Subway Service Down Again? Assessing the Effects of Subway Service Interruptions on Local Surface Transit Performance

Cities around the world are keen to offer modern urban transit systems that connect various locations in an efficient and reliable manner with the highest degrees of riders’ experience. These systems may consist of various modes such as buses, streetcars (or trams), and rapid transit systems (e.g., subways). In both research and practice, the quality of transit service has traditionally been measured and investigated on a mode-by-mode basis. Therefore, it is rare to find studies that investigate the impacts of poor performance or breakdown of one transit mode on other functioning modes in multimodal integrated transit systems. This research aims at understanding the impact of subway service interruptions on the speed performance of surface transit in Toronto, Ontario. To do that, a detailed data set of subway service interruptions collected in 2013 by the Toronto Transit Commission (TTC), the public transit provider in the City of Toronto, was used. In addition, another data set was obtained from the TTC’s automatic vehicle location system for 51 bus and streetcar routes that are within a short walking distance of some subway stations. Using two statistical models, the paper results indicate that subway service interruptions have a statistically significant negative impact on bus and streetcar service operations in terms of slower speeds, with more immediate and intense impacts on streetcar service.