Hurricane evacuation planning using public transportation

Just before a hurricane is predicted to strike an urban area, millions of people evacuate from impact zones to safer regions. This paper provides a mass-evacuation strategy using public transportation before the strike of a hurricane. The assumptions made are that the evacuation zones, shelter locations, and the time of strike of the hurricane are pre-determined. The evacuation operations commence when the warnings are issued and end when the hurricane strike is predicted to occur. We propose a multi-stage approach. At the first stage is the planning framework, where pickup locations are determined and assigned to shelters, and an initial set of routes is generated along these locations. This is done by weighing each location based on the accumulated demand, and favoring multiple routes to pass through a location with higher demand. In the next stage, each route is assigned a trip number such that 1) routes with higher demand require more trips, and 2) two successive trips to a route are spaced evenly. A simulation tool has been developed to model the dispatching of the given number of buses, stochastic arrival of evacuees, queueing effects at the pickup locations, and the transportation of evacuees to the safety regions. The results from the simulation presented in this paper serve as an evaluation tool for a route design, and a local search heuristic is proposed to effect positive changes in the route design.