Here’s some information on the Ogallala Aquifer, to give more of a background to that water crisis, which Annin touches on.
U.S. Geological Survey: High Plains Water-Level Monitoring Study
Scientific American: The Ogallala Aquifer: Saving a Vital U.S. Water Source (2009)
Bloomberg: Depletion of Giant Aquifer Threatens Vital U.S. Farmland (2015)
National Geographic: Texas Water District Acts to Slow Depletion of the Ogallala Aquifer (2012)