Urban Lifeline Resilience under Compound Hazards: A review on the cascading failures and systemic risk

Core infrastructure systems like water, electricity, transport, and communication are fundamental to modern cities, supporting vital services and everyday societal operations. However, their resilience is increasingly threatened by the occurrence and severity of compound hazards, such as floods that occurs concurrently with power system outages. These risks increase systemic risks that go far beyond the original source of disruption and frequently cause cascade failures throughout interconnected networks. With an emphasis on the dynamics of interdependencies and cascading consequences, this study investigates the resilience of urban lifeline networks under compound hazard situations. To capture the multi-layered vulnerabilities of lifeline systems, the study combines functional dependencies, performance indicators, and hazard scenarios using a network-based modelling technique. The results demonstrate how interruptions in one industry may quickly spread to others, worsening service outages and impairing emergency response capabilities. Key resilience measures—robustness, redundancy, and recovery time—are evaluated to identify vulnerable nodes and routes under compound hazards. The paper also explores mitigation strategies such as advanced monitoring, decentralized energy systems, and adaptive infrastructure design. By linking hazard modelling with resilience assessment, the study advances knowledge and offers practical insights for policymakers and engineers to strengthen urban lifeline resilience. This review uniquely synthesizes recent advances in understanding the interdependencies and cascading dynamics of urban lifeline systems exposed to compound hazards. It provides a comprehensive framework that integrates systemic risk concepts with resilience assessment approaches, offering new insights for urban resilience research and practice. This review contributes to the current body of knowledge by synthesizing existing research on cascading failures and systemic risks affecting urban lifeline systems under compound hazards, and by proposing a conceptual framework to enhance urban resilience planning and risk-informed decision-making.