Digital map of changes in water levels from predevelopment to 1980 for the High Plains aquifer in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

This digital data set consists of contours of predevelopment to
1980 water-level elevation changes for the High Plains aquifer
in the central United States. The High Plains aquifer extends
from south of 32 degrees to almost 44 degrees north latitude and
from 96 degrees 30 minutes to 106 degrees west longitude. The
outcrop area covers 174,000 square miles and is present in
Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South
Dakota, Texas, and Wyoming.

This digital data set was created by digitizing the contours for
predevelopment to 1980 water-level elevation change from a
1:1,000,000-scale base map created by the U.S. Geological Survey
High Plains Regional Aquifer-System Analysis (RASA) project
(Gutentag, E.D., Heimes, F.J., Krothe, N.C., Luckey, R.R., and
Weeks, J.B., 1984, Geohydrology of the High Plains aquifer in
parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South
Dakota, Texas, and Wyoming: U.S. Geological Survey Professional
Paper 1400-B, 63 p.) The data are not intended for use at
scales larger than 1:1,000,000.