In 2024, the State of Arizona designated the Willcox Basin as an Active Management Area (AMA) in a landmark decision aimed at curbing unregulated groundwater pumping that has plagued Cochise County for decades. The move came in response to mounting concerns over falling water tables, dry wells, land subsidence, and the emergence of earth fissures—issues that have threatened homes, infrastructure, and agriculture in one of Arizona’s most water-stressed regions.
The Willcox Basin
Cochise County, particularly the Willcox Basin, has long struggled with declining groundwater levels due to excessive pumping for both agricultural and residential use. Unlike other regions in Arizona that have access to surface water supplies like the Salt and Colorado Rivers (Salt River and Central Arizona Projects), Cochise County relies almost entirely on groundwater extraction. Over the years, deep aquifers have dried out, forcing well owners to drill deeper in search of water. Some wells have dropped by over 200 feet in recent decades, highlighting the severity of over-pumping.
The expansion of high-water-demand crops and large-scale cattle farms has further accelerated groundwater depletion, contributing to widespread land subsidence and the formation of earth fissures. These geological hazards occur when excessive groundwater withdrawal causes the land surface to sink unevenly. As aquifers shrink, the overlying sediments compact and collapse, leading to deep cracks in the ground. This phenomenon not only damages roads, homes, and farmland but also presents long-term safety and economic risks.
Overview of fissure locations in Cochise County
Groundwater levels in some major pumping areas have declined by 200 to 300 feet from pre-development levels. The Willcox Basin relies on natural recharge from surrounding mountain ranges, but this recharge is insufficient to sustain current withdrawal rates. As a result, the region has experienced a growing number of fissures, with significant formations appearing in the Sunsites and Cochise areas. Notable examples include a fissure on Parker Ranch Road near Sunsites in July 2024, another on North Arabian Road in Cochise in September 2024, and a previously documented fissure south of Willcox Playa in February 2023.
For years, Cochise County lacked formal groundwater regulations in this region, allowing large farms to pump unrestricted amounts of water. However, in response to increasing pressure from residents, scientists, and policymakers, the state took action in 2024 by establishing the Willcox AMA. The AMA introduces new regulations aimed at preventing further aquifer depletion and slowing land subsidence.
The Douglas area previously had an Irrigation Non-Expansion Area before being converted to an AMA in 2022. The Douglas basin runs from the southern end of the Willcox Basin to the U.S. border, west to Bisbee and east to the New Mexico line. It covers Douglas, Bisbee, McNeal, Elfrida, and Gleeson.
While the AMA marks a historic shift in water management for the region, it has not been without controversy. Some residents and business owners have voiced concerns over the broad regulations, arguing that a one-size-fits-all approach may not be the best solution. In response, the Rural Groundwater Management Act was recently introduced to give local authorities more control over water management, but it has yet to be passed.
Here is an overview on some of the regulations from an AMA:
Limits on how much groundwater can be pumped
Non-exempt wells (those pumping more than 35 gallons per minute) must be metered and reported to ADWR
Some areas restrict new wells or require replacement wells to meet efficiency standards
No new farmland can be irrigated with groundwater unless grandfathered rights exist
Grandfathered Water Rights:
Users with historical water use may have rights to continue, but they must comply with conservation and reporting requirements
Mandatory Conservation Programs:
Agriculture, industry, and municipal water providers must follow conservation requirements, such as reducing water loss and increasing efficiency.
Annual Water Use Reporting:
Certain water users must report their water usage annually to ADWR.
Well Spacing and Impact Analysis:
New large wells may require an impact analysis to ensure they do not negatively affect other users.
The graph below shows groundwater depletion over time at an irrigation well in the Kansas Settlement area. Depth to water level pre-development changed from around 50ft to more than 300ft post-development.
Although the AMA introduces restrictions that some fear may impact livelihoods, the alternative—unchecked groundwater pumping—would continue to push residents and farmers to drill deeper wells at an unsustainable rate. Without action, land subsidence and fissures will create long-term damage, increasing the cost of maintaining infrastructure and threatening the viability of agriculture in the region.
Ultimately, the challenge facing Willcox Basin residents is finding a balance between economic sustainability and responsible groundwater management. Through conservation efforts, improved technology, and continued regulation, it is possible to protect both the community and its vital water resources for generations to come.
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