Perigosidade a cheias no rio Uíma (Santa Maria da Feira, Portugal): ensaio metodológico de suporte à implementação da Diretiva 2007/60/CE

• Autor(a) principal: Marafuz, Inês
• Data de Publicação: 2014
• Outros Autores: Adelino, Rui, Gomes, António Alberto
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: https://hdl.handle.net/10216/77556
• topic: Humanidades; Humanities

The increase of fl ood events and consequent human losses and material damages has led to a growing concern among European governments and national authorities. In this context, the adoption of the Directive 2007/60/ CE established the need to perform a preliminary fl ood risk assessment and to produce applied cartography to minimize the effects of these events. This paper presents a methodological essay for the determination of fl ood hazard in the Uíma river sector, north of Portugal, through the application of an intensity-probability matrix. This relates the height of water column and the water velocity parameters, modelled in the Hec-Ras software, with the frequency of occurrence of fl oods. At the end, the exposed elements, namely the built up areas and roads, were identifi ed for each class of danger. The results show that the large differences in the fl ood-prone areas for the return periods considered (10, 50 and 100 years), stands out in the middle of the modelled alluvial plain. The height of water column presents higher values in the segments of the river upstream of the bridges, which act as barriers to the water circulation. The water velocity is high in those segments and in the upstream sector, where the valley is constricted. By the combination of these factors and the recurrence of the events, it appears that the fl ood danger is higher in the sectors crossed by bridges and at the beginning of the modelled sector. The applied methodology aims to be a contribution to the Portuguese municipalities that have to achieve similar results which is presented in this work, in order to fulfi l the requirements stipulated in the Directive.