Active Management Areas, or AMAs, are areas within the state that are subject to certain statutory and administrative regulations regarding the withdrawal and use of groundwater, or in the case of the Santa Cruz AMA, the withdrawal and use of any water, other than stored water, withdrawn from a well. Currently, there are seven AMAs in Arizona –Douglas, Phoenix, Pinal, Prescott, Tucson, Santa Cruz and Willcox. All but the Douglas AMA and the Willcox AMA were designated by statute. The Willcox AMA was designated by Order of the Director of ADWR. 

Each AMA must have a management goal, which guides water management in the AMA. The management goals for the five initial AMAs are set forth in statute. The management goal for the Willcox AMA will be presented by the Director of ADWR during a public hearing. The Director of ADWR is required to adopt a management plan for each AMA that is updated on a periodic basis and that must be designed to assist the AMA in reaching or maintaining its management goal. Management plans for the other six AMAs can be viewed on ADWR’s website here. 

Another feature of AMAs is that they are subject to assured water supply requirements for new subdivisions. Within an AMA, a developer of a proposed subdivision (six lots or more) must have a 100-year assured water supply in order to obtain plat approval and offer lots for sale. A developer may demonstrate an assured water supply by either (1) obtaining a commitment of water service from a water provider that has been designated by ADWR as having an assured water supply, or (2) obtaining a certificate of assured water supply from ADWR by demonstrating that the subdivision will have a 100-year assured water supply.

The Willcox Groundwater Basin has been designated as an AMA by the Director of ADWR. The Willcox Groundwater Basin is located in Graham and Cochise Counties. A map of the boundaries of the basin is provided below, but is located generally in the northern Sulfur Springs Valley and is the entire surface watershed area that contributes to Willcox Playa plus the upper watersheds of Leslie Creek and Rucker Canyon that lie east of the Swisshelm Mountains in the Whitewater Draw watershed.

Proceedings to designate the Willcox Groundwater Basin as an AMA were initiated by the Director of ADWR on October 23, 2024, and since that time persons may only irrigate those acres of land within the AMA which were legally irrigated at any time during the five years preceding the date of the notice of the initiation of designation procedures. A.R.S. § 45-416.

“Irrigate” means to apply water to two or more acres of land to produce plants or parts of plants for sale or human consumption, or for use as feed for livestock, range livestock or poultry.

The limitation on the acres that may be irrigated within the area is permanent as result of the Decision of the Director of ADWR to designate the Willcox Basin an AMA, as described more fully in the response to Question No. 4 below. 

In a subsequent AMA (an AMA established after 1980), only acres of land that were legally irrigated at any time during the five years preceding the date of the notice of the initiation of designation procedures (October 23, 2024) may be irrigated with any water, except as provided below.

Acres of land that were not irrigated during the relevant five-year time period may be irrigated with a decreed or appropriative (surface water) right established before the date of the initiation of designation procedures.

Acres of land not irrigated during the relevant five-year time period may be irrigated if the Director of ADWR finds substantial capital investment (SCI) has been made to bring the land into irrigation within a particular window of time. SCI is discussed below at Question No. 7.

Within an AMA, a person may withdraw groundwater from a well having a pump with a maximum capacity greater than 35 gallons per minute (“non-exempt well”) only if the person holds a right or permit to withdraw the groundwater.

Generally, a person may withdraw groundwater for a non-irrigation use from a well having a pump with a maximum pump capacity of 35 gallons per minute or less (“exempt well”) without a right or permit. However, there are some limitations on the use of exempt wells within AMAs. Some of these limitations include:

• Only one exempt well may be used to serve the same use at the same location.
• Withdrawals from an exempt well for a commercial purpose are limited to 10 acre-feet per year.

Individuals and entities seeking to claim a grandfathered right are required to apply for a certificate of grandfathered right no later than fifteen months after the date of the designation of the AMA (by April 8, 2026), in accordance with A.R.S. § 45-476.

Grandfathered rights are withdrawal rights based on historic pumping. The qualifying time period for the Willcox AMA is October 23, 2019 through October 23, 2024 
The three types of grandfathered rights are: 

1. Irrigation Grandfathered Rights, which allows the holder to irrigate acres of land that had been irrigated within the qualifying time period. Land without an Irrigation Grandfathered Right may not be irrigated with groundwater. An Irrigation Grandfathered Right may not be sold apart from the associated land.
2. Type 1 Non-Irrigation Grandfathered Rights, which is associated with land permanently retired from farming and converted to a non-irrigation use: e.g., building a new industrial plant or a subdivision. This right, like an Irrigation Grandfathered Right, may be conveyed only with the land. The maximum amount of groundwater that may be pumped each year using a Type 1 right is three acre-feet per acre, though it may be less.
3. Type 2 Non-Irrigation Grandfathered Rights, which can only be used for a non-irrigation purpose. The right is based on historical pumping of groundwater for a non-irrigation use and equals the maximum amount pumped in any one year in the qualifying time period. Examples of non-irrigation uses include industry, livestock watering and golf courses. Type 2 rights are the most flexible because they may be sold separately from the land or well. In addition, the owner of a Type 2 right may, with ADWR approval, withdraw groundwater from a new location within the same AMA. It is possible to lease a portion of a Type 2 right, but if the right is sold, it may not be divided; instead, the entire right must be sold.

