Established by Laws 1980, Chapter 1, 4th Special Session, effective June 12, 1980. Statutory authority is found in A.R.S. Title 45; §45-101 et seq.
The Department administers all state water laws, except those related to water quality, which come under the jurisdiction of the Arizona Department of Environmental Quality. Created in 1980, the Arizona Department of Water Resources (ADWR) assumed the responsibilities of the Arizona Water Commission and the State Water Engineer relating to surface water, groundwater, dams and reservoirs.
Statute provides the Director of ADWR with general control and supervision of surface water (including appropriation and distribution) and groundwater (with exceptions spelled out in statute, court judgments or decrees). The Director is also authorized to act on behalf of the state on issues related to the Colorado River. (See A.R.S.§§45-103 and 45-107.) The Department also explores methods to augment water supplies and promote conservation. Arizona’s water supplies include surface water, including Colorado River water and in-state rivers; groundwater and reclaimed water.
The Arizona Territorial Legislature adopted the 1864 Howell Code, which established the doctrine of prior appropriation for surface water, used to allocate the right to use surface water for a beneficial use (“First in time, first in right”). Laws 1919, Chapter 164 created the State Water Code and established the office of the State Water Commissioner, who was appointed by the Governor to a six-year term. In 1922, the seven basin states negotiated a compact dividing the Colorado Basin into an upper basin and a lower basin and allocated 7.5 million acre feet to each basin. Arizona was allocated 2.8 million acre feet of water but refused to ratify the compact until 1944. Laws 1943, Chapter 28 transferred the responsibilities of the State Water Commissioner to the State Land Commissioner. Two years later, Laws 1945, Chapter 14, 1st Special Session transferred the authority to administer Arizona’s rights to Colorado River water to the State Land Commissioner.
In the 1930s, 1940s and 1950s the Legislature struggled to resolve issues related to groundwater use. In 1948 the Critical Groundwater Code was adopted, which prohibited drilling new irrigation wells in ten areas of the state designated as ‘critical groundwater areas.” The 1948 Code did not regulate pumping from existing wells however, allowing groundwater use to continue at historic levels. In response to criticism of the 1948 Code, a second groundwater study commission was formed in 1952. (Laws 1952, chapter 49.) None of the recommendations were enacted and the commission was abolished. In 1977, a 25-member Groundwater Management Study Commission was appointed to develop a comprehensive long-range plan for groundwater management by December 31, 1979 (Laws 1977, Chapter 29).
In June, 1980 Governor Babbitt issued a call for a special session to adopt a code to regulate and control the use of groundwater. Laws 1980, Chapter 1, 4th Special Session transferred responsibility to administer Arizona water laws from the State Land Department to a new agency, the Department of Water Resources. The 1980 Groundwater Management Act created four Active Management Areas (AMAs) with specific management goals and requirements to address groundwater overdraft. (Note: a fifth AMA was created in 1994.) Among other provisions, the act imposed restrictions on drilling new large wells within an AMA and required new subdivisions to demonstrate that a 100-year assured water supply is available to support the development. The act also addressed water conservation and transportation of groundwater.
Since the Department was created in 1980, a number of significant water policies have been enacted relating to conservation, recharge and underground water storage, artificial lakes, water transfer, tribal water rights settlements and interstate water storage agreements. Some measures expanded Department responsibilities, requiring the Department to provide administrative oversight, issue permits, monitor uses, or track and report data.
In 1986, the Legislature adopted the legal framework for groundwater recharge projects designed either to augment the groundwater supply (‘recharge projects’) or to store water underground for recovery in the future (‘underground storage and recovery projects’). The measure stated that stored water retained its character as either surface water or groundwater and also stated the ADWR Director was responsible for issuing permits for projects and establishing an accounting procedure for each source of water. The measure encouraged use of renewable water supplies, particularly Arizona’s Colorado River water entitlement through underground storage, savings and replenishment. See Laws 1986, Chapter 289 and Declaration of Policy, A.R.S. §45-801.01.
