Simulating Wildfire Evacuation in Wildland-Urban Interface Communities with Transient Populations

Wildfire poses a significant threat to life and property in the western United States. When a fire approaches a community and becomes a threat to residents, emergency managers need to consider both fire behavior and the expected response of the threatened population to warnings before issuing protective action recommendations to residents at risk. In wildfire evacuation practice, incident commanders typically implement either staged or simultaneous evacuation strategies. This dissertation examines the effectiveness of staged evacuation in wildland–urban interface (WUI) resort communities with transient populations by integrating traffic simulation and fire spread modeling.This dissertation is composed of three manuscripts that build sequentially upon one another. The first manuscript develops a staged wildfire evacuation model using Java and the Multi-Agent Transport Simulation Toolkit (MATSim). Comparisons of staged and simultaneous evacuation scenarios demonstrate that staged evacuation reduces traffic congestion near the fire front, thereby limiting evacuees' exposure to wildfire hazards. The second manuscript couples the traffic simulation model with the Fire Area Simulator (FARSITE) and introduces a zone-based egress assignment method. A linear algorithm distributes evacuation demand among multiple egresses while minimizing the sum of the relative network clearance times for predefined evacuation zones. Compared with an agent-based method that assigns each vehicle to its nearest egress, the zone-based method reduces evacuation traffic near the fire front and produces lower estimated evacuation times (ETEs). The third manuscript presents the Wildfire Evacuation Simulation Toolkit (WEST), a web-based platform that integrates wildfire spread and traffic simulation models for communities with transient populations. The platform uses a service-oriented architecture (SOA) and Open Geospatial Consortium (OGC) standards to deploy simulation models and computational tools as web services. Its graphical user interface (GUI) enables evacuation researchers, emergency managers, and community planners to configure scenarios, run simulations, and evaluate evacuation strategies. Together, the manuscripts establish an integrated staged-evacuation framework. The findings indicate that staged evacuation and zone-based egress assignment improve evacuation performance by reducing traffic near the fire front, balancing demand across available egresses, and lowering ETEs.