Hydrological simulation of flow rates in (un)gauged catchments of East-Flanders (Belgium) by the SWAT+ and PDM models.

Hydrological models are key instruments to predict hydrological extremes, such as droughts and floods. These hydrological extremes are becoming more and more frequent in Belgium. Therefore, creating a climate robust water system is becoming a priority. This research aims to provide flow rate predictions for several catchments in the province of East-Flanders based on meteorological, soil, land use and DEM data. These were collected by local monitoring networks and transformed by, among others, local pedotransfer functions and spatial interpolation methods.

A physically based model (SWAT+) is used to simulate flow rate estimates for (un)gauged catchments and to calculate different scenarios related to land use change or a changing climate. The simulated flow rates are used as training data for a simple conceptual model (PDM). The PDM-model is more suited for real-time modelling and can be used as a basis to take policy decisions. The strength of physically based models is that they require minor calibration, while conceptual models have a more feasible computation time. By combining the strengths of both models, an estimate can be made for the flow rates in different (un)gauged catchments of East-Flanders.