Water resources data for the 1977 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 in wells and spring. This report, in two volumes, contains discharge records for 258 gaging stations; stage only records for 4 gaging stations; stage and contents for 44 lakes and reservoirs; water quality for 162 stations, and 7 lakes; and water levels for 173 observation wells. Also included are 146 crest-stage 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 the U.S. Geological Survey and cooperating State and Federal agencies in Washington.