Issue: Colorado River Compact

As the Central Arizona Project celebrates the 50th anniversary of the federal act that authorized the massive water project, Arizona is still locked in complicated conversations about how the state will move forward on water issues.

A half century ago, President Lyndon Johnson signed into law the Colorado River Basin Project Act, which authorized construction of CAP to funnel water from the Colorado River Basin to central Arizona.

During the signing, Johnson called the bill landmark legislation that built on a series of previous conservation measures he had signed. He also proclaimed the signing day, “Carl Hayden Day” after the Arizona senator who played an integral role in furthering the state’s water interests.

“For the millions of Americans west of the Continental Divide, it will provide more water for growing cities; it will provide more water for expanding industries, for the farmers’ crops, and for the ranchers’ cattle,” Johnson said.

But decades-old conversations about the longevity of using the Colorado River Basin as a major water source are still ongoing today as a contingent of seven Western states work to prevent water shortages into the future.

CAP, which is now a 336-mile system of channels, pipelines and pumping stations that move water, was envisioned decades before Johnson gave his approval.

Congress allocated $1.2 million for CAP construction in 1970, but the federal government didn’t release the money until after Arizona created the Central Arizona Water Conservation District. Construction of CAP started five years after the act’s signing on September 30, 1968.

CAP Deputy General Manager Tom McCann said he’s not sure anybody really knows directly where the idea for CAP came from. People had the general idea of taking water from the Colorado River and bringing it to central Arizona for the past 100 years, he said.

During the 1930s and 1940s, both business and agriculture interests were working on plans to bring water from the Colorado River to the heart of the state to spur business and farming developments.

John Harrison, CAP’s construction contract administrator, still has a copy of a CAP project planning report from 1947. He estimates there were somewhere around 20 such planning reports.

“It was actually a long time coming to be,” he said. “It was on the drawing board from the state of Arizona for I don’t know how long.”

Some refer to CAP as, “the last big one” because the federal government hasn’t taken on a water project of that magnitude since.

Passing the Colorado River Basin Act through Congress was no easy task. Multiple attempts to pass the act were torpedoed by the California congressional delegation, which didn’t want its state to face any cuts to its water.

In order to make the deal happen, Arizona agreed to take junior priority status, meaning it would be the first state to take water reductions during a shortage.

McCann called the lengthy process of getting the act passed politics as usual.

“It’s easy to ask yourself today, especially from the Arizona perspective, well, why did Arizona politicians ever go along with that? If you read the things they said at the time, it was very clear that they felt they didn’t really have any alternative,” he said.

But water discussions continue among Arizona and other Western states. Right now, the Lower Basin states of Arizona, Nevada and California and the Upper Basin states of Colorado, New Mexico, Utah and Wyoming are negotiating water conservation agreements as water levels in Lake Mead continue to decline.

The states have released draft agreements to implement drought-contingency plans in the Upper and Lower Basins after the Bureau of Reclamation predicted a shortage in Lake Mead — wherein water levels are projected to fall beneath elevation–1,075 feet above sea level — in 2020.

“To me, the law of the river emerges in an incremental fashion,” McCann said. “You solve what you can solve at the time and you leave other things for the future. This is just one more step in the evolution of water.”

The Western states have water agreements stretching back to the 1922 Colorado River Compact, which divided the states into two basins and distributed 7.5 million acre feet of river water each year per basin. Arizona had concerns about the water allocation and didn’t ratify the compact until 22 years later.

Another reason Arizona politicians agreed to the junior priority status in the Colorado River Act is because they believed they were getting a commitment to augment the flow of the river, McCann said. Augmentation would mean adding more water to the basin through options such as desalination or importing water from elsewhere.

But augmentation efforts are not cheap. And while the federal government studied the idea in 1975 and learned that eventually, there will not be enough water in the river basin to go around, it never started any sort of augmentation project.

While there is still more water available than necessary for current uses, the resources in the Colorado River Basin are finite and Arizona will likely be involved in water conversations for decades to come.