Modelling the impact of Bui dam operations on downstream competing water uses

Development of dams has the potential of causing the loss of many environmental and social benefits for riparian communities. The alteration of the natural flow regime on the downstream can adversely affect the competition for water and livelihoods that depend on them. This work examined the potential impacts of the development and operation of the Bui Hydropower Dam on downstream competing water uses by using the Water Evaluation and Planning (WEAP) tool. The significant competing water uses in the study area include Domestic, Livestock and Industrial purposes. The above-mentioned in addition to environmental flow requirements and the contribution of the Black Volta River to the Volta Lake were estimated. A model was set up to simulate the operation of the Bui Hydropower Dam. The model was calibrated and validated to make it applicable for the intended purpose. The main finding of the research is that the current operations of the Bui hydropower dam does not adversely affect competing water uses downstream of the dam. The model indicates that the runoff from the reservoir will differ considerably from the predicted regulated flow from the Environmental and report, but not much compared to the long-term average. All demands for domestic, livestock and industry were satisfied in all monthly time steps of the model. The results indicate that unless there is a significant change in the operation of the dam, any serious impact on the competition of the water resource cannot be attributed to the dam.