The Parallel Flow Intersection: A New Two-Phase Signal Alternative

This paper introduces a unique signalized two-phase intersection design called the parallel flow intersection. This high-capacity design reduces signal phases, cycle length and conflict points. The layout of the parallel flow intersection expands a standard signalized intersection with the addition of turn bypass roadways parallel to the cross street. The bypass roadways remove left-turn conflicts from the main junction, allowing the signal to operate with two phases for each repeating cycle. The design offers the potential to reduce congestion at high-demand intersections with less impact and at lower cost than other intersection designs. It appears to be intuitive, flexible, safe and easily adapted to fit site requirements.