GIS and hybrid multi-criteria decision analysis based urban flood risk assessment in Hanchuan City, Hubei Province, China

The risk mapping of flood-prone areas enables the visualization of disaster risks, which can serve as a basis for the development of disaster mitigation strategies. This study presents a new hybrid multi-criteria decision analysis method that combines geographic information systems in Hanchuan City, integrating multidisciplinary fields to develop a more systematic and accurate assessment method. We selected 19 factors to create models for hazard, sensitivity, vulnerability, and disaster prevention. For the first time, a vulnerability model considered the impacts of population, economy, housing, and crops to optimize the indicator system. This model calculated weights using the improved analytic hierarchy process based on the cloud model, combined the entropy weighting method and game theory, and applied ArcGIS 10.8 to generate a risk map. The model results were validated using historical disaster sites, with an accuracy of up to 92%. The results indicate that the annual waterlogging index in the hazard model, land use in the sensitivity model, population and GDP in the vulnerability model, and shelter capacity in the disaster prevention model had larger weights and were closely related to meteorological, hydrological, and emergency responses. Approximately 17.55% of the study area falls within the high-risk zone, while 35.10% classified as medium–high risk is concentrated in the east-central region of the Han River. This risk assessment will serve as a basis for urban emergency policies, helping similar urban areas realize sustainable development strategies.