Dynamics of Link Importance through Normal Conditions, Flood Response, and Recovery

Abstract

As climate change influences flood frequency, transportation damage and disruptions will become more common. Given the network’s expanse and cost of construction, communities’ mitigation efforts should be informed by analyses that span normal conditions and disaster management phases. This paper analyzes road segment criticality in normal, flood response, and recovery phases in Anderson County, South Carolina, considering impacts on emergency services, healthcare, industry, education, recreation, and transit. A 100-year event provides context for analyzing flood impacts to the time-based shortest paths, determined using ArcGIS Pro 3.1.3. Local and secondary roads were especially affected, with rerouting concentrating around the Anderson City area. Blocked road sections identified potentially vulnerable roads, and normalized betweenness centrality metrics identified community dependence on road segments for daily and emergency operations. While the quantity and dispersion of parks and grocery stores mitigated rerouting distance, other purposes faced challenges from impassable routes. The analysis revealed the southeastern and southern regions as most impacted across purposes, suggesting targeted mitigation. I-85, State Routes 28 and 81, and Federal Routes 29, 76, and 178 were the most critical roads before, during, and after the flood. This study highlights commonalities in road criticality across phases to support resilient transportation planning and sustainability.