The Minnesota DOT (Mn/DOT) installed its first HAWK Pedestrian Signal on Highway 23 at 12th Avenue in St. Cloud, MN during October 2009. (jargon alert: HAWK = High-intensity Activated
crossWalK… creative). Here's more info on Mn/DOT's website. The City of Tuscon, Arizona pioneered this system and is now operating about 60 of them.
The HAWK System stays dark until a pedestrian activates it by pressing the push button. Then the signal starts flashing yellow, then steady yellow, then double red lights. The pedestrians get a walk signal with a countdown timer when the double red lights are activated. When the pedestrian gets the flashing hand symbol, the red lights start flashing for the vehicles. Once the pedestrian phase ends, the signal goes dark again and traffic goes back to free flowing.
Tom Dumont, Mn/DOT's District 3 Traffic Engineer, gave a presentation about the system to the City Engineers Association of Minnesota. The HAWK System is still in experimental mode and is not part of the Minnesota Manual on Uniform Traffic Control Devices yet. Mn/DOT developed criteria for when these systems could be installed based on roadway speed, crossing width, mainline traffic volumes, and pedestrian crossing volumes. This device fits a niche where full blown traffic signals aren't needed, but pedestrian safety at a high volume crossing is a concern. The system cost about half what a normal signal would (it cost about $80,000) and has limited effect on traffic since it is dark the vast majority of the time.
According to Tom's presentation, here are some of his observations –
- Vehicles did not stop for the dark signal (this was a major concern – vehicles historically have a tendency to stop at a dark signal, but the system is signed to encourage motorists to stop only on the red light).
- Its use was intuitive for pedestrians – there wasn't a learning curve.
- Some vehicles have a tendency to drive through on the beginning of the red light.
- The flashing red lights at the end of the phase caused some confusion. Mn/DOT is changing from both lights flashing red at the same time to a wig-wag flash (like the red lights at a railroad crossing).
I applaud Mn/DOT and St. Cloud for testing this innovative device!