Spatiotemporal accessibility to supermarkets using public transit: an interaction potential approach in Cincinnati, Ohio

• Transit commuters in some food deserts have increased access to supermarkets.
• Automobile drivers experience more access to supermarkets in the urban periphery.
• Some low-income regions with low transit access are not deemed food deserts.

Improving nutrition in urban regions involves understanding which neighborhoods and populations lack access to stores that sell healthy foods, such as fruits and vegetables. To this end, recent work has focused on mapping regions without access to places like supermarkets, often terming them ‘food deserts’. Until recently, this work has not considered residents’ mobility as facilitated by transportation systems, and even among those that do, few have considered alternative forms of transportation, like public transit, opting for automobile-oriented travel assumptions. This paper analyzes people’s spatio-temporal constraints to accessing supermarkets, and focuses on the transit commuting population. Analysis of commute data from Cincinnati, Ohio shows there are a significant number of residents that have improved access to supermarkets when a grocery shopping trip is made on the way home from work, than if they were to depart from their home location. These results extend previous work showing relatively few automobile commuting residents have better access to supermarkets given their work locations.