By Michael Brenneis
Accessibility analysis, measuring the ease with which people can reach destinations, could shift the paradigm in the fields of land use and transportation planning. Where traffic speeds once reigned supreme, momentum is building behind the adoption of a more comprehensive metric. While uptake has thus far been somewhat diffuse among cities, metropolitan planning organizations (MPOs), and states, those who have the capacity and resources to implement accessibility analysis find it a powerful tool for leveling the playing field between modes, focusing on the movement of people over vehicles, and centering the needs of under-resourced communities.
A recent study surveyed practitioners who use accessibility analysis in their work. Preliminary findings indicate accessibility analysis is extremely useful when addressing non-auto modes, corridor studies, and equity and discrimination issues, and very useful for project evaluation and plan assessment. They also find it straightforward to run and interpret.
Those agencies that use accessibility analysis tend to be reform minded—open to the utility of metrics that are not directly congestion-related. While there is currently no federal mandate to measure accessibility as a performance metric of the transportation system, provision has been made in the IIJA for an accessibility pilot project (p.48).
At the state level, agencies have developed programs that allow projects that include infrastructure for active modes of travel to be competitive for funding in ways they might not be otherwise—Virginia’s Smart Scale, for example. At the city and MPO levels, SSTI’s latest webinar featured a number of examples currently in use. The Wasatch Front Regional Council ran through the workings of a tool they developed to measure a given project’s effect on access to jobs by different modes and for communities of interest. The Sacramento Area Council of Governments demonstrated analysis that will help them plan projects where they will have a positive impact on residents’ multimodal access to destinations. And the Los Angeles Department of Transportation demonstrated some of the accessibility tools that allowed them to secure funding for safety and connectivity improvements to benefit multimodal travelers.
Accessibility analysis does have its challenges, however. As several of the webinar presenters pointed out, the concepts of accessibility analysis can be difficult to explain to those outside the field. The authors of the research cited above suggest that agency staff who are less familiar with accessibility analysis are more challenged by it than those who are standard or advanced users. Lack of exposure or familiarity among agency leadership could prove to be an impediment to wider use, but as accessibility analysis becomes more visible, more planners and engineers will likely take a brighter view.
According to this paper, some practitioners avoid using accessibility analysis in rural areas because they believe that residents prefer to be isolated, and are content driving everywhere they need to go. However, many households in rural areas spend a considerable proportion of their income on transportation, are isolated because they can’t drive or can’t afford a car, or rely on ride sharing or poor quality transit—all issues that accessibility analysis could help address.
For those seeking practical applications or advice on getting started, the SSTI webinar Measuring Accessibility: Planning for Success and the Measuring Accessibility guidebook would be good places to start.