Evaluation of sediment concentration-discharge relationships for a monsoonal climate: Lake Tana Basin (original) (raw)

Abstract -- Increased concern for environmental sustainability has put more emphasis on predicting sediment concentrations rather than loads. Rating curves, relating sediment load to discharge, assume inherently a unique relationship of concentration and discharge and therefore although performing satisfactorily in predicting loads, it may be less applicable for predicting concentration. This is especially the case in the Blue Nile basin of Ethiopia where concentrations decrease for a given discharge during the course of the rainy monsoon phase. The objective of this paper is to improve the sediment concentration predictions throughout the monsoon period for the Ethiopian highlands. In this paper, we limit ourselves to the four main rivers in the Lake Tana basin where estimating sediment concentrations are important for the fish production and tourism industry. To improve the rating curve for sediment concentration, we assume that the sediment transport was at the transport limit ea...