Water resources data for the 1981 water year for California consists of records of stage, discharge, gage-height, and water quality of streams; stage, contents and water quality of lakes and reservoirs; water levels and water quality of wells. Volume 3 contains discharge records for 158 gaging stations; stage and contents for 50 lakes and reservoirs; gage height records for 2 lakes; water quality for 23 stations; water levels for 53 observation wells, and water quality for 7 wells. Also included are 11 crest-stage partial-record stations and two water-quality partial-record stations. 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 California.