Hydropower intake-induced fish entrainment risk zone analysis

Abstract

Evaluating the impacts of hydropower intake operations on upstream aquatic habitat is important for the development of environmentally sustainable hydropower and flood protection. A computational fluid dynamics model was used to simulate the flow field in the forebay of a high dam, Mica Dam in British Columbia, Canada. The model was used to evaluate the upstream hydraulics under various operational conditions and reservoir levels. This model, which was verified by a novel means of collected acoustic Doppler current profiler field measurements, highlights how appropriate intake selection may limit the volume of the forebay occupied by the entrainment risk zone. Additionally, a potential flow solution was applied to predict the velocity field induced by the intakes and the limitation of the potential flow solution was assessed. By linking the detailed knowledge developed of the forebay hydraulics to the established body of knowledge of fish behaviour, fish habitat use within the entrainment risk zone is also discussed in the context of hydropower optimization.