The Lakes Bill, enacted in 1987, limited the use of drinking water in artificial lakes constructed in the state’s active management areas. The measure required new lakes larger than an Olympic-sized pool, constructed after January 1, 1987, to be filled with effluent, storm-water runoff, poor quality water or water withdrawn to resolve water logging or water contamination. Certain uses were grandfathered or exempted from the prohibition. See Laws 1987, Chapter 238.
Groundwater transfers were addressed by Laws 1991, Chapter 212. The measure prohibited moving groundwater from an area outside an AMA to an AMA, unless specifically authorized. Four areas in the state were grandfathered with limitations on the amount of water that could be transferred (McMullen Valley, Butler Valley, Harquahala Irrigation Non-expansion Area, and the Big Chino sub-basin of the Verde River groundwater basin). See A.R.S. §§45-551 et seq.
A fifth active management area, the Santa Cruz AMA, which was initially part of the Tucson AMA, was established by Laws 1994, Chapter 296 as an emergency measure. The declaration of policy for its creation is found at A.R.S. §45-411.04.
The Arizona Water Banking Authority was established in 1996 to facilitate storage of Arizona’s unused Colorado River water, to provide an opportunity to the states of California and Nevada to store their share of unused Colorado River water, to facilitate storage and stored water lending arrangements for entities in Arizona, and to facilitate the settlement of Indian water rights claims by delivering and storing water. See Laws 1996, Chapter 308 and Declaration of Policy, A.R.S. §45-2401.
The Arizona congressional delegation worked for several years to resolve a number of tribal water claims. Laws 2005, Chapter 143 modified state law in order enact the components of federal legislation that resolved two water rights claims by Arizona Indian Communities: the Gila River Indian Community water settlement and the San Xavier Reservation water settlement. The measure also included the repayment settlement for the Central Arizona Project (CAP) and the water settlement for CAP.
The Secretary of Interior adopted guidelines in 2007 that provided for coordinated management of Lake Mead and Lake Powell during low water conditions. The seven basin states agreed to allow a water contractor to add water to the Colorado River system through conservation measures, efficiency projects or importation of non-Colorado River water in order to create ‘intentionally created surplus water’ (ICS). In 2007, the Legislature authorized the ADWR Director to enter into an agreement to forbear (or decline to exercise) Arizona’s right to intentionally created surplus water (ICS) in the Colorado River system. The forbearance agreement outlined specific conditions related to creation, release and accounting of ICS. See H.J.R. 2001, 48th Legislature, First Regular Session, as transmitted to the Secretary of State.
The Gila River and Little Colorado River general stream adjudications follow procedures outlined in state law. See A.R.S. §§45-251 through 45-264. The Arizona Superior Court is conducting the lengthy process of quantifying and prioritizing thousands of claims filed by persons and entities within the Gila River system and the Little Colorado River system. ADWR provides legal, technical and administrative support to the Special Master, who is appointed by the court under §45-255.
Laws 2017, Chapter 189 repealed a section of statute allowing summary adjudication of de minimis surface water uses. The section was repealed in response to an Arizona Supreme Court decision which held the section to be invalid and was replaced by language stating that water rights for small water use claims will be deferred until all other claims in that subwatershed are determined by the Court in the course of the general stream adjudication. See San Carlos Apache Tribe v. Superior Court, 193 Ariz. 195, 972 P.2d 179 (1999) and the DWR website: www.azwater.gov)
- A.R.S.§§45-101 et seq.
- Session Laws
- Laws 1919, Chapter 164
- Laws 1943, Chapter 28
- Laws 1945, Chapter 14, 1st Special Session
- Laws 1977, Chapter 29
- Laws 1980, Chapter 1, 4th Special Session
- Laws 1986, Chapter 289
- Laws 1987, Chapter 238
- Laws 1991, Chapter 212
- Laws 1994, Chapter 5
- Laws 1996, Chapter 308
- Laws 2005, Chapter 143
- House Joint Resolution 2001, 48th Legislature, First Regular Session, as transmitted to the Secretary of State (2007)
- Laws 2017, Chapter 189
- Laws 2019, Chapter 1, Chapter 2 and Chapter 263
Related Collections At Arizona State Archives
RG 59 – State Land Department
RG 141 – Interstate Stream Commission
RG 142 – Department of Water Resources