We monitored water quality in Falling Creek Reservoir (Vinton, Virginia, USA, 37.30325 -79.8373) with high-frequency (10-minute) sensors in 2018-2023. All variables were measured at the deepest site of the reservoir adjacent to the dam. Falling Creek Reservoir is owned and managed by the Western Virginia Water Authority as a primary drinking water source for Roanoke, Virginia. This data product consists of one dataset compiled of depth profiles of water temperature on 1m intervals from 0.1 to 9 m depth; dissolved oxygen at 5 and 9 m depth; pressure at 9 m depth; and temperature, dissolved oxygen, conductivity, specific conductance, chlorophyll a, phycocyanin, total dissolved solids, fluorescent dissolved organic matter, turbidity, and pressure at ~1.6 m depth.