Chandra Kiran B. Krishnamurthy (CERE, SLU) and Nicole S. Ngo (University of Oregon) have recently published their article Do micromobility systems promote public transit usage? Evidence from U.S. Cities in Transportation Research Part D: Transport and Environment. See article here.
Micromobility is a relatively new mode of travel in urban areas. This term includes quite a few modes, including bicycles (docked and dockless) and e-scooters. As these have rapidly increased in number and density in cities across the U.S., an important question arises with significant public policy implications: how do micromobility systems affect public transit usage? Does it substitute for transit (largely bus) trips, thereby reducing the viability of these services? Or does it complement transit, by e.g. providing the “last-mile-connectivity” that is often lacking in many smaller cities or outlying areas of a city, thereby bringing new users?
It is precisely this question that the paper seeks to address, by using data on different micro-mobility services for 300 metropolitan areas the U.S. over a five year period (2015-2019). Over this period, 131 cities had at least one micro-mobility program active over some time of the study period. This study uses UPT (unlinked passenger trips) per capita and the number of active micro-mobility programs as measures of transit usage and micromobility program prevalence resp. in a given city. Using these metrics, this study finds that an additional micromobility program in a city yields an increase in UPT per capita of 1.2% of (pre-program-increase) mean UPT. This is a sizeable increase, with e-scooters largely responsible for this effect, with the effect pronounced in smaller cities with lower transit usage on average. These findings, while not causal, suggest that micromobility systems generally, and e-scooters specifically, complement public transit. They also suggest potentially a social value in supporting micromobility systems if increased transit usage is a goal, as it is in many cities across the U.S.