Reducing Groundwater Overdraft to Protect People and Farms: ADWR staff brief Willcox draft AMA Plan

ADWR staff on April 8 traveled to Willcox to share with residents some of the opportunities that lay ahead as ADWR and stakeholders of the new Willcox Active Management Area work together to find solutions to the alarming rate of groundwater depletion within the basin.

The public meeting served as an information session and public workshop. The “workshop” portion included some how-to instructions to help water users file grandfathered groundwater rights applications, which are due in April 2026.

As for the informational portion of the meeting, ADWR staff presented attendees with essential details about current groundwater conditions – which, for a thriving agricultural community that relies solely on groundwater, presents real challenges.

ADWR Water Resource Specialist Madison Moreno framed the situation in Willcox: In other Arizona AMAs, especially those with access to supplies of Colorado River water, water users can turn to renewable options to replace groundwater extraction and increase water supplies.

“In Willcox, it’s a different story,” she said. “The only meaningful option is to reduce demand.”

The ADWR team laid out the stark conditions facing the region, which is experiencing an annual overdraft of groundwater supplies of over 100,000 acre-feet, according to ADWR estimates.

In the last ten years, at least 71 wells have gone dry, according to ADWR monitoring data. Subsidence – lowering of the land surface largely caused by groundwater mining – stands currently at more than 11 feet in the areas around Willcox. And the rate of subsidence is accelerating, increasing from 1.2 inches per year in 1996 to 2.8 inches per year in 2023.

The consequences of that rapid groundwater depletion are alarmingly evident in other ways.

Earth fissuring – the often sudden appearance of splits in the earth, a direct result of groundwater mining – has jeopardized roads and even homes in the Willcox area, which has recorded over 50 miles of fissuring as of 2023. This sinking land and dramatic earth fissuring threatens, homes, businesses, and infrastructure.

Each AMA has its own Management Goal which serves as the “north star” to address groundwater challenges. ADWR team originally presented a Draft Management Goal for the Willcox Basin in January for residents and water users to review. After reviewing the comments, recommendations, and proposed changes supplied by Willcox AMA stakeholders, ADWR revised the Willcox AMA Management Goal to the following:

“To support the long-term viability of the regional economy, mitigate land subsidence, and extend the life of the aquifer by reducing groundwater overdraft by at least 50 percent by 2075.”

“Overdraft” is a term that refers to the volume of groundwater extracted from the aquifer in excess of what is being replenished. In the Willcox Basin, overdraft is severe, currently over 100,000 acre-feet each year is pumped in excess of what is annually recharged back into the aquifer.

In order to address its substantial overdraft the first Management Plan for the Willcox AMA will need to set mandatory conservation requirements that include “volumetric groundwater withdrawal reductions,” as well as other conservation measures.

“The hydrological challenges are going to be difficult,” acknowledged Moreno.

Virtually all residents attending the meeting at the Willcox Community Center acknowledged the challenges their region faces with its water supplies.

“We know this is going to be difficult. We appreciate ADWR’s work,” said Willcox farmer Tedd Haas.

Some attendees noted with concern that the goal to reduce overdraft by 50 percent within 50 years was impactful and ambitious, but others acknowledged that conditions warrant serious efforts to address the issue.

“At this point, we are all aware of the deep concern for our basin groundwater,” said Lisa Glenn. “Putting our groundwater in a deficit of 110,000 acre-feet a year… this is not sustainable.”

Glenn called for “flexibility and funding” to attain the management goal.

“We have no rivers, streams or lakes to replenish our aquifer. There must also be flexibility and funding. And to reduce our groundwater overdraft, we must have the data.”

In the coming months, ADWR will continue to work with Willcox AMA stakeholders and water users to develop conservation and water use reduction programs to help the community and groundwater users within the region have a secure groundwater supply well into the future.