On the Influence of the Main Floor Layout of Buildings in Economic Flood Risk Assessment: Results from Central Spain

Flood Risk in a Heritage City: Alzira as a Case Study

Floods are natural hazards which have damaged cities and their architectural heritage over the centuries. The heritage town of Alzira (Valencia, Spain) is a major case study for the assessment of flood risk in architectural heritage. Alzira was founded by the Al-Andalus Moors on a river island within a bend of the river Júcar, which has overflowed more than 80 times during its history. The main aim of this work is to analyse the vulnerability to floods of the town’s architectural heritage, especially that of earthen architecture, a constructive tradition of which several examples can be found in the town. The proposed methodology attempts to calculate the vulnerability of the earthen architecture through the evaluation and weighting of extrinsic and intrinsic parameters. This makes it possible to identify the constructive characteristics and material weathering which worsen the behaviour of structures during floods. Maximum vulnerability values have been obtained for poorly conserved constructions without cladding. Results highlight the importance of ascertaining suitable strategies for the prevention and mitigation of risk as future lines of research. The vulnerability assessment methodology presented in this study could be applied to other case studies in other sites with architectural heritage under threat from floods.

Minimal Building Flood Fragility and Loss Function Portfolio for Resilience Analysis at the Community Level

Current flood vulnerability analyses rely on deterministic methods (e.g., stage–damage functions) to quantify resulting damage and losses to the built environment. While such approaches have been used extensively by communities, they do not enable the propagation of uncertainty into a risk- or resilience-informed decision process. In this paper, a method that allows the development of building fragility and building loss functions is articulated and applied to develop an archetype portfolio that can be used to model buildings in a typical community. The typical single-variable flood vulnerability function, normally based on flood depth, is extended to a multi-variate flood vulnerability function, which is a function of both flood depth and flood duration, thereby creating fragility surfaces. The portfolio presented herein consists of 15 building archetypes that can serve to populate a community-level model to predict damage and resulting functionality from a scenario flood event. The prediction of damage and functionality of buildings within a community is the first step in developing risk-informed mitigation decisions to improve community resilience.

Flood Risk Assessments: Applications and Uncertainties

The present Special Issue brought together recent research findings in Flood Risk Assessments (FRA) and contains contributions on advanced techniques and real cases where FRA have been carried out. The 16 research contributions highlight various processes and related topics where FRA have been applied and the main benefits and improved knowledge derived from them, as well as their replicability in other study sites. The published papers can be classified into three major categories. (a) First, there are those papers focused on improving the methods and results of FRA over different scenarios of both flooding types (river flooding or flash flooding) and flooding areas (urban, non-urban, small mountain communities). (b) Second, there are studies that investigate the application of FRA to diverse topics such as “land urban planning” or “vulnerable infrastructure management (dams, power plants)”. (c) Finally, there is a third group of papers which are focused on the assessment of the sources of uncertainties in FRA, with the aim of improving the results and making it more consistent with the real world.