Identifying Critical Locations for Traffic Monitoring Devices during Hurricane Evacuations

Large-scale evacuations from natural disasters such as hurricanes pose major logistical and operational challenges. There is often insufficient roadway capacity for entire populations to evacuate immediately, causing costly and potentially deadly delays. Traffic monitoring devices (TMDs) can help ensure an evacuation proceeds smoothly. Information collected by such devices can help authorities direct traffic onto underutilized routes and dispatch emergency services to clear traffic incidents faster. Closely monitoring every roadway in the system is prohibitively expensive, so we propose an efficient quantitative method to identify links that would most benefit the system by being monitored; we define these critical locations as roadway segments where any delay or underutilization of capacity will increase the overall evacuation time. We test this method in two case study hurricane scenarios along the Texas coast, and demonstrate how monitoring these critical locations could reduce delays if the information collected leads to faster incident clearance times and information provided to drivers improves their routing decisions. The simulation indicates that routing decisions have a larger impact on performance than incident detection and that effective traffic monitoring and route guidance can reduce clearance time for a large-scale evacuation in the Houston region by 19.1%.