Arizona's groundwater supply could not adequately support the drastic population boom this arid southwestern state experienced in the 1970s. Since Arizona receives an average of less than 10 inches of rainfall per year, residents have traditionally relied primarily on groundwater for agricultural, industrial, and household use, but these wells were rapidly drying up. Over the past thirty years, the underground aquifers were drawn down at an alarming rate with residents consuming approximately 2.5 million acre-feet more groundwater than is naturally replenished each year. Depletion was greatest in counties containing major metropolitan areas, such as Phoenix and Tucson. Excessive groundwater pumping resulted in myriad problems including land subsidence, earth fissures, water quality degradation, increased pumping costs, and most importantly, the threatened availability of water for future generations.
By the late 1970s, after decades of heated political contention, Arizona state leaders recognized the need to protect the State's most vital resource. Understanding the critical need for agreement among all the major water interests, the governor, along with the legislative leadership and representatives of agricultural, mining, and municipal water users, established the Groundwater Management Study Commission. The Commission agreed to the adoption of a comprehensive Groundwater Management Code and the creation of a new State Department of Water Resources in 1980. The Code's ultimate goal is to reach a safe-yield, a balance between groundwater withdrawals and replenishment, by the year 2025.
The Groundwater Code concentrates regulation to four Active Management Areas (AMAs), where groundwater is used most intensely. A complex set of planning requirements and conservation measures determines the legal rights to the groundwater with the service areas of municipalities clearly defined. Each AMA must produce a comprehensive water management plan every decade, setting goals and mandating conservation measures for each sector. The Code's provisions "grandfathered" existing agricultural use but capped this use at its current level. For the first time, sellable water rights were granted, creating a new market for access to groundwater. In addition, the Code established an innovative permitting system specifically for industrial and mining use. The State also imposed a pump tax and, for the first time, required metering and reporting of absolutely all water use. Sprawling development was halted with the provision that new housing could not be constructed unless the developer could guarantee an "assured water supply" for the next 100 years. In order to effectively implement all aspects of the Code, the Department of Water Resources was allotted the necessary enforcement powers, including cease and desist orders, civil fines, and criminal sanctions.
In a historically conservative state with residents who are often suspicious of government regulations, the Groundwater Management Code has still earned widespread public, legislative and judiciary support. The key to the program's acceptance is its high level of intergovernmental cooperation and involvement of all levels of public and private sector organizations. Most importantly, the Code has dramatically increased awareness and understanding of the need to manage and to conserve Arizona's water supplies.
Approximately 99 percent of the State's major water consumers now closely monitor their use of water. The executive director of a large water and electric power utility company stated that the Code "changed the development ethic of the state ('build where you want and water will be there') and set a clear objective ('safe-yield by 2025')." Fundamental assumptions of property rights and development patterns have been challenged by the new policy. The Groundwater Management Code forces both developers and residents to incorporate water conservation into their investment decisions and daily actions, ensuring Arizona a steady water supply so that the State can continue to prosper well into the future.