How to Regulate Traffic in a Sustainable World

Busy intersections have been regulated by traffic lights for more than a century. The blueprint for modern traffic signals, the three-color signal head, appeared in 1920. The first dedicated pedestrian signals appeared a decade later, and a prototype that defined a clear, exclusive pedestrian phase was tried out in New-York in 1934. Fast forwarding to the 21st century, walking has come back in force as the backbone of active transportation, as society strives to promote more sustainable transportation. Transit is getting the lion's share of attention and research in the traffic field, while cycling is integrated into public infrastructures through upgrades or complete streets rebuilds. Modern traffic controllers offer tremendous computing power, giving traffic engineers increased flexibility when orchestrating movements at an intersection. Measures that both protect the pedestrian and allow vehicular traffic to progress elevate the status of walking while not impeding the flow of transit and other vehicles are hidden in that computing power, and have been there for years. This paper relates the historical steps in the pedestrian signalling world. It is intended as a toolbox of pedestrian-friendly measures for practitioners, some actively putting walking front and forward at no cost. Measures like the Leading Pedestrian and the Walk phase extension are simple functions available in modern traffic controllers. Other measures like the pedestrian countdown timer and the Through Arrow Leading Walk Interval are simple to retrofit during traffic signal upgrades and are of much benefit to pedestrians. For the covering abstract of this conference see record control number 201111RT334E.