Resilience in the mediterranean cities: an example of adaptation and risk reduction working on building types

The relationship between urban settlement and water has always been a challenging subject for urban planners, nowadays it is even a more compelling subject due to the climate change and the increasing number of natural disaster related to floods. Growth and development in every civilization are closely connected to the forms of adaptation used to survive and thrive since ancient times, flood adaptation instead of flood control is one of expedients that allow us to cope with such events using tools that enable to live and flourish in those areas exposed to a constant risk using an approach that takes into consideration both temporal and spatial scale at the same time. In Italy about 45 % of the municipalities are at high hydro-geological risk, his paper, in particular, aims to show how it could be possible to reduce the risk related to flood hazard in an area at the delta of the Tiber river outside Rome, Idroscalo, which has been ranked with the highest degree of flood risk, using innovative building types and a 1-D hydraulic model. We worked on the dataset that the Basin Authority of the Tiber river provided us, with crosssections and set a return time of 200 years to study a reliable scenario of flooding event. The computation of the flood propagation is performed through HEC-RAS (Hydrologic Engineering Centers River Analysis System) ) using the standard 1-D equation of unsteady flow. Due to the informal connotation of the settlement, a hypothesis of restoration project has been taken into account, to provide safety and preserve the high sense of community that inhabitants have developed living in the area for over 50 years. Flood risk is the product of flood hazard, vulnerability and exposure, reducing the amount of damages that could occur to people and their goods with adequate building types such as amphibious and floating, could provide an answer for all the areas where people and hydraulic risk coexist daily. For all those lands considered not suitable for regular buildings but, where informal urbanization has spread out, those kind of construction would represent a solution to dislocations, maintaining the local features, preserving the social community and mitigating the risk at the same time.