Water Demand Simulation Using WEAP 21: A Case Study of the Mara River Basin, Kenya

Abstract

The competing water uses within the Mara River Basin MRB has increased water demand, which has affected the Mara river. In this paper, water resources and demands were modelled using Water Evaluation and Planning system (WEAP), by which different methods and strategies were assessed to mitigate the overuse practices from the Mara river. For this, water uses and resources in the basin were quantified and mapped in regard to their current and future statuses taking 2010 as a reference year for the simulation’ scenarios up to 2045. The Parameter Estimation Tool (PEST) was used to calibrate the model. The results showed that the total water demand within the basin under the reference scenario was 4.91 BCM, the demand dropped to 4.1 BCM under the ¨Demand Management Strategy DMS scenario and to 3.5 BCM under the Enhanced Policy Implementation and DMS scenario. The results also showed that the proposed DMS could increase water sustainability by reducing water demands at the basin.