In the last 5 years in France, we have observed that each new flood event exposes the weaknesses of the existing prevention system as well as the local weakness. Such events raise questions about the relevance and the effectiveness of the means of prevention. But these events also reveal resistance of the exposed territories, which shows that effective and adequate local strategies exist. There are various methods to evaluate the weakness, or vulnerability of an area, but since the last ten years the qualitative approach of vulnerability in flood risks became more important. Nevertheless, local authorities are often unable to evaluate the vulnerabilities of their territory. Local decision makers request tools for a better assessment of flooding vulnerability. Thus, many approaches of the weakness and the resistance of frequently flooded territories were developed on various scales. These approaches are often partial and contextual. There is a clear need for a support of the evaluation of vulnerability. However, there are obvious synergies between these different approaches, with regard to data retrieval and the establishment of adequate information systems taking into account the vulnerability of a specific territory. The paper develops a methodology aimed to organize into a software tool the choice of vulnerability indicators and the integration of the point of view of various stakeholders (economists, town planners, experts, political leaders, etc). This challenge is based on three simple statements: break down of the problems of vulnerability into homogeneous subsets and manage them; articulation of these subsets in a graphical interface allowing the presentation of interactions between the indicators of vulnerability and compare the opposed visions of vulnerability. The interface of the tool integrates various vulnerability indicators, which are organised in several categories, in order to allow a flexible and efficient vulnerability analysis.

La vulnérabilité et la résilience sont deux concepts qui ont émergé dans des domaines différents et sont utilisés actuellement pour analyser et caractériser les risques. La notion de vulnérabilité constituait le paradigme dominant dans la caractérisation du risque et l’analyse des cyndiniques. Depuis les années 2000, la résilience est mobilisée plus fréquemment en géographie et en urbanisme notamment car le concept de vulnérabilité montre ses limites dans la compréhension des risques. Pour exister, la notion de résilience a évolué. Elle s’impose aujourd’hui comme une notion majeure dans l’analyse des risques. L’objectif de cet article est de comprendre comment le glissement sémantique s’est opéré entre vulnérabilité et résilience. A partir de l’analyse de bases de données, nous montrons que l’usage du terme de résilience est limité jusqu’au milieu des années 2000 puis se développe rapidement. Ensuite, nous tentons de proposer des hypothèses qui pourraient expliquer l’apparition et le développement rapide de la résilience. Enfin, nous essayerons de montrer le risque d’instrumentalisation du concept de résilience par les acteurs de l’aménagement.

This paper deals with the failure risk of masonry constructions under the effect of floods. It is developed within a probabilistic framework, with loads and resistances considered as random variables. Two complementary approaches have been investigated for this purpose: – a global approach based on combined effects of several governing parameters with individual weighted contribution (material quality and geometry, presence and distance between columns, beams, openings, resistance of the soil and its slope. . .), – and a reliability method using the failure mechanism of masonry walls standing out-plane pressure. The evolution of the probability of failure of masonry constructions according to the flood water level is analysed. The analysis of different failure probability scenarios for masonry walls is conducted to calibrate the influence of each "vulnerability governing parameter" in the global approach that is widely used in risk assessment at the urban or regional scale. The global methodology is implemented in a GIS that provides the spatial distribution of damage risk for different flood scenarios. A real case is considered for the simulations, i.e. Cheffes sur Sarthe (France), for which the observed river discharge, the hydraulic load according to the Digital Terrain Model, and the structural resistance are considered as random variables. The damage probability values provided by both approaches are compared. Discussions are also developed about reduction and mitigation of the flood disaster at various scales (set of structures, city, region) as well as resilience.

On‐going changes in cities caused by rapid urbanisation and climate change have increased both the flood probability and the severity of flooding. Consequently, there is a need for all cities to adapt to climate and socio‐economic changes by developing new strategies for flood risk management. The following risk paradigm shifts from traditional to more integrated approaches, since one of the main emerging tasks for city managers is the development of resilient cities. The concept of resilience is becoming more and more important, despite the many challenges that interfere with its implementation. The goal of this research is to create knowledge on how to operationalise flood resilience at the neighbourhood level through neighbourhood design. A research approach was used and a qualitative analysis tool, the DS3 model, was developed in order to study a particular neighbourhood of HafenCity, in Hamburg. Results show that design measures involving transportation infrastructure, land use (open public spaces) and buildings have been the main contributions to the flood resilience of the neighbourhood.

Recent changes in cities and their environments, caused by rapid urbanisation and climate change, have increased both flood probability and the severity of flooding. Consequently, there is a need for all cities to adapt to climate and socio-economic changes by developing new strategies for flood risk management. Following a risk paradigm shift from traditional to more integrated approaches, and considering the uncertainties of future urban development, one of the main emerging tasks for city managers becomes the development of resilient cities. However, the meaning of the resilience concept and its operability is still not clear. The goal of this research is to study how urban engineering and design disciplines can improve resilience to floods in urban neighbourhoods. This paper presents the conceptual Spatial Decision Support System (DS3) model which we consider a relevant tool to analyse and then implement resilience into neighbourhood design. Using this model, we analyse and discuss alternative stormwater management options at the neighbourhood scale in two specific areas: Rotterdam and New Orleans. The results obtained demonstrate that the DS3 model confirmed in its framework analysis that stormwater management systems can positively contribute to the improved flood resilience of a neighbourhood.

Urbanisation and climate change have increased both the probability and the severity of flooding. The risk paradigm that follows shifts from traditional to more integrated approaches, since one of the main tasks emerging for flood managers is the development of resilient cities. The concept of urban resilience is becoming more and more important, despite the numerous challenges that interfere with its implementation. The goal of this research is to study how engineering and other design disciplines can improve flood resilience on an urban neighbourhood scale. This paper presents the analysis of an overview of research aimed at operationalising urban resilience to floods. This literature highlights the fact that almost no references can be found concerning studies focused on operationalising flood resilience at the neighbourhood level and particularly through urban design practices. Indeed, through interviews conducted with several stakeholders, it was confirmed that clear cooperation between flood resilience and urban design practices at the neighbourhood level does not yet exist.