Rural coalition starts campaign to establish groundwater protection zone in McMullen Valley

A coalition of Arizonans in the western part of the state are banding together to protect their shrinking groundwater basin by establishing a zone to restrict pumping.

Residents are collecting signatures to establish a groundwater protection zone around the McMullen Valley aquifer.

A New York City based-hedge fund Water Asset Management, LLC, supported legislation earlier this year which would have allowed it to pump some of that water out and sell it to cities in the metro Phoenix area. The bill died, but it spurred locals to take action.

“I just think it’s morally wrong to take water from us that we need for development and survival and send it to Buckeye or wherever so that a family can build a new house and live there. Why are they more important?” McMullen Valley Water Defenders PAC leader Gary Saiter said.

Backers of the protection effort want to put the question of establishing an active management area (AMA) on local ballots next March.

The Arizona Department of Water Resources recently started the process of establishing an AMA in the neighboring Ranegras Plain Basin.

“You know, when the Ranegras Plain AMA got enacted, I did have my constituents out in the McMullen Valley basin asking, ‘You know, what about us? We need protection, too,’” La Paz County Supervisor Holly Irwin said. “So, it's not with lack of trying, it's just with the challenges with that basin the people said, ‘We're not getting the help down at the Legislature, so we'll try to do it ourselves and take it to the people for a vote.’”

Status of the aquifer

The McMullen Valley aquifer is in rapid groundwater decline.

ADWR compiled a supply and demand assessment of the aquifer in 2023. The report showed that as of 2022, for every 1 acre foot of water in the basin, 5 acre feet was leaving. In other words, the demand far exceeds the supply of groundwater.

A single acre foot is enough water to sustain about three single family homes for one year.

Much of the area surrounding the aquifer is farmland, and only a few thousand people live in the McMullen Valley.

The aquifer encompasses 720 square miles across parts of three counties: La Paz, Maricopa and Yavapai.

The effects of groundwater pumping have already taken a toll, Irwin said.

“Some of us have lost access to water. We see our land is sinking, and one of our schools has a football field that turned to dirt because a well failed,” she wrote in a statement.

The latest in a growing AMA movement

In 1980, four initial AMAs were established through the passing of the 1980 Groundwater Management Act. And a fifth split off of one of those four in 1994.

But from then until 2022, no new AMAs were established. That year, voters in the Douglas area approved a measure to create a new AMA.

Shortly after, Gov. Katie Hobbs’ administration took historic action to establish a new AMA in the Willcox basin.

Then ADWR — under Hobbs’ purview — moved to establish the Ranegras Plain Basin AMA in 2026.

There’s an important distinction between the initial AMAs and the efforts which started in 2022; the new AMAs are rural.

The original AMAs are all established around urban areas and are designed to work that way.

For that reason, lawmakers on both sides of the aisle agree that Arizona should come up with an alternative to AMAs that’s better suited to rural areas. However, Democrats and Republicans haven’t come to an agreement on what that should be.

For now, rural counties are continuing with AMAs as residents become increasingly concerned about groundwater supply.

The first 'transportation basin' AMA

The four groundwater basins were set aside as “transportation basins” in 1991.

State law prohibits transferring groundwater from one groundwater basin outside of an AMA into an AMA with the exception of those four transportations, including McMullen Valley.

That means cities like Phoenix and Scottsdale purchased thousands of acres of land in transportation basins years ago, which they can draw from in times of need.

The municipalities have never cashed in on that deal by taking groundwater from McMullen Valley, but that’s what residents fear will soon happen.

The cities of Buckeye and Queen Creek recently started the process of cashing in on the Harquahala Basin — another rural groundwater aquifer and transportation basin.

Arizona State University Kyl Center for Water Policy Director Sarah Porter said that doesn’t necessarily mean the basins will have less groundwater, because farmers in Harquahala will be compensated to let some of their fields fallow to offset the groundwater being taken away.

Just as municipalities drawing on transportation basins may not have any net negative effect on groundwater supply, Porter noted that establishing an AMA in McMullen Valley doesn’t touch its status as a transportation basin.

“Creating an AMA won't necessarily protect the basin from transportation,” Porter said.