Pedestrian and bicycle crossings may need to be protected from right turns as well as left turns in situations where there are high right turn volumes or speeds. The right turn volume threshold at which a protected crossing is appropriate can be still smaller for cycle track crossings. This paper explores a phasing scheme in which right turns as well as left turns have their own phase. The crossing runs at a different time from the turn phases, yet concurrent with the parallel vehicular through phase. This “protected-yet-concurrent” phasing scheme is far more efficient than using an all-ped phase. A general framework for sequencing phases accounting for the right turn – crossing conflict is shown using four rings instead of the usual two. Seven examples of protected-yet-concurrent phasing from the U.S. and the Netherlands are used to illustrate the scheme and to 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 phase re-service. Because protected-yet-concurrent phasing makes efficient use of time, it is also economical with space. While it requires right turn lanes, its use can reduce the needed number of through lanes, especially in comparison with all-ped phasing.
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