A conceptual river model to support real-time flood control (Demer river, Belgium)

Model-supported real-time flood control requires the development of effective and efficient hydraulic models. Because of the large number of iterations required in optimization procedures, the hydraulic model needs to be fast. But at the same time, it should produce results with high accuracy. With view to achieving this target, a simplified but accurate conceptual model was established in this research. An identification and calibration procedure has been developed such that the conceptual model can be built and calibrated to a more detailed full hydrodynamic model. While doing so, also the robustness and stability of the conceptual model has been considered. The procedure has been tested for real-time flood control applications along the river Demer basin in Bel-gium. A detailed full hydrodynamic model, implemented in the InfoWorks-RS (IWRS) software was available for this case. Conceptual model building and calibration has been done based on two severe his-torical flood events in the years 1998 and 2002. Model testing was conducted based on the data for 2 other events. The model simplification is reached by lumping the processes in space. Water levels and discharges are simulated, not every 50 meters as the full hydrodynamic model does, but only at the relevant locations. These are the locations up- and downstream of the hydraulic regulation structures, to be considered by the real-time controller, as well as the locations along the river network where potential flooding is induced. Advanced conceptual modelling procedures have been considered based on separation of static and dy-namic storage along river reaches.