Water resources data for the 1991 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 2 contains discharge records for 130 streamflow-gaging stations, 1 low-flow partial-record station, and 6 miscellaneous measurement sites; stage and contents for 7 lakes and reservoirs; precipitation records for 3 stations; and water-quality records for 41 streamflow-gaging stations and 3 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.