Downstream changes in suspended sediment fluxes in the River Severn, UK

Movement of waves of fine sediment through catchment systems is important for what it can reveal about catchment dynamics. Previous studies have focused on "managed" systems; few have reported on natural flows from individual events. We report preliminary findings from an integrated study of downstream changes in suspended sediment transport during individual storm events in the upper part of the Severn. Downstream change in sediment transport is examined at four sites through detailed records of turbidity and discharge during three consecutive flood eventsin September 1994. Preliminary results indicate that while suspended sediment concentrations generally increase in the downstream direction for both storms, suspended sediment yield first decreases in the upper basin and then increases towards the lower basin. This trend has important implicationsfor water transport schemes and for modeling movement of pollutants.