Cities, towns, private water companies and irrigation districts are required to obtain a service area right to withdraw groundwater for delivery to landowners and residents within their service area.

Groundwater withdrawal permits may be obtained through application to ADWR if certain criteria are met. Groundwater withdrawal permits allow pumping in specific circumstances, usually for non-irrigation uses, that are set forth in statute. These permits are for a limited period of time. Examples include the following:

• Hydrologic testing permits
• Poor quality groundwater withdrawal permits
• Temporary permits for electrical energy generation in emergency situations
• Mineral extraction and metallurgical processing permits
• Drainage and dewatering permits
• General industrial use permits

In a subsequent AMA, land that was not irrigated at any time during the five years preceding the date of the notice of the initiation of designation procedures “is deemed to have been in irrigation if substantial capital investment has been made for the subjugation of such land for an irrigation use including on-site irrigation distribution facilities and a well or wells the drilling and construction of which were substantially commenced before the date of the notice of the initiation of designation procedures ....” A.R.S. § 45-452(G)(1).  The qualifying time period for the Willcox AMA is October 23, 2019 through October 23, 2024

Property owners who believe they qualify for consideration of SCI may apply to ADWR, and ADWR will evaluate each application on a case-by-case basis.

Examples of documentation previously used by ADWR to make determinations on applications for the consideration of substantial capital investment (SCI) in granting a Notice of Groundwater Authority ("60") in an INA or Certificate of Grandfathered Groundwater Right ("78") in an AMA can be found on ADWR’s website here. These examples are being provided for informational purposes only. Please note that the standard for establishing SCI in statute differs depending on the location of the lands associated with the application. Therefore, some or all of these examples may not be relevant to all applications in this AMA.

Within AMAs, with a few narrow exceptions, persons withdrawing groundwater from non-exempt wells (wells having a maximum pump capacity greater than 35 gallons per minute) are required to measure their groundwater withdrawals with a measuring device and method that is approved by ADWR and must report the groundwater withdrawals to ADWR. ADWR has approved the use of devices and measuring methods other than the installation of meters as provided for in Arizona Administrative Code R12-15-903.

Persons withdrawing groundwater from exempt wells (wells having a pump with a maximum pump capacity of 35 gallons per minute or less that are used for a non-irrigation use) generally are not required to measure and report the groundwater withdrawals.

Under the current statutes, there is no requirement for persons withdrawing groundwater in a subsequent AMA (an AMA formed after 1980) to pay a groundwater withdrawal fee. There are other fees that may apply within a subsequent AMA, including, for instance, a water quality assurance fee applicable to persons who own a Type 1 or Type 2 Non-irrigation Grandfathered Right or who holds a groundwater withdrawal permit for beneficial use (See A.R.S. § 45-616).

The Director of ADWR will propose a management goal for the AMA and the number of years in which the goal is to be achieved. A.R.S. § 45-569(A).

The Director of ADWR is required to promulgate an initial management plan for the AMA not later than two years after the designation of the AMA. The Director may provide for subsequent management plans to be promulgated during the time set for achieving the management goal. A.R.S. § 45-569(B).

Prior to adopting the management goal and plan, the Director will conduct a public hearing on the proposed goal and proposed management plan in accordance with A.R.S. § 45-570. Residents will have an opportunity to provide oral or documentary evidence for or against the adoption of the management goal or plan.

In addition, the Governor will appoint members to a groundwater users advisory council (GUAC) for the AMA. The GUAC will consist of five members chosen to represent users of groundwater in the AMA on the basis of their knowledge of, interest in and experience with problems relating to the development, use and conservation of water. The GUAC will advise ADWR’s area director for the AMA, make recommendations on groundwater management programs and policies for the AMA and comment to the area director and to the Director of ADWR on draft management plans for the AMA before they are promulgated by the Director of ADWR. A.R.S. § 45-421(1).

Within AMAs, the calculation of water duties is made, at least in part, with reference to requirements contained in the management plans for the AMAs. Because ADWR will adopt management plans in accordance with the process described in response to Question No. 10 above, ADWR cannot provide information about how water duties would be determined at this time.

All Grandfathered Water Rights applications for the Willcox AMA will be accepted from January 8, 2025, to April 8, 2026. A person who fails to apply for a certificate of grandfathered right within an active management area waives and relinquishes any right to withdraw or receive and use groundwater pursuant to a grandfathered right (A.R.S. § 45-477.01).

