Suchergebnisse

Abstract
Water-related disasters have caused increasing losses in recent years. Efficient risk reduction policies require accurate assessment approaches, with careful consideration of costs, beyond material damages, which are commonly used in practice. Faced with possible risk reduction scenarios, limited financial resources require an improvement in the quality of cost estimation, thereby contributing to an efficient allocation of resources. This paper reviews the concept of total cost in the context of water-related disasters, elaborating on the typical direct/indirect and tangible/intangible cost categories. These categories are defined and explained, supported by a comprehensive assessment of economic valuation methods. Based on this information, practice relevant suggestions are made concerning the most appropriate methods for different cases in terms of scale, availability of data and of technical resources.

Abstract. This article presents a novel methodology to assess flood risk to people by integrating people's vulnerability and ability to cushion hazards through coping and adapting. The proposed approach extends traditional risk assessments beyond material damages; complements quantitative and semi-quantitative data with subjective and local knowledge, improving the use of commonly available information; and produces estimates of model uncertainty by providing probability distributions for all of its outputs. Flood risk to people is modeled using a spatially explicit Bayesian network model calibrated on expert opinion. Risk is assessed in terms of (1) likelihood of non-fatal physical injury, (2) likelihood of post-traumatic stress disorder and (3) likelihood of death. The study area covers the lower part of the Sihl valley (Switzerland) including the city of Zurich. The model is used to estimate the effect of improving an existing early warning system, taking into account the reliability, lead time and scope (i.e., coverage of people reached by the warning). Model results indicate that the potential benefits of an improved early warning in terms of avoided human impacts are particularly relevant in case of a major flood event.