Water resources data for the 1978 water year for Indiana consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs, and water levels in wells. This report contains discharge records for 194 gaging stations, stage and contents for 13 lakes and reservoirs, water quality for 49 gaging stations, and water levels for 59 observation wells. Also included are 124 crest-stage partial-record stations and 49 low-flow partial-record stations. Additional water data were collected at various sites, not part of the systematic data-collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal Agencies in Indiana.