Extensive field measurements of flow in vertical slot fishway as data for validation of numerical simulations

Abstract Fishways are of great ecological importance and have been the focus of numerous studies. However, many fishways remain operating at an unsatisfactory level. Furthermore, field measurements of flow properties in effective fishways remain surprisingly rare compared to the number of various numerical and physical hydraulic models. The purpose of the research was to conduct extensive field measurements of the flow in an effectively operating vertical slot fishway (VSF), and to use the findings to calibrate and verify the depth-averaged two-dimensional (2D) numerical hydraulic model PCFLOW2D. Flow velocities were measured using a reliable 3D acoustic probe. Measured velocities were up to 50% larger than values calculated from an equation proposed in recent literature, but in accordance with results of our simulations. PCFLOW2D proved to be a useful tool for modeling fishway flow and could be used in similar hydro-environmental problems.