Site-Oriented Surrogate Modeling Approach for Flood Risk Assessment: A Case Study of Cultural Heritage Sites in Shanghai

Efficient and accurate flood risk assessment is essential for cultural heritage conservation in the context of increasingly frequent extreme weather events. Conventional flood risk assessment methods primarily aim to approximate inundation patterns across the entire study area, and their analytical units are not necessarily aligned with object-oriented decision-making. To address this limitation, this study develops a site-oriented surrogate modeling approach. The approach integrates site-specific characteristics with multi-scale neighborhood features to characterize local environmental constraints and investigates how neighborhood scale influences predictive performance. To this end, five models are constructed and compared, i.e., M1_Site, M2_50m, M3_200m, M4_500m, and M5_Multi-Scale. Experiments were conducted on 714 cultural heritage sites in Shanghai. Overall, the M2_50m, M3_200m, and M5_Multi-Scale models demonstrate strong predictive performance, with Test F1, GroupKFold F1, and Test Accuracy all above 0.85. According to the results, the site-oriented surrogate modeling approach is feasible, and neighborhood features are important. Model performances also exhibited clear scale sensitivity. This approach provides a practical framework for rapid, site-specific flood risk assessment and offers new insights for decision-making in cultural heritage conservation. Future research could focus on validating this approach in other contexts and applying it to multi-scenario risk analyses to further support heritage conservation planning.