Simulation Study of Evacuation Routes and Traffic Management Strategies in Short-Notice Emergency Evacuation

Emergency evacuation traffic is simulated in response to an assumed chlorine gas spill incident in downtown Jackson, Mississippi. The best evacuation corridors are identified, and possible effective traffic management strategies are compared to increase the cumulative number of vehicles evacuated out of the protective action zone and to decrease the average travel times for evacuees. To relieve the heavy traffic congestion around the spill location caused by the sudden increase in demand, traffic management strategies (law enforcement for traffic control, contraflow operations, and variable message signs) are tested on the three major arterial streets in the protective action zone to improve evacuation performance over a baseline traffic management strategy. A multiway analysis of variance was conducted for the simulation results to numerically assess the effect of each factor that might contribute to the performance of the short-notice evacuation. Results of a comparison of evacuation scenarios used to determine evacuation effectiveness and statistical analysis indicated that (a) selection of a best contraflow operation route depends on interference from intersecting links and the cost of deploying traffic management and (b) the use of both contraflow and variable message signs could improve evacuation performance over using neither or only one of the two strategies.