No abstract

This article deals with methods for the estimation of loss of life due to flooding. These methods can be used to assess the flood risks and to identify mitigation strategies. The first part of this article contains a comprehensive review of existing literature. Methods have been developed for different types of floods in different regions. In general these methods relate the loss of life in the flooded area to the flood characteristics and the possibilities for evacuation and shelter. An evaluation showed that many of the existing methods do not take into account all of the most relevant determinants of loss of life and that they are often to a limited extent based on empirical data of historical flood events. In the second part of the article, a new method is proposed for the estimation of loss of life caused by the flooding of low-lying areas protected by flood defences. An estimate of the loss of life due to a flood event can be given based on: (1) information regarding the flood characteristics, (2) an analysis of the exposed population and evacuation, and (3) an estimate of the mortality amongst the exposed population. By analysing empirical information from historical floods, new mortality functions have been developed. These relate the mortality amongst the exposed population to the flood characteristics. Comparison of the outcomes of the proposed method with information from historical flood events shows that it gives an accurate approximation of the number of observed fatalities during these events. The method is applied to assess the consequences for a largescale flooding of the area of South Holland, in the Netherlands. It is estimated that the analysed coastal flood scenario can lead to approximately 3,200 fatalities in this area.

No abstract

This article gives an overview of the research on loss of life due to floods. The limited information regarding this topic is presented and evaluated. Analysis of global data for different flood types shows that the magnitude of mortality is related to the severity of the flood effects and the possibilities for warning and evacuation. Information from historical flood events gives a more detailed insight into the factors that determine mortality for an event, such as flood characteristics and the effectiveness of warning and evacuation. At the individual level, the occurrence of fatalities will be influenced by behaviour and individual vulnerability factors. Existing methods for the estimation of loss of life that have been developed for different types of floods in different regions are briefly discussed. A new method is presented for the estimation of loss of life due to floods of low‐lying areas protected by flood defences. It can be used to analyse the consequences and risks of flooding and thereby provide a basis for risk evaluation and decision‐making. The results of this research can contribute to the development of strategies to prevent and mitigate the loss of life due to floods.

No abstract

No abstract

No abstract

After the catastrophic flooding of New Orleans due to hurricane Katrina, plans have been developed for the improvement of the flood protection system of the city. In this paper, we apply the principles used in the Netherlands for risk‐based design of flood protection systems to the New Orleans metropolitan area. In this so‐called economic optimization, the incremental investments in more safety are balanced with the reduction of the risk to find an optimal level of flood protection. Although the analyses are preliminary and not yet fully realistic, the presented outcomes indicate that for densely populated areas, such as the central parts of New Orleans, it could be justified to choose a higher protection level than the currently proposed level of 1/100 per year. The results of the economic optimization can be considered as technical advice that can be used as input for the (political) decision‐making.