Crosswalk Confusion: Massachusetts Drivers Flummoxed by Pedestrian Hybrid Beacons, UMass Amherst Researchers Find

Stopping early, failing to stop or rolling through-new research from University of Massachusetts Amherst reveals that more awareness of the rules of the road around this crosswalk design is necessary. Published in Transportation Research Record, the study looked at how Massachusetts drivers behave at pedestrian hybrid beacons, a type of crosswalk device increasingly found at mid-block crosswalks where there is not a full traffic signal.

Across the state, 40 pedestrian hybrid beacons (PHBs) are installed and, with more in planning stages, the confusion is a real safety issue, researchers say. PHBs have five phases of indications that communicate to motorists what to do, which allows for a greater flow of traffic than a traditional stop light while maintaining higher pedestrian visibility than similar beacon designs.

The PHB remains "dark" when no pedestrian has activated it, and drivers proceed as usual. When a pedestrian pushes the walk button, the yellow indication begins to flash, indicating that cars should slow down. The yellow indication turns solid, telling drivers, "prepare to stop." When the PHB transitions to solid red, drivers are required to stop and yield to pedestrian traffic, which sees a traditional "walk" indication. Finally, flashing red means stop and proceed if the crosswalk is clear, as a driver would do at any stop sign.

The researchers found that across 10 sites within Massachusetts, on average, nearly a quarter of drivers drove through during the solid red phase, and 65% of drivers drove through the flashing red regardless of pedestrian presence, which is the equivalent of running a red light and running a stop sign, respectively.

This is a safety issue. "A lot of the 65% [of drivers who go] during the flashing red are drivers that are waiting in the line of cars, but then they roll through," says Angelina Caggiano, lead study author and a Ph.D. candidate in transportation engineering at UMass Amherst.

"That's especially problematic for rail trail or shared-use path locations, because there are going to be cyclists, runners or people traveling at faster speeds trying to catch that flashing red interval to cross the street before the walk signal ends. Whereas cars are now rolling through, and they may not see those secondary pedestrians."

At the same time, there were instances of stopping too soon, causing further confusion for drivers: overall, 9% of drivers stopped when the lights were dark and 19% of drivers stopped during the flashing yellow phase, both phases where drivers are expected to proceed, or proceed slowly. (Another 30% of drivers stopped during the solid yellow. "That makes sense because even if we're approaching a traffic signal, there are going to be some people that stop when that traffic signal turns yellow, anticipating that it's going to turn red," Caggiano adds.)

"They're stopping because they see a pedestrian and they're going to allow them to cross, regardless of what the PHB is communicating," says Caggiano. This early stopping, as Caggiano calls it, doesn't cause an immediate issue for the pedestrian-they see a car stop, and they choose to cross. However, it does cause driver confusion when the following cars then see a red light but no pedestrians at the crosswalk. This may contribute to unsafe instances of cars driving through the solid or flashing red lights if drivers incorrectly assume that no pedestrians are present.

The researchers also found that the type of roadway impacted how drivers interacted with the beacon. On four-lane roads, there was less premature stopping, but also lower rates of stopping during the red-light phases: 29% drove through the solid red and 69% drove through flashing red.

At rail trail crossings, correctly stopping at red phases was comparable to average (26% and 64% failed to stop), but more cars were stopping during the dark, flashing yellow and solid yellow intervals (19%, 32% and 41%, respectively). "The pedestrian presence is so expected by drivers that they're more likely to yield sooner," explains Caggiano. Again, this causes further confusion for drivers arriving later in the sequence and may contribute to unsafe conditions for pedestrians or cyclists crossing towards the end of the walk interval.

"That's really leading Angelina and myself to make a recommendation that careful consideration should be given to whether or not it's actually the best device to use at rail trail crossings or locations where there's a steady stream of pedestrians and cyclists," says Michael Knodler, the William W. Boyer Endowed Professor of Engineering in the Riccio College of Engineering at UMass Amherst, director of the UMass Transportation Center, and one of the authors of the paper.

Driver performance for correctly stopping during the solid red phase was best at urban, two-lane roads: only 11% of drivers failed to stop. There was still some stopping confusion in the other phases, but generally more compliant than other sites.

Caggiano says that most of these successful beacons are in the Somerville and Cambridge area, where both drivers and pedestrians seem generally more familiar with the PHB system. "We also observed higher levels of pedestrian compliance in these environments, so pedestrians were far more likely to push the button and wait for that walk indication, as opposed to drivers stopping for them early, and then crossing the road," she adds. Pedestrian behavior will be the subject of a future paper.

"Pedestrian safety continues to be a national priority, given the number of fatalities and these devices seem to have a lot of promise," says Knodler. "As these devices become more common, we expect to see behavior continue to improve at these locations. And so, given what we know are the benefits that they provide, I think that's one reason for optimism."