The modelling area is an island in the river Rhine which is protected with dams against overland inundations. During flood events, large parts of the island are under artesian conditions and huge amounts of groundwater can leak to the surface. The purpose of the presented study is to analyse under which hydrological conditions this leakage can lead to flood risks for an industrial plant on the island. Critical hydrological conditions (peak and history) for inundation are derived from simulations of historical and artificial flood events. For this conditions flood propagation in the industrial plant is computed using a fully coupled groundwater - overland flow model. Together with the hydrological study this is used for risk analysis.