Anyone who would like updates about the Willcox AMA can request to be added to an Interested Parties Email List by sending an email to Dennis Troutman, AMA Outreach Coordinator, at [email protected].
By signing up for the Interested Parties List, you will receive notifications for any future meetings and workshops related to the Willcox AMA.

Exempt wells are wells that are used for a non-irrigation use and that have a pump capacity of 35 gallons per minute or less. Within an AMA, exempt wells would continue to be subject to certain statewide requirements, including requirements that the well owner file a notice of intention to drill with ADWR, use a licensed well driller, comply with construction standards established by ADWR and file completion reports with ADWR. As is currently the case outside of AMAs, applicants for exempt wells that are located on a parcel of land of five or fewer acres that will be used for a domestic purpose must submit a site plan that, among other things demonstrates that the well will not be drilled within 100 feet of a septic tank or sewer system and demonstrates approval by the county health authority. A.R.S. § 45-596(F). Within an AMA, there are some limitations on the use of exempt wells, including the following: Only one exempt well may be used to serve the same use at the same location and withdrawals from an exempt well for a commercial purpose are limited to 10 acre-feet per year.

In AMAs, non-exempt wells may be drilled, replaced or deepened only with the approval of the Director. Those applications are subject to rules governing the location of new wells and replacement wells to “prevent unreasonably increasing damage to surrounding land or to other users from the concentration of wells.” A.R.S. § 45-598(A). Those rules may be viewed at R12-15-1301, et seq. https://apps.azsos.gov/public_services/Title_12/12-15.pdf. 

The Director of ADWR will establish a directory of all applications that are received for a certificate of grandfathered right and will provide a notice of the availability of the registry after the deadline for filing applications has passed (April 8, 2026). Any person residing in the AMA will be permitted to file a written objection to any application and request a hearing on the application within 180 days of the date of the Director’s notice. Objections may be made only on the basis that the information in the application is incorrect or insufficient to issue a certificate. Procedures for holding the hearings are set forth in A.R.S. § 45-480.

The Department evaluates water quality for Assured Water Supply applications under A.A.C. R12-15-719. Under that rule, the applicant can demonstrate water quality by certifying that the applicant or the proposed water provider will be regulated as a public water system by the Arizona Department of Environmental Quality (ADEQ) or another government entity with equivalent jurisdiction, unless ADEQ or another government entity with equivalent jurisdiction has determined that the water system is in significant non-compliance with water quality requirements. If the applicant or proposed water provider will not be regulated by ADEQ or another government entity with equivalent jurisdiction, then the applicant must submit a lab analysis to ADWR demonstrating that the water meets water quality requirements in accordance with A.A.C. Title 18, Chapter 4, or that the water will meet these requirements after treatment that is required by law. In addition, if the well or proposed wells from which the water will be withdrawn are within a mile of a WQARF site or Superfund site, the applicant must submit a contaminant migration and mitigation analysis, demonstrating that the water supply will continue to meet the requirements in A.A.C. Title 18, Chapter 4 for 100 years.

The Arizona legislature established two separate paths to designating subsequent AMAs. The legislature provided authority for local initiation of designation of an AMA on petition by ten percent of the registered voters residing within the boundaries of the proposed AMA, to be voted upon pursuant to the general election laws of this state. A.R.S. § 45-415. The legislature also vested independent authority to initiate designation procedures with the Director if the criteria in A.R.S. § 45-412(A) are met. Nothing in statute prevents the Director from designating a basin as an AMA based on the results of an election.

ADWR received and considered local input prior to making the decision to designate the Willcox Basin an AMA. After designation of an AMA, ADWR continues to receive and consider input from local stakeholders throughout the process of developing the management goal and management plans.

ADWR presented factual data related to hydrologic conditions in the Willcox Basin at the public hearing held pursuant to A.R.S. 45-413 in Willcox, Arizona on November 22, 2024. The hydrologic data presented at the hearing included data from 52 active wells that ADWR measures at regular intervals ("index wells") in the Willcox Basin and data from six basin sweeps in the Basin, where 4,627 additional well measurements were taken. More information related to the data collecting and testing done by ADWR can be found in the Technical Memo. ADWR also presented compiled groundwater statistical data, including water level change statistics from 2000 to 2020 for each of the 51 groundwater basins in Arizona, within ADWR Open File Report No. 20. In addition, outside of well data, ADWR presented evidence of land subsidence and land fissuring in the Basin.

The hearing recording and transcript can be found here. The Findings, Decision and Order issued by the Director can be found here.

In addition to limiting new uses of groundwater, the designation of an AMA will also lead to the adoption of a management plan that includes measures for reducing groundwater withdrawals. A.R.S. § 45-569(B).

After designation of a subsequent AMA, the Director must adopt a management plan, which will include conservation programs for both irrigation and non-irrigation uses of groundwater, including municipal and industrial uses. A.R.S. § 45-569.