Assessing road network risk performance in the United States: A standardized spatial risk analysis

Natural hazards can disrupt road networks, daily activities, and disaster response capabilities, making identifying high-risk areas essential for effective preparedness and response planning. Although existing research addresses road network performance risks, it offers limited insights into spatial patterns, their impact on network functionality, and their implications for disaster operations management. This paper introduces a method to evaluate road network performance risk for various natural hazards at three levels: local (node-specific analysis), regional (risk clustering based on network directions), and global (using a Standardized Spatial Risk Index). The local level considers network topology, historical hazard data, and socio-economic characteristics of the population. The regional level groups local risks by geographic orientation, while the global level assesses the overall spatial distribution of risks across the network. The paper implements the method in the United States, leveraging FEMA's National Risk Index to analyze multiple cities in California and assess risks from 18 types of natural hazards. The results highlight whether an entire city or specific areas require attention, offering actionable insights to enhance resilience through improved mitigation, preparedness, and response strategies.