Flood risk management through a resilience lens

de Bruijn, K.M., Jafino, B.A., Merz, B. et al. Flood risk management through a resilience lens. Commun Earth Environ 3, 285 (2022).

To prevent floods from becoming disasters, social vulnerability must be integrated into flood risk management. We advocate that the welfare of different societal groups should be included by adding recovery capacity, impacts of beyond-design events, and distributional impacts.

Societies have prospered in river valleys, deltas, and coastal areas thanks to effective strategies to cope with flood hazards. However, floods have been increasing in frequency and severity due to climate change and increasing exposure. Governments worldwide aim to develop strategies to reduce flood risks, usually favoring the measures with the largest risk reduction benefits and the lowest costs for a range of sufficiently likely hazard events. Here, the costs conventionally considered are the direct damages.

The high impact of recent extreme but rare events such as the 2022 floods in Pakistan and Malawi, the July 2021 flood in Northwestern Europe, the devastation due to Hurricane Iota in the Central Americas (2020), or the 2017 flooding of Houston, Texas, have brought us to rethink flood risk management. In conventional risk analyses rare, extreme events typically have little importance, because the expected annual damage–the indicator of conventional risk approaches–is often dominated by events that have a high probability but cause relatively low damage. Risk reduction measures conventionally aim to reduce direct impacts and total flood risks while minimizing costs. In contrast, it is rarer for measures to be implemented that enhance the ability to cope with flood hazards and to recover rapidly, to reduce indirect flood effects and to account for the distribution of impacts over wealthier and poorer communities1This may result in strategies that amplify existing inequalities, promote already wealthy societal groups2 and neglect disastrous outliers.

Climate change and the related increase in flood hazards require additional investments into flood risk management. This opens a window of opportunity to ensure new investments contribute to a fairer and more resilient world. We argue that policy makers should adopt a resilience lens that utilises more comprehensive analyses, rooted in societal welfare.