Dynamic Travel Demand for Emergency Evacuation: The Case of Bushfires

Abstract

There are two types of emergencies; those which can be anticipated and those that cannot. Among those that can be anticipated are such events as cyclones, floods, bush fires, and tsunamis. When such events are anticipated, one course of action that may be taken is the evacuation of residents from a threatened area. When evacuation takes place, there often remains a need to provide access for emergency vehicles and personnel to the threatened area creating a conflict between the needs to maximise capacity for evacuation, while continuing to provide access to the threatened area. Relatively little is known about when residents will decide to evacuate. A model of evacuation behaviour is needed that would predict the proportions of the population that would leave within certain time periods, thus leading to the development of an evacuation travel demand model. Under a contract from Emergency Management Australia, the authors developed a method to predict evacuation decisions by residents from bush fires. This paper describes the methods used to determine when a household would evacuate, and describes the resulting model that predicts how many partial and full evacuations will take place by time period from when the emergency is first perceived.