Unstable ground: How earth fissures wreak havoc on Pinal County
By Melanie Abramoff | Cronkite News
Areas of Pinal County are riddled with earth fissures that can open up at any moment. Some residents live in constant fear of the fissures in their own backyards, and county officials say they’re powerless to do anything about it.
The Arizona Geological Survey’s Michael Conway explained that earth fissures are the result of ground water pumping. “We’ve been growing crops in the Sonoran desert now for over a hundred years,” he said, “and for most of that time, it required extensive ground water pumping out of the aquifer below us, below our feet.” Conway said that as water is removed from underground, air replaces the gap; sediments in basin slowly come closer together until the floor subsides, causing a fissure to open up.
