"Since the center pivots’ debut some six decades ago, the amount of irrigated cropland in Kansas has grown to nearly three million acres, from a mere 250,000 in 1950. But the pivot irrigators’ thirst for water — hundreds and sometimes thousands of gallons a minute — has sent much of the aquifer on a relentless decline.... A shift to growing corn, a much thirstier crop than most, has only worsened matters. Driven by demand, speculation and a government mandate to produce biofuels, the price of corn has tripled since 2002, and Kansas farmers have responded by increasing the acreage of irrigated cornfields by nearly a fifth. At an average 14 inches per acre in a growing season, a corn crop soaks up groundwater like a sponge — in 2010, the State Agriculture Department said, enough to fill a space a mile square and nearly 2,100 feet high."
Read the full article here on the draining of the Ogallala aquifer.