A Hybrid Approach for the Assessment of Flood Vulnerability of Historic Constructions and Their Contents

Flooding is among the natural hazards that cause the most significant damage to immovable and movable cultural heritage assets worldwide. Simplified flood vulnerability assessment methodologies are practical tools that can support decision-making strategies to address potential flood damage in cultural heritage assets. However, existing flood vulnerability assessment approaches tailored for cultural heritage are scarce or tend to have significant limitations. Therefore, this paper proposes a new simplified framework for the flood vulnerability and risk assessment of historic buildings using a hybrid approach that combines a baseline vulnerability curve with an indicator-based method, which was defined through an in-depth literature review. The baseline vulnerability curve expresses the potential maximum damage of the historic building as a function of water depth, and accounts for flood vulnerability parameters that reflect the geometric properties of the historic building and the location of the cultural content (e.g., the height of the building, the height and location of the artwork, the existence of underground levels, the distance between the external ground level and the ground floor level). Subsequently, the vulnerability curve is adjusted using a vulnerability index, which has eighteen flood vulnerability indicators categorised into four groups, to establish the resulting vulnerability curve that provides a relative measure of the expected physical damage of the historic buildings due to floods of different intensities. The paper illustrates the methodology through an application to a historic Portuguese building exposed to floods.