A comparative analysis of pedestrian network connectivity and accessibility using network approximation: Fid-Bau Portal

A comparative analysis of pedestrian network connectivity and accessibility using network approximation

Hennessy, Emily Rose / Ai, Chengbo

Highlights • Introduction of a new method for approximating pedestrian networks in GIS. • Novel pedestrian application of alpha, beta, and gamma connectivity indices. • Four cities analyzed to compare optimal and accessible pedestrian networks. • Accessible pedestrian networks exhibited an average reduction of 48.48% connectivity.

Abstract Since the introduction of the Americans with Disabilities Act (ADA), transportation stakeholders have endeavored to include compliant and accessible pedestrian facilities as a part of their roadway improvement and maintenance projects. These projects, often completed in sections, have resulted in piecemeal pedestrian networks with limited holistic ADA compliance in many areas, the full extents of which are often unknown. This research introduces a methodology for approximating pedestrian networks and then employs the resulting data in a comparison of the connectivity of optimal and accessible pedestrian networks. The pedestrian network approximation method used street centerline and curb ramp data in combination with GIS tools to generate pedestrian optimal networks across four metropolitan areas: Cambridge and Boston in Massachusetts, and Seattle and Tacoma in Washington. These optimal network extents were then analyzed for ADA compliance to create accessible network models where only ADA compliant routes remained. Traffic Analysis Zones served as analytical units, for which alpha ( $α$ ), beta ( $β$ ), and gamma ( $γ$ ) structural connectivity indices were calculated to compare the two pedestrian network conditions for each city. On average, the four cities exhibited a 93.47% reduction in alpha connectivity, and a 48.48% reduction in both beta and gamma connectivity indices, confirming that pedestrians depending upon ADA compliance for travel experience severely reduced mobility.