The effects of climate dynamics on urban areas involve the aggravation of existing conditions and the potential for emergence of new hazards or risk factors. Floods are recognized as a leading source of consequences to society, including disruption of critical functions in urban areas, and to the environment. Consideration of the interplay between services providers ensuring urban functions is essential to deal with climate dynamics and associated risks. Assessment of resilience to multiple hazards requires integrated and multi-sectoral approaches embracing each strategic urban sector and interactions between them. A common limitation resides in the limited data and tools available for undertaking these complex assessments. The paper proposes a methodology to undertake the spatial characterization of the flood related hazards and exposure of both essential functions and services providers in urban areas, in the context of limitations in data and in ready-to-use tools. Results support the resilience assessment of these hazards, taking into account interdependencies and cascading effects. The approach is applied to Lisbon city as the study case. Results are promising in demonstrating the potential of combining data and knowledge from different sources with dual modelling approaches, allowing us to obtain trends on the magnitude of effects of climate scenarios and to assess potential benefits of adaptation strategies. Quantification of the effects is reached, but results need to be assessed together with the underlying levels of uncertainty. The methodology can facilitate dialogue among stakeholders and between different decision levels.

According to the United Nations, by 2030, 60% of the world’s population will live in cities, and 70% by 2050. Both consolidated and fast urbanizing areas face diverse acute shocks from natural disasters and long-term stresses, such as the effects of climate change. Therefore, there is a need for cities to implement plans for increasing resilience and improving preparedness to cope with both acute shocks and long-term stresses. Development of resilience action plans (RAP) constitutes an important process for the cities to plan their resilience enhancement in the long, medium, and short terms. These are key tools for the city, considering the associated complexity, uncertainties, data scarcity, interdependencies among urban services provided in the city, as well as involved stakeholders. Herein, a framework is presented to support city resilience action planning related to climate change through a multisector approach. The framework was applied step by step to three cities—Barcelona, Bristol, and Lisbon—and their RAPs to climate change provide roadmaps for resilience, having the urban water cycle as the core. In these plans, urban services are included, given their interactions and contributions to city’s resilience. Addressed services are water supply, wastewater, storm water, waste, electric energy, and mobility.

Climate trends suggest an increase in the frequency of intense rainfall events and the aggravation of existing conditions in terms of flooding in urban areas. In coastal areas, conditions are aggravated by coexistence with coastal overtopping. Flood risk control is complex, and the interdependencies among the services and sectors in urban areas imply the need for adoption of approaches that embrace the interplay between service providers to ensure critical urban functions. Flooding incorporates several hazards. Assessment of resilience to multiple hazards in complex environments benefits from integrated and multi-sectoral approaches. A common constraint resides in the limited data and tools available for undertaking these complex assessments. This paper proposes a risk-based methodology to assess urban areas’ resilience to flooding by addressing sectors’ interdependencies in a context of limited data and ready-to-use tools. Multisector flood risk identification is pursued with the support of a geographic information system and is applied to Lisbon with a focus on the cascading effects of drainage system failures on buildings, populations, mobility, waste management, and electricity supply. The results demonstrate the potential for combining data and knowledge from different sources with dual modelling approaches, thus allowing one to obtain trends of exposure and vulnerability to flooding for current and climate change scenarios. This methodology facilitates dialogue among stakeholders and decision levels by contributing to capacity building, and it contributes to sustainable development.