Methodology for Reducing Vulnerability to Flooding in Residential Properties (PAP014811)

Código

PAP014811

Autores

Sarah Lindbergh, Freddy Vinet, Frédéric Leone, Luiz Carlos Salgueiro Donato Bacelar

Tema

Urban Floods

Resumo

Throughout history frameworks of structural and non-structural strategies have been developed to reduce flood damages. In urban environments where a high complexity of assets is at stake, only an integrated application of these strategies will cope appropriately with flood risk. In developing countries a common tendency has been to adopt hazard centered strategies to cope with urban floods. The main objective is to apply structural measures such as construction of dams, levees and reservoirs to stop asset destruction from overflowing waters. Keeping people away from flood-prone areas, another well established strategy, mainly involves flood forecasting and proper land-use planning and policy. Total flood protection is unrealistic. An alternative approach is the acceptance of flooding conditions by reducing the impact of flooding and promoting a fast return to normality after the flood event. Reducing a house's vulnerability to flooding integrates structural and non-structural measures that locally improve quality of life and induce bottom-up processes in flood mitigation. In Haute-Loire (France) a methodology has been developed to identify and propound floodproof measures in residential properties. After measuring in loco the highest level of flooding observed and diagnosing individual residences, technical or organizational floodproofing solutions are presented to every house-hold. The main objective is to assure human safety in the residential environment suggesting specific measures such as the creation of a "refuge space" (balcony or a roof window). This methodology also brings forward measures that will limit flood damage and promote fast return to normality by dry-floodproofing or wet-floodproofing the building with simple architectural adaptations like using waterproof material on the floor and first meters of the wall, elevating the electrical network or installing a cofferdam on the house's main entries. Four major axes are established in this methodology; identifying structural vulnerabilities of the building, defining the technical and social-economic feasibility (operability) of applying the suggested flood mitigating measures, and the social acceptability of these measures. These axes are studied through flood susceptibility maps with return period information, local diagnosis of every residence and questionnaires applied to members of the house hold. Identifying structural vulnerabilities or the sensitive points of the building, gives us the orientation in relation to flood flow, types of construction material, water and electrical network structure, location of water sensitive equipment, etc). With a precise vulnerability diagnosis a definition of proper specific adaptations are listed and their technical feasibility tested. Finally, the acceptability of the residents as well as the social-economic feasibility of the mitigating measures are approached through questionnaires.