people are conserving, we’re trying to develop our water, a large population of our nation still don’t have running water.”

Jack Schmidt, director of the Center for Colorado River Studies at Utah State University, tells Smithsonian  magazine the situation is dire. One more extremely dry winter on a par with the record-breaking dry conditions that occurred in 2002, it will either drain Lake Powell or force the government to take unprecedented emergency action, he says.

“We’re in abject crisis right now. We’re on the edge of that cliff. We’re about to fall off.”

What’s next for the basin?

The basin faces an immediate crisis of dry conditions this winter. But it also faces the long-term crisis of overuse, says Schmidt. Adding . . .

“We must, as a nation, reduce our long-term use rates to be consistent with the supply. That’s just basic checkbook accounting.”

In 2026, several current agreements regarding water usage will expire, forcing new compromises to be made about water allocation. So far, though, no one has decided what those new rules will look like. Udall . . .

“I don’t know where we’re going. I don’t know that anybody would tell you where we’re going. But if we don’t make decisions fast, nature’s going to make them for us. The real threat here is that we empty these two reservoirs and then become reliant on an annual allocation that nature provides, instead of an annual allocation that we humans decide what’s best for us.” 

But Udall believes one reason to remain optimistic is the relationships between states and entities in the basin are good. And moving forward, Tulley-Cordova says that continuing to forge these relationships will be key. She adds . . .

“It’s not to say that we all agree on the way things should be done. But the best [strategy for] talking about a complicated subject is not assuming what the other person’s priorities, needs, and challenges and opportunities are.” 

Still, scientists say action must be taken and soon. With Lake Mead and Lake Powell at historic lows and the states failing to cut back their water use, it’s only a matter of time before nature forces the states to make uncomfortable decisions.