An assessment framework of dam-break flood risk in highly populated and property-intensive area: Case study for the Longdong reservoir

Abstract

Study region: Longdong Reservoir and downstream flood-prone region in Guangzhou, China Study focus: Severe flooding generated by a dam-break event in urban area would cause huge damages to social economy such as industrial production and commercial trade. The damage degree would vary when it happens in different time, due to the population distribution changes over time for the daily production and life. Investigating dynamic assessment method for dam-break flood risk is significant for disaster mitigation. In this study, a framework integrating a hydrodynamic model and set pair analysis were utilized to the study area. Population dynamics was characterized by utilizing time-varying population heat maps as a vulnerability index. The points of interest and nighttime light datasets were also applied to quantify some exposure and vulnerability indices. To establish a hierarchy of the most important parameters with respect to hazard, exposure, and vulnerability indices, using game theory to balance the subjective and objective hierarchies derived from the analytic hierarchy process and criteria importance through intercriteria correlation methods. New hydrological insights for the region: The proposed framework effectively integrates population distribution changes and flooding characteristics, and can accurately characterize the evolutions of dam-break flood risks at different time. This framework offers significant insights and robust technical support for flood prevention and material relief management when encounter the disaster of dam-break event.

Keywords

• Risk assessment framework
• Dam-break flood
• Multi-source dataset
• Set pair analysis
• Game theory