Ranking Transit Accessibility

Andrew Owens and David Levinson at the University of Minnesota’s Center for Transportation Studies have released Access Across America: Transit 2014. The study examines the accessibility to jobs by transit in 46 large metropolitan areas in the United States. It claims to be “the most detailed evaluation to date of access to jobs by transit,” and is unique in that it “allows for a direct comparison of the transit accessibility performance of America’s largest metropolitan areas.”  Atlanta did not fare well, ranking 30th out of the 46 cities. The AJC has a short piece on the study and WIRED magazine has a longer one.

The study’s focus on accessibility is part of an emerging shift in transportation planning away from congestion and throughput as the key metrics for evaluating our transportation system. We travel because we need to get somewhere – work, school, the store, etc… – and accessibility measures how easy it is to get there. Congestion, in contrast, measures the condition of the road used to travel to a destination.  But focusing on congestion ignores other factors that make it difficult to reach a destination, like the distance that must be traveled. And congestion is largely meaningless for non-automobile trips like walking or taking the train.  Accessibility offers a superior metric because it is mode neutral and because it measures what we actually care about – how easy it is to get where we are going.

Accessibility is a function of both transportation and land-use decisions, which has important policy implications. There are two broad avenues to increasing accessibility: improving transportation systems and altering land-use patterns. Neither of these things can be easily shifted overnight, but over time they do change—both through direct plans and action and through market forces.

Cities that scored well in the study combined relatively dense land use with fast, frequent transit service. As the report’s online mapping tool illustrates, metro Atlanta’s transit accessibility is relative strong in the urban core but declines quickly as one moves away from the MARTA rail system.

It is not surprising that metro Atlanta, with its sprawling land use and limited transit service, struggles with accessibility generally and transit access to jobs specifically.  Comparing Atlanta to high-scoring San Francisco and Washington, D.C., the study notes that all three have heavy rail systems but Atlanta scored significantly worse due to its decentralized job distribution. As metro Atlanta’s transit service expands for the first time in years and its real estate development increasingly focuses on infill development, particularly TOD, improvements in transit accessibility are likely to follow.

The authors plan to update the Access Across America study annually, allowing Atlanta’s accessibility to be viewed both as a snapshot in time and a long term trend. It will be interesting to see how the Atlanta Streetcar, MARTA’s TOD initiatives,  and the (potential) expansion of MARTA into Clayton County improve accessibility in the region.