New analysis indicates European cities and countries with highest expected losses from future flooding

Flooding – the most expensive natural hazard in Europe – is forecast to worsen in the future due to climatic and socio-economic changes.

This study provides a large-scale risk assessment of river-based flooding in Europe for the years 2025, 2055 and 2085 — to estimate flood losses to homes.

Floods affect more people globally than any other natural hazard. Fluvial flooding usually happens when a significant amount of rain falls over a long time, causing rivers to rise and overflow onto surrounding land. Climate change is expected to increase the amount and frequency of rainfall in the future, so flood losses and the number of people affected by river floods in Europe, will also rise. Societal changes have also led to more people living on floodplains over the last few decades, increasing the potential damages from river flooding. In 2002, the European Union Solidarity Fund was set up to aid Member States when natural disasters occur, as a response to severe flooding in Central Europe.

To enable better adaptation planning and improved flood-risk management, it is important to understand the drivers of risk under different climate, socioeconomic and private flood-precaution scenarios.

This study offers the first high-resolution assessment of future flood risk in Europe including changes across three key components: hazard, exposure and vulnerability. The model quantifies future flood risk in Europe, showing hotspots and trends where targeted interventions may be useful. Importantly, this evaluation includes resistance factors to flooding, such as precautionary measures taken by homeowners to ameliorate the risk of flood in their home — which are useful for considering in risk-mitigation strategies.

The researchers combined new data for hazard and flood protection standards with high-resolution exposure projections and aspects of vulnerability from open data sources. Data from 1995 on tangible losses due to flooding of residential housing stock in Europe were used as a baseline, from which future exposure could be calculated.