A spatio-temporel optimization model for the evacuation of the population exposed to natural disasters

Abstract

Abstract. The importance of managing the crisis caused by natural disasters, and especially by flood, requires the development of an effective evacuation systems. An effective evacuation system must take into account certain constraints, including those related to network traffic, accessibility, human resources and material equipment (vehicles, collecting points, etc.). The main objective of this work is to provide assistance to technical services and rescue forces in terms of accessibility by offering itineraries relating to rescue and evacuation of people and property. We consider in this paper the evacuation of an urban area of medium size exposed to the hazard of flood. In case of inundation, most people will be evacuated using their own vehicles. Two evacuation types are addressed in this paper, (1) a preventive evacuation based on a flood forecasting system and (2) an evacuation during the disaster based on flooding scenarios. The two study sites on which the evacuation model developed is applied are the valley of Tours (Fr, 37) which is protected by a set of dikes (preventive evacuation) and the valley of Gien (Fr, 45) which benefits of a low rate of flooding (evacuation before and during the disaster). Our goal is to construct, for each of these two sites, a chronological evacuation plan i.e. computing for each individual the departure date and the path to reach the assembly point (also called shelter) associated according to a priorities list established for this purpose. Evacuation plan must avoid the congestion on the road network. Here we present a Spatio-Temporal Optimization Model (STOM) dedicated to the evacuation of the population exposed to natural disasters and more specifically to flood risk.