Casualty risks in the discussion on new flood protection standards in The Netherlands

The flood risk management policy in The Netherlands focuses on flood prevention. The current safety standards for the flood defences were developed in the 1960s in response to the flood disaster of 1953. Because The Netherlands has changed drastically since the 1960s, the government decided to reconsider the safety standards. In preparation for a new set of standards for flood protection, cost benefit analyses and casualty risk assessments are carried out. The explicit consideration of casualty risks is a new aspect in the flood risk management policy in The Netherlands. Casualty risk can be assessed from an individual point of view or from a societal perspective. Individual casualty risk is related to a person's probability to die in a flood. It may be a useful indicator to measure whether a base level of protection for everyone is provided. Societal casualty risk, or group risk, is related to the probability of many casualties caused by the same event. Both viewpoints are considered relevant for discussion on future flood protection standards. The paper discusses the background of casualty risks, and their analysis and assessment in the context of deriving adequate flood protection standards.