Economic motivation for raising coastal flood defenses in Europe

Extreme sea levels (ESLs) in Europe could rise by as much as one metre or more by the end of this century due to climate change. This poses significant challenges to safeguard coastal communities. This paper presents a comprehensive analysis of economically efficient protection scenarios along Europe’s coastlines during the present century by employing a probabilistic framework that integrates dynamic simulations of all ESL components and flood inundation, impact modelling, and a cost-benefit analysis of raising dykes.

The paper concludes that least 83% of flood damages in Europe could be avoided by elevating dykes in an economically efficient way along 23.7% - 32.1% of Europe’s coastline, specifically where high-value conurbations exist. The European mean benefit to cost ratio of the investments varies from 8.3 to 14.9 while at the country level this ranges between 1.6 and 34.3, with higher efficiencies for a scenario with high-end greenhouse gas emissions and strong socio-economic growth.