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History of Water Management in Arizona

In Arizona, as in all arid regions, water means life. Arizona faces constraints on its water supply more severe than almost any other state in the nation.

The eternal problem of scarcity is obvious when we consider the etymology of the state’s name. “Arizona” is believed to have been derived from the Native American word “arizonac,” which means “the place of the small spring.”

Arizona’s major water problems are the stress consumption places on supply, and an imbalance between the places people live and where water is most abundant. Averaging less than 10 inches of rainfall per year, Arizona relies on groundwater for more than 40 percent of its water supply. Agriculture has historically pumped vast quantities of groundwater, and the state’s rapid population growth in recent years has amplified the use of groundwater for municipal and industrial purposes.

Keen-eyed new arrivals after the Civil War saw where long-gone Indian tribes had dug irrigation canals to let gravity bring the water to their crops in the large valleys of central Arizona. The settlers constructed a new network along those lines. A similar layout is being used to move water today.

Arizonans in the late 19th Century saw how winter rains and violent summer storms could turn a normally placid stream called the Gila River into frightening floodwaters. They also saw that all the water flowed away from their farmlands into the Colorado River and then to the sea.

They knew if the water could be captured and managed, Arizona’s fertile valleys could produce a bonanza of crops year-round. So they were ready when the U.S. government created the Department of Interior. A huge reservoir grew up behind the nation’s first federal dam, named after President Theodore Roosevelt, and there was bountiful water to irrigate cotton, citrus, and vegetables.

Areas outside the reach of the irrigation canals – which was most of the state outside the Phoenix area - still needed groundwater. Parts of Arizona had ample supplies of it, but it was being depleted at a rate of 2.5 million acre-feet a year. Since the early 1930’s, state officials have known action was required to control overdraft of the state’s groundwater basins.



Managing Water

Water management in the Southwest began with the Spaniards in the 16th and 17th centuries. Their overriding concept translated as “first in time, first in right.” Thus the doctrine of “prior appropriation” was born. It was bolstered in 1846 by an Army colonel named Stephen Watts Kearny. During the days of the Territorial Legislature, Judge William T. Howell issued a ruling that water rights were attached to the land (also known as “appurtenance.”) Appurtenance and prior appropriation were affirmed in 1910 by Judge Edward Kent, in what is known as the Kent Decree. The Public Water Code of 1919 set the decrees into law.

In the 1920s, waters of the Colorado River were divided among the seven states in the Colorado River Basin. Arizona’s allocation was for 2.8 maf, although the state could use only a fraction, at most 1.3 maf. Consumption was limited to Arizonans living along or near the shore. The rest was consumed in California, by Mexicans south of the international border, or it ended up in the Sea of Cortez.

In 1948, the Legislature established the Arizona Interstate Stream Commission. Its purpose was to secure Arizona’s rights to the Colorado and other interstate streams. Commission responsibilities also included statewide water resource planning. The Commission existed for 23 years, employing 17 people by 1971.
The Commission’s primary task was to prepare Arizona’s case against California in the U.S. Supreme Court, where the two states did battle over Colorado River water. Arizona won the case when, in 1963, the court upheld Arizona’s right to 2.8 maf under the Colorado Compact of 1922. Our victory in Arizona v. California made modern Arizona possible. It led, in 1968, to Congressional authorization of the Central Arizona Project.

With the April 13, 1971 signing of House Bill 3, the Arizona Water Commission replaced the Arizona Interstate Stream Commission. The new agency enjoyed expanded responsibility and authority, including oversight of dam safety, watershed management, hydrologic data collection, and licensing of weather modification projects. Administration of water rights continued to rest with the State Land Department.

Two years later, in May, 1973, lawmakers endowed the AWC with power to review the adequacy of water supplies for new subdivisions. The AWC reported its findings to the Real Estate Commission. (This was a predecessor to the current Assured & Adequate Water Supply program.)

Longtime residents remember the 1970s as a decade of massive, repeated flooding. Several intense floods occurred in 1972 and early 1973. In Maricopa County, all river crossings washed away except for Tempe’s Mill Avenue Bridge, the oldest span in the Salt River Valley. Flood control was the focus again in 1978-79. Many people were left homeless and millions of dollars in property damage occurred throughout the state.

The Groundwater Management Act

The 1970s also were when it all came together for water management in Arizona. Over the previous four decades, lawmakers had labored unsuccessfully to limit groundwater pumping. What was different in 1976 was the cities and the mining interests lost an important case at the Arizona Supreme Court when justices ruled a private company (pecan growers) could impose a limit on how much groundwater a municipality (Tucson in this case) and copper mines could pump. The cities and the mines demanded relief from the Legislature. Pretty soon the Legislature formed a 25-member groundwater commission to write a new groundwater law. After a year and a half of the members getting an education on water law, it was time for some decisions.

There were three issues over which great struggle ensued:

1. Who should have the right to pump groundwater and how much?
2. What methods should be used to reduce the groundwater overdraft?
3. Should groundwater be managed primarily at the state or local level?

Agriculture always has been the biggest groundwater user. Farmers wanted to keep things as they were, and proposed anyone who wanted to initiate pumping should have to purchase an existing right. The mines and cities objected, because they saw it as a bonanza for the farmers.

One of the commissioners complained, “We are not going to buy the farm so the farmer can move to La Jolla and raise martinis.”

The mines proposed that each acre in a groundwater basin receive a “quantified right” to water. More disagreements were in store. Agriculture wanted farmlands to be purchased and taken out of production, thus reducing groundwater pumping. The mines and cities felt everyone’s pumping should be reduced by the same percentage. Farmers, the biggest water consumers, would take the biggest hit.

The cities and mines brought things to a dangerous impasse when they garnered enough support to pass several provisions that angered agriculture representatives. The outcome looked in doubt.

Around this time, a well-rehearsed strategy was played out by the governor, Bruce Babbitt. He convinced the U.S. Secretary of the Interior, Cecil Andrus, to issue an ultimatum: unless Arizona enacted tough groundwater laws, he would refuse to approve construction of the Central Arizona Project.

Shocked back to reality, the cities, mines and agriculture asked Babbitt to mediate the discussions. One of the first items of agreement was creation of the Arizona Department of Water Resources.

In relatively short order, what was once considered impossible was a reality. On June 12, 1980, Gov. Babbitt signed the Groundwater Management Act (Code).
For the first time, all responsibilities for water planning and regulation, (except water quality) were centralized in one state agency. The Act designated four parts of the state where groundwater pumping was heaviest as Active Management Areas (AMAs).

The Department applied more stringent laws and regulations in the AMAs, including the requirement that a developer verify he has secured physical, legal, and continuous access to a 100-year supply of water. Since 1980, the Department has written and executed three of the five management plans required by the Code. The management plans outline conservation goals and methods for various groundwater users in the agricultural, industrial and municipal sectors.

The Code was the most eagerly-awaited and far-reaching policy initiative ever undertaken by the State. This progressive law granted vast, new responsibilities and authority. Arizona was recognized in 1986 by the Ford Foundation for its landmark work in water management.


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