Abstract

High-quality public transportation improves the livability of neighborhoods, particularly in car-free or car-light urban environments. Public transportation is organized in a hierarchy, with different modes of transit serving different niches of travellers. Within this hierarchy, rapid rail provides the core service, operating vehicles with the highest capacity at the highest frequency. While ridership, fare provision, and other frequency-centric metrics have been at the forefront of public transit analysis, there is growing room for spatial metrics to describe connectivity within public transit. The Intermodality Index measures the average number of public transit connections at each rapid rail station within a given network. The full Intermodality Index is a composite of five intermodal paired indices that connect rapid rail to bikeshare, bus, ferry, rapid rail, and other rail services. By looking at intermodality through the lens of individual routes/services, this index approximates spatial intermodality since these routes/services serve unique geographies. Applying this index to the rapid rail networks of Canadian and American cities, we see that it favours networks that rely on intra-agency and supplemental rail and bus connections. Cities with minimal supplemental service providers and/or shallow intra-agency bus and rail service scored lower on this index. For bikeshare, overlapping service areas were highly conducive to higher intermodality. Ferry service was also notably dependent on physical geography to encourage intermodality.