Megaregion Network Simulation for Evacuation Analysis

This paper describes a project to develop a microlevel traffic simulation for a megaregion. To accomplish that goal, a mass evacuation event was modeled with a traffic demand generation process that created a spatial and temporal distribution of departure times, origins, and destinations based on past hurricane scenarios. A megaregion-scale simulation was required to assess this event, because only at this level could traffic from multiple cities, over several days, with route assignments in multiple and overlapping directions be analyzed. One finding of the research was that it was possible to scale up and adapt existing models to reflect a simultaneous multicity evacuation covering a megaregion. The movements generated by the demand and operational models were logical and meaningful, and they were able to capture the key elements of the system, including the traffic progression over vast spaces and long time durations. They were also adequate to demonstrate the benefits of proactive traffic management strategies and the effect of increased and decreased advance warning times. The project also revealed numerous limitations of the existing modeling and computational processing capabilities. The knowledge and results gained from this research can be adapted and can be transferable for the evaluation of other locations with different road networks, populations, transportation resources, and hazard threats. Models such as this can also be modified to represent future anticipated growth and development in other large regions and can be used to evaluate the performance, varying conditions, and interrelationships between behavioral response and regional transportation management strategies.