Water resources data for the 1979 water year for Michigan consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water temperature of ground water. This report contains discharge records for 175 gaging stations; stage only records for 1 gaging station; stage and contents for 5 lakes and reservoirs; water quality for 62 continuous-record stations; and water levels for 46 observation wells. Also included are 94 crest-stage partial-record stations and 45 low-flow partial-record stations. various sites, not part of the Additional water data were collected at 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 Michigan.