The Usquepaug-Queen River ground-water reservoir in Rhode Island is part of the stratified-drift aquifer along the Usquepaug-Queen River and its tributaries. The thickest, most permeable parts of the aquifer form the Usquepaug-Queen River ground-water reservoir. The 36.1-square mile study area comprises parts of Washington and Kent counties, and includes parts of the towns of Exeter, North Kingstown, Richmond, South Kingstown, and West Greenwich. The report presents geologic and hydrologic information needed for the prediction and management of hydrologic effects of proposed ground-water development. The report describes aquifer lithology, provides historical data on water-level and aquifer-storage changes, provides information on ground-water quality, and presents natural flow characteristics and water quality of streams in the Usquepaug-Queen River area. The data includes 275 ground-water sites; lithologic logs of 66 ground-water sites; water levels for 43 ground- water sites; chemical analyses of 36 ground-water sites; stream discharge measurements from the continuous-record gaging station on the Usquepaug- Queen River; discharge measurements at 10 partial- record stations in the area; chemical analyses of 17 stream sites; and the data from 14 slug tests conducted at ground-water sites.