Ogallala Aquifer

About 27 percent of the irrigated land in the United States overlies the aquifer, which yields about 30 percent of the ground water used for irrigation in the United States.

Since 1950, agricultural irrigation has reduced the saturated volume of the aquifer by an estimated 9%.

Depletion is accelerating, with 3% lost between 2001 and 2008 alone.

Certain aquifer zones are now empty; these areas will take over 100,000 years to replenish naturally through rainfall.