The outskirts of Kingman, Arizona, used to be a place where pilots would train and recreationists tested their all-terrain vehicles.

The dry and empty landscape has since morphed into something much more green that supports pistachio and almond orchards, as well as garlic and potato fields, in a climate similar to California's Central Valley. The crops are fed by groundwater that also serves the city of Kingman.

The Arizona Department of Water Resources this week put a limit on the amount of land that can be watered, designating the Hualapai Valley as an irrigation non-expansion area. That means anyone who hasn't farmed more than 2 acres there during the past five years can't.

It's the first such designation in Arizona in four decades — highlighting struggles around the U.S. as water supplies dwindle and tensions grow between farmers and cities. Just last week, a board that advises the Kansas governor voted to make a historic recommendation to protect the Ogallala aquifer, which has been tapped for decades to irrigate crops in an arid region.