Estimating Combined Loads of Diffuse and Point-Source Pollutants into the Borkena River, Ethiopia

Abstract

Estimating the relative contribution of heavy metals and nutrients loads from diffuse and point sources and various hydrological pathways is a major research challenge in catchment hydrology. Understanding of the transfer, loads and concentration of these loads in basins is useful in designing and implementing policies for the managements of surface waters. In sub-Saharan countries, few studies have been done to estimate heavy metals and nutrients transfers in catchments. It is usually difficult to obtain hydrological and hydro-chemical data even for smaller catchments. This Thesis presents the estimates of loads of heavy metals and nutrients from industry and land use into two rivers that flow through an industrializing catchment, additionally presents the selection and application of a model to estimate TN and TP loads in the Kombolcha catchments. The study of the transfer contaminants from diffuse and point sources illustrates management, capacity and policy needs for the monitoring of rivers in Ethiopia, and with relevance for other sub-Saharan countries.