Integrated hydro–social modeling at catchment scale – a case for the Rhine basin

Climate change and socio-economical developments are increasing the pressure on available water resources. To realistically simulate changing water availability, natural hydrological processes and human water use need to be modeled following an integrated approach. While physical catchment information and meteorological datasets are readily available on a global scale, the collection of water demand data is often still a tedious exercise. Following Wada et al. (2016) a dataset was developed that integrates water demand information from amongst others EUROSTAT, AQUASTAT and the UN. The dataset is available for a variety of hydrological and water resources models. The dataset will be integrated in the Deltares Blue Earth initiative. This initiative provides a user-friendly framework for quickly setting-up an integrated modelling system. We have implemented a show-case for the river Rhine that focuses on the evaluation of the influence of socio-economic conditions on the water availability in the river catchment. With the Blue Earth-Model Builder the distributed hydrological model Wflow has been set-up for the Rhine catchment and the water resources allocation model RIBASIM has been schematized to integrate the natural water availability with water use to assess the human influences on the catchment’s resources. First results show that in the Rhine basin the water use by industry and households is small compared to cooling water use and irrigation. Looking into the future the uncertainty on changes in irrigation are especially large and are expected to increase most. We will further investigate how the influence of socio-economic changes compares to the influence of climate change. With the Model Building toolkit of Blue Earth, an integrated modelling system can consistently be schematized from global datasets in the central data store for any river basin in the world.