Large-Scale Zone-Based Evacuation Planning: Models, Algorithms, and Evaluation

In zone-based evacuation planning, the region to evacuate is divided into zones and each zone must be assigned a path to safety and departure times along the path. Zone-based evacuations are highly desirable in practice because they allow emergency services to communicate evacuation orders and to control the evacuation more accurately. Zone-based evacuations may also be combined with contraflows (to maximize the network capacities) and may impose additional constraints on the evacuation path (e,g,. path convergence) and the departure times (e.g., non-preemption). This paper presents a systematic study large-scale zone-based evacuation planning, both from an effectiveness and a computational standpoint. It reviews existing optimization algorithms, and presents new ones, and evaluates them, on a real, large-scale case study, both from a macroscopic standpoint and through microscopic simulations under a variety of assumptions. The results provide some unique perspectives on the strengths and weaknesses of each approach and the implications of evacuation functionalities. The paper also suggests new directions for future research in zone-based evacuation and beyond in order to address the fundamental challenges by emergency services around the world.