Water resources data for the 2002 water year for Louisiana 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 report contains records for water discharge at 85 gaging stations; stage only for 79 gaging stations and 7 lakes; water quality for 52 surface-water stations (including 40 gaging stations) and 104 wells; and water levels for 300 observation wells. Also included are data for 143 crest-stage and flood-profile partial-record stations. Additional water data were collected at various sites not included in 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 Louisiana.