Application of Transit Signal Priority for No-Notice Urban Evacuation

Abstract

During an urban evacuation, is it advisable for regional planners to allow transit buses signal priority in cases where police-assisted traffic controls are not an option? With only a finite number of available units, buses will be required to make multiple trips in and out of evacuation zones. Therefore, it is within reason that some regional municipalities would want to allow transit priority to hasten trips made by buses. However, studies in the past have shown that, during times of high roadway demand, transit priority causes major delays for vehicular traffic. The goal of this paper is to examine and quantify the benefit of transit signal priority will have on transit vehicles and any hindrance this priority has on nontransit evacuees. By applying state-of-the-art tools in evacuation modeling and microscopic traffic simulation, the aspects of a multimodel evacuation and transit signal priority impact study are merged within a single study of Washington, DC. On the basis of simulation results, transit signal priority has the potential to save lives by reducing bus travel time by 26%. This signifies that three prioritized buses can handle the workload of four nonprioritized buses. Furthermore, this priority has no adverse effect on the evacuation clearance time of nontransit evacuees. On the basis of this study, transit priority in a multimodal evacuation should be used.