Transit Access Measure: Incorporating Walk and Drive Access

Document Type

Journal Article

Publication Date


Subject Area

place - north america, planning - methods


Transit access, access to opportunities


The purpose of the transit system is to connect groups of people to work, school, fresh food, recreation, childcare, and other opportunities. Quantifying transit access to opportunities provides a powerful way to understand the utility of the transit system in meeting the needs of the regional population. The most widespread use of access to opportunities measurement is one that quantifies the number of jobs accessible from residential zones within a given time threshold. Wishing to better understand access to opportunities in the six-county service area of the Regional Transportation Authority (RTA) in Chicago, Illinois, RTA developed a method to measure access at given time thresholds that, compared with existing methods, refines the geographies that have walk access to transit and incorporates multimodal access to transit by automobile. RTA also developed a transit access score, which highlights the relative access to opportunities from an origin on a scale of 0 to 100. This score weighs the value of opportunities by the time it takes to access them. The transit access score can be used in public engagement, project evaluation, performance measurement, and other applications to provide a meaningful measurement of access without specifying exactly what quantity of opportunities is enough or which travel time threshold is most appropriate.


Permission to publish the abstract has been given by Transportation Research Board, Washington, copyright remains with them.