Digital map of aquifer boundary for the High Plains aquifer in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

This digital data set represents the extent of the High Plains aquifer in the central United States. The extent of the High Plains aquifer covers 174,000 square miles in eight states; Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. This data set represents a compilation of information from digital and paper sources and personal communication. This boundary is an update to the boundary published in U.S. Geological Survey Professional Paper 1400-B and Open-File Report 99-267.