Integrated flood risk management approaches are implemented in many countries worldwide (Merz et al., 2010;Sayers et al., 2013). These approaches consider that flood defenses might fail and focus on mitigating the consequences of flooding, acknowledging that entirely preventing floods is not possible. In Germany, the events in 1993, 1995 and the extreme event in 2002 triggered various policy decisions toward more systemic risk management approaches (Petrow et al., 2006;Rözer et al., 2020).Nationwide risk assessments are important to support national risk management and climate change adaptation policies (Merz et al., 2010). The European Flood Directive (ES, 2007) requests the European Union member states to provide risk management plans for all areas with potentially significant flood risk. After