This report presents water quantity and water quality data for samples collected at wells, springs, streams, and lakes in the vicinity of Mount Shasta in northern California. The data are presented in graphs and tables. Groundwater data include water level measurements made at 24 wells, analyses of water samples collected at 12 wells, discharge measurements made at 14 springs , and analyses of water samples collected at 17 springs. Surface water data include streamflow measurements and/or analyses of suspended sediment collected at 36 stream sites; analyses of water samples collected at 11 streamflow sites; profiles of temperature, specific conductance, dissolved oxygen, and pH for water samples from 6 lake sites; and analyses of water samples collected at 7 lake sites. Maps of the area show the location of data-collection sites. (USGS)