Mitigating Right-Turn Conflict with Protected Yet Concurrent Phasing for Cycle Track and Pedestrian Crossings

Abstract

Where there are high turn volumes or speeds, pedestrian and bicycle crossings may need to be protected from right turns as well as left turns. Cycle tracks may need protected crossings even where right-turn volumes are modest. This research explores a phasing scheme in which right turns have their own phase and bike and pedestrian crossings run in their own distinct phase concurrent with the parallel vehicular through phase. This protected yet concurrent phasing scheme is more efficient than an all-pedestrian phase. A general framework for sequencing phases accounting for the right turn and crossing conflict is shown with four rings instead of the usual two. Seven examples of protected yet concurrent phasing from the United States and the Netherlands illustrate the scheme and characterize its likely impacts in terms of delay and street footprint. Overall delay and footprint impacts are found to be modest; factors that affect the impact of protected phasing include complexity of the phasing plan, coordination, and the possibility of using reservice. Because protected yet concurrent phasing makes efficient use of time, this phasing is also economical with space. Although the phasing requires right-turn lanes, its use can reduce the necessary number of through lanes, especially in comparison with all-pedestrian phasing.