Water-resources data for the 1980 water year for Washington 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-wells. This report, in two volumes, contains records for water discharge at 233 gaging stations; stage only at 5 gaging stations; stage and contents at 41 lakes and reservoirs; water quality at 39 gaging stations (including 6 lakes and reservoirs) and 100 wells; and water levels at 164 observation wells. Also included are data for 14 crest-stage and 89 water-quality partial-record stations. Locations of sites in this volume are on figures 4, 5, 6, and 22. 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 represent that part of the national Water Data system operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Washington.