Individual Flood Risk Adaptation in Germany: Exploring the Role of Different Types of Flooding

Abstract. Whether and how flood-affected people prepare for flooding is commonly assumed to depend on their perception of the risk, coping options, and responsibilities. Furthermore, the influence of different flood types, i.e., fluvial, flash, and urban pluvial floods, is unclear, but might be relevant for effective risk communication. Up to now, risk communication has mainly addressed fluvial flooding situations. We use survey data from more than 3000 households affected by different types of flooding in Germany to investigate the influence of flood type on adaptive behaviour in addition to other influencing factors. We use descriptive statistics, Kruskal-Wallis tests, and single-factor ANOVA to identify differences and similarities between respondents. We use linear regressions to identify factors that influence households’ adaptive behaviour in the context of fluvial, pluvial, and flash flooding.

We found that most respondents were motivated to protect themselves, but that there were flood type-specific differences in the factors influencing an adaptive response. For example, those affected by fluvial events had most often implemented measures before the last flooding and had experienced flooding before, but frequently showed signs of emotional coping and were less likely to implement (more) measures. In contrast, those affected by flash flooding showed less confidence in the effectiveness of measures, but were less likely to rate their costs as too high and were most likely to implement measures after the event. We argue that, inter alia, the severity of the flood processes, the experiences of previous flooding, and the management of flooding all shape adaptive behaviour. Regardless of the type of flooding, the perception of the effectiveness of adaptive measures and a positive perception of personal responsibility were found to be crucial for motivating those affected to protect themselves. Further analyses suggest that these two key elements can be strengthened by offering financial support for adaptive measures. We also found that communication on a municipality level enhances residents’ sense of personal responsibility. We conclude that communication and management strategies need to involve municipalities and should be tailored to the locally relevant flood type.