Water resources data for the 2001 water year for Indiana consists of records of discharge, stage, and water quality of streams and wells; reservoir stage and contents; and water levels in lakes and wells. This report contains records of discharge for 163 stream-gaging stations, stage for 8 stream stations, stage and contents for 1 reservoir, water quality for 1 stream, water temperature at 11 sites, sediment analysis for 1 stream, water levels for 78 lakes and 88 observation wells. Also included are records of miscellaneous discharge measurements, miscellaneous levels and miscellaneous water-quality, not part of the systematic data-collection program. Data contained in this report represent that part of the National Water Data System operated by the U.S. Geological Survey in Indiana in cooperation with State and Federal agencies.