Prioritizing risk for cultural heritage through social value: a participatory framework

Evaluating exposure to natural hazards is crucial for risk management, particularly for cultural heritage, where multi-faceted values like social, aesthetic, spiritual, and historical dimensions make assessment complex. This study presents a participatory, quantitative approach to evaluate the social value of cultural heritage buildings based on a pairwise comparison survey administered to a community of citizens. Moreover, the correlation between social value and other simple proxies is explored. The intangible impact is defined as a combination of social value and a physical property typical of the natural hazard considered, e.g., water depth for floods. The method is applied to the art city of Florence (Italy) where a community of interest joined the survey. The results show that museums are assigned significantly higher social values than places of worship, with UNESCO-listed heritage valued up to 30 times higher than nationally listed buildings. Social value correlates most strongly with ticket price (Spearman's r = 0.68), followed by number of visitors. Canonical correlation analysis links social value more strongly to a combination of variables (r = 0.75), with ticket price and museum status as the most influential factors. Mapping flood magnitude weighted by social value shifts the most at risk areas away from the river, underscoring the importance of intangible cultural values in risk prioritization.