Continuing studies are being made in west-central Kansas to provide up-to-date information to aid in the management of groundwater for irrigation. This report presents the fifth in a series of studies that uses a statistical technique, called kriging, to produce hydrologic maps that are used as management tools. Kriging is a statistical technique that was used to interpolate water level altitudes at the center of each 1 sq mi section in the study area based on measured water levels at 165 observation wells. These interpolation altitudes (1,859 in all), along with bedrock surface and base year water table altitudes, were used to prepare a geohydrologic map illustrating percentage change in saturated thickness. Saturated thickness, as used in this report, is the thickness of the High Plains aquifer between the groundwater surface indicated by water table altitudes and the bedrock surface. Because irrigation development in west-central Kansas was minimal prior to 1950, the saturated thickness during 1950 represented a nearly static condition in the aquifer. Apparent increases in saturated thickness generally occurred in areas of sparse data or thin saturated thickness, and large errors were possible; therefore, zero and negative-change areas were not contoured. A decrease in saturated thickness of 100% may indicate that: (1) the aquifer has been dewatered, or (2) no saturated thickness occurred in that area during 1950. In general, percentage change in saturated thickness indicates the degree of stress on the aquifer in most areas due to irrigation pumpage. (Lantz-PTT)
Additional publication details
USGS Numbered Series
Percentage change in saturated thickness of the High Plains aquifer, west-central Kansas, 1950 to average 1983-85
Water-Resources Investigations Report
1 map : photocopy ; 66 x 131 cm., on sheet 83 x 142 cm., folded in envelope, 33 x 25 cm.