Making Quick-Build Sidewalk Extensions Accessible to Pedestrians with Vision Disabilities

Quick-build sidewalk extensions that shorten crossing distances and improve visibility between drivers and pedestrians waiting to cross the street are understood by most travelers, but wayfinding is difficult for pedestrians with vision disabilities who are unlikely to know they exist without specific familiarization. This research evaluated the effectiveness of three potential treatments for mitigating these wayfinding problems, all of which resulted in improvements in measures of wayfinding: 1) removing the detectable warning surface (DWS) from the curb ramp and installing DWS across the width of the crosswalk at the perimeter of the sidewalk extension; 2) placing a 24-inch wide strip of raised-bar tactile direction indicators with bars oriented perpendicular to the crossing direction along one side of the curb ramp and extending through the sidewalk extension to the DWS at the perimeter; and 3) placing trapezoidal tactile warning delineators (TWDs) along the edges of the crosswalk, within the sidewalk extension, to delineate the pedestrian path. A combination of moving the DWS and installing TWDs along crosswalk edges resulted in the most accurate and effective wayfinding to and through the quick-build sidewalk extension. The spacing of vertical perimeter elements (e.g., flexible posts) to ensure they were detectable by pedestrians with vision disabilities was also evaluated. Participants who traveled outside the crosswalk reliably encountered and detected at least one vertical perimeter element when the maximum separation between vertical elements was 24 inches. The perimeter was not reliably encountered and detected when the separation between vertical elements was considerably greater.