Arizona groundwater is in trouble. But how much longer does it have?

Jul 26, 2023

It’s easy to look at the “bathtub ring” at Lake Mead and realize we’ve got a problem.

The bleached-white cliff walls show us how far water levels have declined — more than 100 feet from the reservoir’s peak in the 1980s.

It’s a lot tougher to see how quickly Arizona is depleting groundwater, though the declines may be just as significant.

In fact, we know surprisingly little about what for many communities is their only water source.

Sure, there are tell-tale signs of trouble in some places, including dry wells and giant cracks in the ground.

Yet for many of Arizona’s 46 groundwater basins — particularly the rural ones that have no regulation — it’s tough to answer even basic questions about the health and sustainability of this critical water supply.

Many basins have no comprehensive surveys of the aquifer that lies underneath. Others are woefully outdated.

Users in most rural areas aren’t required to report how much water they are pumping.

And the number of index wells — those Arizona uses to periodically take readings on the depth to water below — has fallen steadily over time.

When properties change hands, the new owners are often reluctant to let the state capture this data, officials have said.

All of which adds up to giant holes in what we know about groundwater, even if it makes up a greater share of our state’s water supply than water from Lake Mead.

This is not just an Arizona problem.

As a New York Times analysis reminds us, lots of states heavily rely on groundwater.

Yet few closely monitor or have set meaningful ground rules on use because, as in Arizona, they lack the political will to do so.

And that is taking a toll.

The Times tracked water levels at more than 84,000 wells nationwide and found that nearly half had experienced significant declines since 1980.

It also noted that several states — including Texas, Oklahoma and Colorado, which according to the analysis also experienced some of the most extensive groundwater declines — allow groundwater to be pumped until it’s gone.

Can we fix groundwater?Depends on how we answer 3 questions

In Arkansas, The Times reported, some areas have depleted their aquifers so severely that less than 10% of their capacity remains.

It’s a similar story across the globe, where extended drought and decades of heavy pumping are decimating local supplies, with little reliable data to inform efforts that could counteract it.

As one expert quipped during a recent multinational water forum, “we’re driving a car without a fuel gauge.”

Arizona needs to know how quickly it is using this metaphorical gas — particularly in groundwater basins like Willcox, Gila Bend and the Ranegras Plain in La Paz County, where the few readings we do have point to calamity on the way.

Because unlike a regular tank, when water is removed from an aquifer and underground sediments collapse, they can’t be refilled.

I know. That doesn’t guarantee we’ll do something about it before the engine starts sputtering.

After all, the giant bathtub ring has for years made plain the problem at Lake Mead, which is that we still use more water than the Colorado River produces.

Yet the best solution we’ve come up with so far is to pay people to temporarily not use water.

But the more detail we can provide about groundwater — particularly for those with no other water source — the more it enables us to have the frank discussions that every unregulated basin should be having about its future:

Is the goal to prolong the life of your aquifer? And if so, for how long?

Or is it to simply pump ‘em while you got ‘em and move on when you can’t?

Reach Allhands at [email protected]. On X, formerly Twitter: @joannaallhands.

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