Water resources data for the 1981 water year for New York consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels of ground-water wells. This volume contains records for water discharge at 105 gaging stations; stage only at 6 gaging stations; and stage and contents at 4 gaging stations and 19 other lakes and reservoirs; water quality at 29 gaging stations, 5 precipitation stations and 4 partial-record stations; and water levels at 23 observation wells. Also included are data for 50 crest-stage and 14 low-flow partial-record stations. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data together with the data in Volumes 2 and 3 represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in New York.