Journal of Flood Risk Management

Abstract

The Journal of Flood Risk Management takes an interdisciplinary approach to the problems of flooding. Thus flooding is seen as not merely a physical phenomenon but one that incorporates the people and organizations that influence or are subject to flooding and its impacts. By the same token, the potential responses to flood risks include measures to reduce vulnerability to flooding and to minimise the impacts of flood events when they occur, through warning and evacuation for example, as well as measures to reduce the probability of flooding. This integrated approach is now well recognised among flood risk managers and is increasingly being incorporated into national policy. The editorial by Paul Samuels in the previous issue of this journal described the European Directive on the Assessment and Management of Flood Risk, which will lead to the development of flood risk management plans across the European Union in the coming years. Last month I had the pleasure of joining colleagues from the US Army Corps of Engineers, the Federal Emergency Management Agency, the Association of State Floodplain Managers and the National Association of Flood and Storm Water Management Agencies, in discussions about the future direction of flood risk management in the United States. There is a growing consensus about the challenges presented by climate change and intensifying socio-economic change. Having already made the major step towards quantified risk assessment as the basis for rational flood risk management around the globe, a further leap is needed now to translate these methodologies into a future in which ‘stationarity is dead’ (Milly et al., 2008). The magnitude of the future challenge in flood risk management is substantial. Global insurance losses due to flooding are escalating. The UK Foresight Future Flooding project (Evans et al., 2004) calculated the potential for a 20-fold increase in annual average damages in the United Kingdom by the 2080s if flood risk management policy were to remain as it is at present. Different countries are responding to these challenges in different ways. The Dutch Deltacommissie recommended, in its report last month (http://www.deltacommissie.com/en/advies), a 10-fold improvement by 2050 to the already high standards of flood protection in the Netherlands. Although the risks of flooding and socio-economic context vary from country to country, this surely sets a benchmark against which citizens at risk from flooding around the world will compare their own situation. The recent OECD study (Nicholls et al., 2008) on the risks of sea level rise in port cities estimated the scale of the growing challenge of coastal flooding worldwide, and showed that some major cities even in rich countries will have a remarkably high probability of flooding. The integrated approach to flood risk management however recognises that reducing the probability of flooding is only one side of the coin. On the other side is the complex task of reducing vulnerability. This task is complex because of the variety of actors, both public and private, involved in decisions regarding land use and the built environment. There is little consensus upon the most effective means of risk communication with floodplain dwellers. In the governance of communities, responding to flood risk needs to be considered alongside a host of other factors not related to flooding. While flooding is distinctive in many respects, building capacity to deal with flood events may be best thought of in terms of multipurpose resilience to natural and man-made hazards in general. If communities are to be reconfigured to be less vulnerable to flooding, and in certain instances this may involve wholesale retreat from the floodplain when the frequency of flooding or evacuation becomes intolerable, then surely the settlements they move to should be designed to be both resilient to natural hazards and sustainable in a much broader sense. It is clear that many of our cities need to be reconfigured to cope with the pressures of global change from increasing population and resource scarcity, including water scarcity and increasingly costly energy. There are countless trade-offs and interactions as we think though what sustainable communities might look like. From the point of view of energy use, denser cities are much more efficient, and they are also more cost-effective to protect from external flooding, but they may not be optimal from the point of view of internal flooding, which favours open spaces for flood water detention and infiltration. We are only now beginning to understand and simulate these interactions. For example, a next generation integrated assessment model under development at the Tyndall Centre for Climate Change research (http://www. tyndall.ac.uk/research/programme6/results.htm) simulates the interactions between socio-economics, land use, transport, resource flows and climate impacts in urban areas. This provides a means of testing alternative adaptation and mitigation options from a multipurpose point of view, and of designing the transition to sustainability.