Flood-related fatalities during the flood of July 2021 in North Rhine-Westphalia, Germany: what can be learnt for future flood risk management?

Abstract

During the severe flooding in July 2021 189 people lost their lives in Germany, which is the highest number of flood-related fatalities since 1962. 49 people died in the densely populated state of North Rhine-Westphalia (NRW), whose flood risk management has, however, often been regarded as pioneering in Germany. To further improve flood risk management in NRW, the causes and circumstances of all 49 flood-related deaths were analyzed. Based on official files a structured document analysis was performed and a new coding scheme was developed that relates accident locations and victims’ activities to accident dynamics and causes of death. Circumstances and causes of death differed significantly between in-/outdoor incidents, age groups, and areas with different event magnitudes. Elderly people (>60 years) were particularly at risk; they account for two thirds of the dead. Eight of the 25 people who died in a building were surprised by water entry into basements or ground-floor apartments. In addition, there are indications that nine of 24 people who died outdoors were surprised and caught by water on their way home or when trying to leave the flooded zone. It is assumed that a lack of warning played a role in these cases. In most of the remaining cases, hazards were underestimated pinpointing to insufficient awareness and weaknesses of crisis and risk communication. 14 people died in their basements while attempting to inspect equipment (e.g., pumps) or to inspect, minimize, or repair damage. Since property-level adaptation has been emphasized in flood risk communication, life-threatening situations during fast onset-flooding and the priority to be safe have to be emphasized in future communications. It has to be acknowledged that the official hazard maps indicated no risk from flooding at around half of the 49 accident locations illustrating the exceptional event magnitude. Still, warning levels and flood hazard maps should be better linked to identify hazard zones and to enable appropriate behavior including (self-)evacuation.