Fleet routing and scheduling in bushfire emergency evacuation: A regional case study of the Black Saturday bushfires in Australia

Abstract

Evacuation planning provides evidence base for effective decision-making in various aspects of disaster response, such as the selection of safe shelters, dynamic assignment of rescue vehicles, and the identification of safest routes and vehicle scheduling. However, an efficient emergency service response to a short-notice bushfire evacuation is a complicated procedure. Any failure to response promptly to short notice evacuation can adversely affect the effectiveness of operations and hence potentially contribute to increased fatalities. This study develops a Vehicle Routing Problem (VRP) model to enhance the efficiency and effectiveness of short-notice emergency response and rescue operations. This model computes the required number of vehicles and identifies the safest routes and schedules for late evacuees under various time windows and road disruption risk. A heuristic solution method is developed to tackle this highly complex nature of VRP due to operational interdependencies. The model parameters are realistically derived from the 2009 Black Saturday bushfires in Victoria, Australia. The results indicate the feasibility of evacuating 1100 late evacuees via low risk routes within the available resources of four shelters and seven rescue vehicles. However, the evacuation of late evacuees from the bushfire affected areas to safe shelters could be potentially affected when the hard constraints such as the time-window are changed. Nevertheless, the model outputs are useful in the development of emergency evacuation plans to mitigate the potential risk of fatality or injury during a bushfire.