LA PAZ COUNTY, Ariz. — There's water underground in La Paz County. The only problem is, no one really knows how much that amount is.

And what's worse, no one knows how fast it's being excreted.

La Paz County, about 90 minutes west of Phoenix, is mostly brown desert dotted with green fields. He has one or two canals running through the farm, but the water mainly comes from underground wells.

“If we don't know what's underground, how can we determine what the demand and supply will be?” said La Paz County Supervisor Holly Irwin.

Water is everything in La Paz County. This is the center of controversy over Fondomonte, a Saudi alfalfa grower that has bought up thousands of acres of land. Alfalfa is one of the most water-intensive crops to grow, and Fondomonte ships it back to Saudi Arabia to feed its dairy cows.

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Local politicians are looking to tax Fondomonte and other foreign-owned businesses, but it's not just foreign farms that are crippling La Paz County.

In Arizona, there is something called Active management area. These are areas that are highly dependent on groundwater and whose use is closely tracked. La Paz County is not included in any of these zones.

La Paz has no restrictions. That is, anyone with a well can pump as much water as they want and no one will keep track of it. Irwin wants a hydrological study to find out how much water is left in the county.

“We know funding is a big part of that,” Irwin said. “The county does not have the funds to conduct a hydrological study.”

But funding is not the only issue. Experts say it is very difficult to measure the amount of groundwater in a location. After all, this isn't some kind of underground lake you can tap into.

“It's not just these layers or pockets of water that exist,” says Sarah Porter. Arizona State University Kill Water Policy Center He explained. “What we're talking about is water that's held in the tiny spaces between the Earth's layers of matter.”

In other words, groundwater is basically mud and sand mixed with water. Measuring the moisture content of invisible soils and rocks is nearly impossible, but not perfect.

“It's very difficult,” Porter said. “Hydrologists basically have to figure out the shape of the aquifer. And then they can extrapolate down to a certain depth.”

In La Paz County, such estimates have not made much progress, so experts do not know the current situation. Wells in the county's rural areas don't have to be metered, so they don't even know how much groundwater they draw each day.

“Not only do we need to know how much water there is, we also need to know how much demand we actually have,” Porter says.

For example, Fondomonte received state approval to build a new well that can pump 3,000 gallons per minute. This equates to more than 15 trillion gallons per year. But no one knows how much it will pump or when it will happen.

To put these numbers into perspective, a standard bathtub only holds about 80 gallons of water. That's a large number of bathtubs, and Irwin worries that homeowners will soon feel the effects.

“There will be people who will come here just to market that water and make millions of dollars,” Irwin said.

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The county is still in litigation with a water investor who purchased land in La Paz County and wanted to transfer water to the town of Queen Creek.

Mr Porter said there were many hoops to jump through for potential water investors to do the same in the future. But the fact that it happened even once is enough to worry Irwin.

Wells in La Paz County continue to operate, but no one is looking at them.

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