Impact of climate change, land use change, and residential mitigation measures on damage and risk assessment

Flood risk throughout Europe increased in past decades, and is projected to increase further due to continued development in flood prone areas and climate change. Several adaptation strategies can be used to limit this increase. These strategies include flood protection measures such as storm surge barriers and dikes, but also spatial zoning and flood proofing of houses. In recent years, studies have shown that adequate undertaking of flood-proofing measures can considerably decrease the costs of floods for households. However, there is little insight into how such measures can decrease the risk at the basin level, now and in the future. To gain such insights, a modelling framework using the Damagescanner model with land use and inundation maps for 2000 and 2030 was developed and applied to the Meuse river basin, in the region of Limburg, southeast Netherlands. The research suggests that annual risk may increase by up to 185 % by 2030 as a result of combined land use and climate change. Individually, the simulated increases due to land use change and climate change separately are 108 % and 37 % respectively. The implementation of spatial zoning measures decreases the risk by up to 45 %. Adaptation factors were subsequently applied to assess the potential impact of three adaptation strategies. Results show that the strategies could decrease the annual risk by up to between 21 % and 40 %, depending on their rate of implementation. Combining spatial zoning and mitigation measures could reduce the total increase in risk by up to 60 %.