Water resources data for the 1980 water year for New Jersey 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 quality of ground water. This volume of the report contains discharge records for 27 gaging stations; tide summaries for 3 stations; stage and contents for 16 lakes and reservoirs; water quality for 59 surface-water sites and 95 wells; and water levels for 16 observation wells. Also included are data for 27 crest-stage partial-record stations, 7 tidal crest-stage gages, and 19 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 U.S. Geological Survey and cooperating State and Federal agencies in New Jersey.