I’ve found, in my walks and rides through cities, that traffic signals really impact my route selection. I avoid intersections where I need to wait a long time or need to cross in multiple stages (the completely awful waiting on a traffic island with traffic speeding by on both sides). In other words, from my perspective at least, traffic signals have a huge impact on pedestrians and cyclists.
On the other hand, some cities are changing their traffic signals to improve walking and cycling. Methods include count-down timers, improved timing to reduce pedestrian wait times, using sensors to detect waiting pedestrians rather than forcing them to push a (beg) button and green-wave timing for cycles.
I thought it would be interesting to comprehensively document these techniques for using traffic signals to encourage (or at least, not discourage) walking and cycling. Therefore, in 2020 I prepared a research proposal for developing a set of best practices for using traffic signals to encourage walking and cycling. Here’s the abstract:
Traffic signals are a key element of urban transport. They allocate, in time, street space to users. Traffic signals were invented as part of the effort to make room for motor vehicles in the early 1900s. Traffic signal planning, arguably, incorporates an unconscious bias towards prioritising motor vehicle flow. Furthermore, traffic signal planning (e.g., timing, phasing, location) is complex, making it difficult for non-specialists to effectively participate in design decisions. Some cities are using traffic signals to increase walking (e.g., smart signals) and cycling (e.g., green waves), but many of these strategies and their detailed engineering are not widely known. The project’s objective is to identify, design and communicate strategies for using traffic signals to increase the use and safety of walking and cycling. Therefore, this project will bring together traffic signal planners with academics, NGOs and local residents, to survey existing methods, develop new strategies, and broadly communicate recommended best practices, for using traffic signals to encourage walking and cycling. Importantly, because autonomous vehicles will also need some process for allocating right-of-way at intersections, the project will consider how the best practice strategies can be implemented in both today’s traffic signals and tomorrow’s autonomous vehicle control software.
One of the proposal’s organising concepts was that we currently focus on allocating street space … we should think more systematically about allocating TIME. For example: Why, when most cities have the goal of encouraging walking and cycling, do they focus on timing their signals to encourage driving?
We also planned to develop and investigate new technologies and practices that could be applied to traffic signals to help encourage walking and cycling like using sensors to give early green phases when pedestrians or cyclists are waiting – but there is no opposing vehicle traffic.
Unfortunately the proposal was rejected by the funding agency, but I still think it would be an excellent research project. Contact me and I can send you more information and put you in contact with my excellent team of collaborators.
- Levinson, David (2018). Signalling inequity – How traffic signals distribute time to favour the car and delay the pedestrian. Transportist.
- More David Levinson’s posts on traffic signals in Transportist.