Surface water modelling to mitigate flood damage

In an initial phase, the available data on the Blauwhuisbeek were supplemented with our own topographical measurement of the watercourse and its structures. These data, together with the existing measurement data, were incorporated into a hydraulic model of the existing situation in Infoworks-RS. This model was hydrologically and hydraulically calibrated using the available water level measurements on the river. Based on the model of he existing situation, a number of potential layout scenarios were extrapolated using the hydraulic model as a basis. This involved both modifications to hydraulic structures on the watercourse, introduction of a new river course, and establishment of floodplains at specific locations along the watercourse. This was at each instance coupled with a simulation of the hydraulic impacts and a further optimisation of the measures.

This study resulted in a number of alternative design scenarios with an estimate of their hydraulic impact. The preferred scenario was further optimised by developing in detail the location and height of dikes and the dimensions of the hydraulic structures. This resulted in a significant reduction in flooding at the critical locations.