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TUE7.8: Flood risks
Causes that make developing countries more vulnerable in disasters in the case of flooding
Tehran University, Iran, Islamic Republic of
All over the word, especially in developing countries, population growth with increasing urbanization rate, especially around the cities, is considered as potential risk. These areas have dense population and wide spread economic activities that are more vulnerable to damages from natural disasters. Because of the inappropriate utilization of water resources, inappropriate soil and vegetation conservation and cities development without planning, these areas are more exposure to flood. Paying attention to prevention phase can play a determinant role in reducing flood risk. Applying a series of instructions for building reinforcing and flood management in urban areas can dramatically reduce floods effect.
Amphibious houses and fiscal incentives: revitalizing local economies of flood-prone areas
CO2 Bambu, Nicaragua, Republic of
The increasing awareness of vulnerability to flooding events of certain regions, municipalities or neighborhoods is leading to a pattern of reduced investment by private sector actors. Whether as a result of inability to get building permits, or self “deselection” for investment in flood-prone zones, the result is a self-fulfilling cycle of de-investment, thus loss of business activity and loss of tax receipt for these municipalities. Therefore a multitude of short run investment decisions can lead to longer-run impoverishment of certain communities. This can be reversed through fiscal incentives given to home owners, as well as a radical shift in permitting in flood-prone areas, specifically for amphibious housing solutions. Amphibious houses are houses that sit on the ground for most of their lives, but which can rise with water levels during a flooding event, and then return to the ground once the water level subsides. The Netherlands has a long history of battling sea levels and has grown a domestic industry of amphibious structures architects and builders. After Hurricane Katrina, amphibious building solutions have started to be experimented with in Louisiana and has demonstrated the technical feasibility of building homes, in fact potentially entire neighborhoods with amphibious housing. A proactive set of tax incentives for amphibious housing and business offices could go a long way toward breaking the paradigm of avoidance of flood-prone areas, and in fact could spur entire new local economies of flood resilient neighborhoods, revitalizing zones that are destined for an economic death spiral for these municipalities.
Reframing risk- and responsibility-sharing in flood risk management in England and Austria
Flood Hazard Research Centre, Middlesex University, United Kingdom
Flood governance and policy in Europe are changing: the role of the state and individual responsibility for risk management are now key contemporary issues in flood policy. The new policy agenda is to enhance the responsibilities of local authorities and individuals in flood risk management and reduce the controlling role of central national governments. In this way, the focus of policy discussion refers two main aspects: (a) fair sharing of risk-burdens between public authorities, private companies, and individuals and (b) process of sharing responsibility, especially how to encourage lower government agencies and non-government agents to take over certain tasks from the central government. In general, risk- and responsibility-sharing comprises new governance practices, which include new regulations, organisations and institutions. Main problems can be (1) only a (re-)imagination process of fair sharing of risk burdens, (2) shadow of more democratic processes, (3) shadow of hierarchy and balance of power between the different stakeholder groups as well as (4) ‚hollowing out‘ the state. This paper examines partnership approaches for flood risk management in Austria and England. First results show that these partnership approaches develop in direct relation to recent major flood frequency and recent flood history as well as recent financial crises. The current functions of a partnership approach in flood risk prevention lie within the selection of sites for retention basins, conservation of regionally important retention areas, harmonising emergency and spatial planning instruments and awareness-raising for protective measures on a regional level. An important issue is that of compensation measures between upstream and downstream communities, which at present is causing many conflicts. I conclude that although a partnership approach may be seen as an ‘optimal’ solution for flood risk management, in practice there are many limitations and barriers in establishing these collaborations and making them effective (especially in the long term).
Precautionary evacuation operations using decision analysis: application to catastrophic flood event
1University of Manchester, United Kingdom; 2Warwick University, United Kingdom
Catastrophic disaster represents a vital issue for many countries in the European Union (EU) and around the world. Given the potential damage to human lives that hazards represent, evacuation operations can be the only option available to mitigate the loss of life from catastrophic disaster. However, due to the amount of time needed to evacuate a large area, the decision to evacuate must occur when there is a relatively low probability of the event. Decision Analysis (DA) represents a framework through which managers’ preferences can be modelled along with the uncertainties that influence evacuation outcomes. Evacuation decisions were studied in ten different countries to identify specific evacuation criteria for multiple hazards and the uncertainties that affect outcomes of those decisions. A study of storm-tide flooding is then provided to identify levels of risk at which evacuation actions are optimal. This analysis is supported with both sensitivity analysis and Monte Carlo simulation to assess how uncertainty in both the preference and probability structure of the decision influence evacuation decisions. The DA findings are then compared with actual evacuation thresholds to provide insight into actual evacuation planning. The primary risk threshold identified for large-scale flood events was at a likelihood of approximately 10%. The study found that actual evacuation actions were slightly more risk-seeking than the prescriptive DA model. Sensitivity analysis and Monte Carlo simulation also found that evacuation thresholds were highly influenced by non-evacuee casualty rates and emergency managers’ preference for avoiding flood casualties. Substantively, these results represent a multi-criteria methodology to support operational planning for evacuation in advance of catastrophic hazard events. This process supports pre-hazard preparedness by explicitly structuring the evacuation decision using a multi-criteria structure. It can also be used to communicate evacuation decision-making and guide data gathering to improve government preparedness in advance of disaster.
GERIHCO - An interdisciplinary approach to understand the muddy floods risk (Alsace - France)
1Irstea-GESTE, France; 2LIVE-CNRS, France; 3Lhyges-CNRS, France; 4CRESS, University of Strasbourg, France
The interdisciplinary research program GERIHCO (for “Gestion des Risques et Histoire des Coulées Boueuses - Risk Management and History of Muddy Floods) has started in 2005 with a pool of a dozen researchers interested in the study of the risk of muddy floods in the Alsacian region. Since then, more than 30 researchers from disciplines as different as economy, sociology, geography, agronomy, have been involved in the several workpakages developed during the project. The main issues studied are related to: (1) the comprehension of the physical processes of muddy floods and the potential agronomic measures that can be implementing to decrease the hazard; (2) the economic assessment of a potential implementation of such measures at the farmers’ scales and more generally the way they could accept new economic tools implementing to improve “good” practices decreasing runoff and soil erosion; (3) the risk perception for local actors exposed to the risk of muddy floods (or directly involved in the risk management) and their potential actions to prevent them for future damages. Other issues such as the role of the information and the communication in risk mitigation strategies have been also studied. (4) The sociological issues are related to the understanding of the environmental beliefs intervening in the management of the risk prone areas. The results show that the management of a natural disaster occurring every year in some cases and damaging inhabitants as well as farmers has to be managed with a collaborative approach: all actors have to be involved in the settlement of mitigation measures. The financial support of the local Water Agency allows us to implement the different studies and then to communicate largely the results of the program. This investment also shows the interest of such an approach in risk studies.
Evaluating and improving the railway safety against flood
1tehran university, Iran, Islamic Republic of; 2Assistant professor of Tehran University; 3Clerk of Red Crescent
Railway is one of the most important infrastructures. Safety and maintaining the effectiveness of rail network has an important role in relief and logistic while disasters occur. Disasters especially flood has negative effective on the effectiveness of rail network. Considering the importance of disaster, in this paper, the safety of Iran railway is taken in to consideration. At the end, a number of strategies are suggested to increase the network safety.