Modelling Community Evacuation Vulnerability Using GIS

We present a method for systematically identifying neighbourhoods that may face transportation diYculties during an evacuation. A classi® cation of this nature oVers a unique approach to assessing community vulnerability in regions subject to fast-moving hazards of uncertain spatial impact (e.g., urban ® restorms and toxic spills on highways) . The approach is founded on an integer programming ( IP) model called the critical cluster model (CCM). An heuristic algorithm is described which is capable of producing eYcient, high-quality solutions to this model in a GIS context. The paper concludes with an application of the method to Santa Barbara, California.