Bicycle level of stress and equity as factors in project selection

By Robbie Webber

A paper published in the International Journal of Sustainable Transportation suggests integrating accessibility by bicycle, equity, and project selection to tackle the isolation and segregation of low-income neighborhoods in Baltimore. Using bicycle Level of Traffic Stress (LTS) to measure both access to common non-work destinations and disparities in access across different neighborhoods, the authors suggest that projects can be prioritized to improve outcomes for residents that do not own cars and struggle to reach destinations to meet their daily needs.

Although Baltimore has a Bicycle Master Plan, the existing network is fragmented and does not serve transportation purposes in many areas of the city. In addition, bicycle facilities may not offer a comfortable riding option for less-skilled or inexperienced bicyclists. Previous research has shown that a low-stress network is key to increasing bicycle mode share. The researchers used the Level of Traffic Stress methodology developed by the Mineta Transportation Institute to map the current low-stress network. Facilities that cross arterials without a signal are downgraded for the link next to the crossing because the intersection creates a gap in the low-stress network.

Once the low-stress network was mapped, the researchers added important destinations and calculated the accessibility within two miles using only the low-stress network. A small number of key destination types were used because of the importance they held for low-income and underserved communities. The destinations selected were grocery stores, pharmacies, banks, and public libraries. The researchers also calculated the difference in accessibility between residents who were black, living in poverty, or in zero-car households versus the population as a whole. (Although the initial analysis looked at a variety of racial and ethnic minorities, prioritization was given to analysis of access for black residents because of the history of extreme segregation and outcome disparities in Baltimore.)

Proposed bicycle projects were then ranked based both on how they would improve access and address equity across the city. Some projects would improve access to nearby destination, while others would provide connections to the existing low-stress network and expand the service area—the area that could be reached using only the low-stress facilities. To assess the equity impact, the researchers calculated the percentage of affected residents who were either black, in poverty, or in zero-car households.

The current Bicycle Master Plan approaches project prioritization by starting in the downtown and creating a robust network extending outward. The researchers suggest instead considering the impact on disadvantaged communities. These communities have historically been overlooked when bicycle projects are planned, are less involved in public outreach efforts, have been disproportionately affected by past transportation projects. Access to key destinations is especially important for households that do not have access to a car. Despite the expectation that only a small portion of the population will choose to travel by bicycle, the ability to use this option will have a big impact.

Although there are many considerations when planning future bicycle projects, this paper offers one method to address racial and income disparities in Baltimore while also offering improved access to key destinations by connecting the low-stress bicycle network.

Robbie Webber is a Senior Associate at SSTI.