In 2014, Almarai, a Saudi dairy company, began buying and leasing land near Butler Valley, northwest of Phoenix, to grow alfalfa to ship back to Saudi Arabia to feed their cows to make yogurt and cheese. Why does a Saudi dairy company find it worthwhile to grow its cow feed all the way over in Arizona?

"What makes Arizona special is that when you have this desert land, you can grow alfalfa at an incredibly fast rate because of the amount of sunshine. So, as long as you have plentiful water, you can just grow," says Natalie Koch, professor of geography and the environment and author of "Arid Empire: The Entangled Fates of Arizona and Arabia" (Verso Books, 2022).

The land Almarai licensed came with as much groundwater as they could pump because it's located outside of Arizona's active management areas. Once they obtain a permit to drill a well there's no monitoring of how much water they are pumping.

"To know then that big agricultural things like these alfalfa farms continue is really troubling. But it’s only possible because there’s no real cost on it," Koch says. "So, getting some kind of regulation mandated across the entire state, I think is the first thing that needs to happen."

Listen to the full interview on Freakonomics Radio (segment begins at 38:00).