Water resources data for the 1991 water year for New Jersey consists 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 95 gaging stations; tide summaries for 4 stations; stage and contents for 33 lakes and reservoirs; water quality for 101 surface-water sites. Also included are data for 67 crest-stage partial-record stations, 13 tidal crest-stage gages, and 91 low-flow partial-record stations. Locations of these sites are shown on Figures 11 and 12. Additional water data were collected at various sites not involved in the systematic data-collection program. Miscellaneous data were collected at 57 measuring sites and 13 water-quality sampling sites. 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.