Multi-hazard analysis of ground movement – flooding in underground man-mad cavity regions

This paper investigates multi-hazard analysis and the interaction between ground movement hazards and flood hazards in mining regions. The literature review highlights that these two hazards interact through various mechanisms. To address this, the study presents a general multi-hazard approach focused on ground movement–flooding interactions. A five-step methodology was developed to: Identify and characterize each hazard, identify potential interactions, assess the level of interaction between hazards, Adjust the "isolated" hazard level, and calculate the multi-hazard index. The interaction of 11 flood and ground movement hazards was analysed based on expert judgment and interaction tools, including an interaction matrix, interaction loop, and fault tree analysis. The developed methodology was applied and validated in a case study within a municipality exposed to both hazards. Results demonstrate that the interaction between these hazards is significant, as they share common predisposing factors such as depth, water table levels, watercourses, and infrastructure networks. The study emphasizes the necessity of multi-hazard analysis for optimizing natural risk management. This innovative approach offers new opportunities for improving risk mitigation strategies, including optimized treatment solutions and adapted urban planning.