Douglas R. Winter 1994 The U.S. Geological Survey, in cooperation with the South Dakota Department of Environmental and Natural Resources, has collected water-level data for 237 wells completed in bedrock aquifers throughout South Dakota. The water levels are presented in hydrographs in the main body of the report and in tables in a Supplemental Information section at the end of the report. The data are organized by county, in alphabetical order. application/pdf 10.3133/ofr94320 en U.S. Geological Survey ; USGS Earth Science Information Center, Open-File Reports Section [distributor], Water levels through 1989 in bedrock aquifers in South Dakota reports