Jun 11 2018Share

Water Resources: The State Agency That Keeps Arizona Working

By Warren Tenney

A secure water supply fuels Arizona’s agriculture, tourism, mining, and even its power. Reliable water supplies are essential to attract industries with high paying jobs and meet the needs of homes, schools, hotels and hospitals. Without sustainable water our economic growth would stop. The Arizona Department of Water Resources (ADWR) is the state agency charged with helping to ensure that does not happen.

This crucial state agency grew out of the Arizona Interstate Stream Commission, which the State Legislature established in 1948. The commission’s primary task was to wage a successful U.S. Supreme Court Case against California, where the two states battled for access to Colorado River water. Arizona won. The court upheld the Colorado River Compact of 1922 and Arizona’s rights to a portion the river’s water. In 1973, the U.S. Bureau of Reclamation broke ground for the canal system that would transport Colorado River water to Phoenix and Tucson and be known as the Central Arizona Project. 

By the 1970s, the state was facing yet another water crisis. This time it was about the water in aquifers beneath our feet known as groundwater. In Arizona, aquifers hold mostly ancient waters that cannot be naturally restored by rain but can be depleted by over pumping. Although water users had been over pumping groundwater for decades, the state was shocked in 1976 when an Arizona Supreme Court ruling gave a private company, which grew pecans, the power to restrict the amount of groundwater used by the City of Tucson and several mining companies. Outraged cities and industries lobbied the legislature to form a 25-member commission to develop a comprehensive groundwater management law for the state. The commission's work culminated in the Arizona Groundwater Management Act of 1980, progressive legislation that continues to regulate groundwater pumping in Arizona’s most populated areas. The legislation also created the Arizona Department of Water Resources. For the first time, all responsibility for water planning, management and regulation was centralized in one agency.  Only the regulation of water quality remains the responsibility of the Arizona Department of Environmental Quality (ADEQ).

The Arizona Legislature has given the Department of Water Resources a multitude of mandates. Here are a few.

  • Prosecute and defend Arizona’s rights to Colorado River water.
  • Develop and implement plans to prevent depletion of groundwater supplies.
  • Determine whether new subdivisions have a 100-year assured water supply.
  • Ensure that new groundwater wells do not impact existing wells.
  • Issue permits for projects that help restore our groundwater supplies. 
  • Provide planning assistance to communities where water supplies are less reliable than in major metropolitan areas. 
  • Collect data about stream flows and groundwater levels, which is indispensable to understanding our current water situation and to plan for shortages.

Currently, the Department is responsible for vital negotiations with the other Colorado River Basin states and Mexico to shore up water levels in Lake Mead, a huge reservoir on the Colorado River behind Hoover Dam. If levels in Lake Mead continue to fall, the federal government will declare an official shortage of Colorado River water. That declaration would begin a series of cutbacks that would impact central Arizona farmers first, raise the cost of water for all CAP water users, and damage Arizona’s reputation as an arid state that knows how to manage water supplies. 

While the Department is leading Arizona's negotiations with other Basin states, it is simultaneously working with in-state water users to find ways to increase Arizona's water supplies.  One long-term idea under consideration is desalination of ocean water and groundwater that is too salty to use in its current state.  

For nearly 40 years, the Arizona Department of Water Resources has helped to ensure that Arizona has the water it needs for economic growth and for the health and welfare of its citizens.  These efforts were jeopardized during the recession when budget cuts decimated the Department's staff.  Governor Ducey and the State Legislature have wisely restored some of the Department's funding, but more is needed to make certain that this indispensable agency has the highly trained staff required to carry out its mandates.  All Arizona citizens will continue to be the beneficiaries.

For 49 years, Arizona Municipal Water Users Association has worked to protect our member cities’ ability to provide assured, safe and sustainable water supplies to their communities. For more water information visit

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