The High Plains aquifer system underlies 174,000 square miles in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Approximately 20 percent of the irrigated land in the United States is in the High Plains, and about 30 percent of the ground water used for irrigation in the U.S. is pumped from the High Plains aquifer.
Nutrient data are available, to a varying degree, across the aquifer.
To characterize hydrogeology and water use. To identify the principal water quantity and quality issues.