Transit Deserts: Equity analysis of public transit accessibility

Areas, where disadvantaged and transit-dependent populations are provided with inadequate amounts of transit supply, can be labeled transit deserts. Exploring transit deserts may help transit agencies improve accessibility to services while improving transit distribution and equity. This study utilizes the concepts of transit demand and transit supply to identify transit deserts in the City of Dallas. The comprehensive public transit accessibility (CPTA) score is introduced to evaluate accessibility to transit and to provide a holistic view of transit supply. While previous studies have primarily used proximity or spatial indicators to describe accessibility, this study utilizes a comprehensive set of spatial and temporal measures (connectivity to the network, connectivity to destinations, service frequency, flexibility, and time efficiency) to estimate accessibility to transit. Overlapping areas of high demand (transit dependency) and low supply (as measured using the CPTA) are then characterized as transit deserts. The CPTA score and its application to the analysis of transit deserts provides a universal framework which can be broadly applied by transit agencies, city officials, and transit stakeholders. The contributions of this study are as follows: first, developing a comprehensive framework to estimate transit supply or accessibility; and second, introducing a methodology for identifying transit deserts.