A GIS Based Assessment of Urban Public Transport Accessibility in Columbus, Ohio

• Main Author: Alam, J. A. M. Mostahidul
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2023
• Subjects: Geographic information science; Geography; Transportation
• ISBN: 9798381400465

In recent years, research on accessibility to urban services through public transport has gained popularity due to its direct impact on urban socio-economic disparity. While evaluating accessibility to urban services is crucial, there remains a significant gap in assessing the level of access to public transport in urban areas. The widely used PTAL methodology for assessing public transport access has limitations that can undermine the accessibility of certain areas. To address this, the present study revised the methodology to incorporate and evaluate access from both non-residential and residential units in Columbus. Additionally, the study examined the accessibility to urban services via public transport to understand socio-economic disparities among different groups and neighborhoods. The findings reveal that the revised PTAL methodology better suits Columbus, and it is observed that the level of access to public transport does not decline gradually outwards from the downtown, rather the study area have pockets of high access at different Block Groups. Moreover, even though the access index values represent the level of access in the study area, the Equivalent Doorstep Frequency derived from the access index shows stronger correlation with accessibility indicators, meaning it has stronger influence on accessibility to urban services. The disparity in public transport-based accessibility to urban services aligns with the patterns observed in other US cities, where poor and minority groups in the inner city tend to have substantially better accessibility to urban services. The disparity in transit-based accessibility among different socio-economic groups in different neighborhoods indicates that many poor BGs will not be benefitted by the future transit service improvement projects. Notably, the BGs with high concentration of poor in Northland, Northeast and East Columbus neighborhoods have very poor accessibility to urban services by public transport yet the proposed plans by COTA will mostly cater to the BGs in neighborhoods with relatively better accessibility.