Watershed management modelling in Malawi: application and technology transfer

To study the possible impact on the Lake Malawi/Nyasa/Niassa water quality due to actions performed at the watershed level, a modelling project supported by the World Bank, was conducted by the United Nations University, the University of Waterloo and WL Delft Hydraulics to integrate physical and bio-chemical processes models in the lake and its basin which affect lake and river water quality. The purpose of the integration of different models was to provide a set of tools in order to analyze the impact on the lake due to actions performed in the watershed. In this paper, we present the watershed and lake box models integration and a case application to find how agricultural practices and deforestation may impact on the water quality of rivers and streams which will then lead to changes in the nutrient loading to the lake.