New Traffic Safety Enhancement Gives Pedestrians a Head Start at Ada County Intersections
A subtle traffic safety improvement could be buying you some time — and protecting you from distracted drivers — at street corners across Ada County.
You’ll soon be getting a head start crossing intersections with walk-light timing adjustments planned by the Ada County Highway District. Traffic engineers are reprogramming walk lights at every corner to turn on before traffic signals turn green, making you easier to be seen by drivers making a right or left turn through the crossing.
The enhancements, called leading pedestrian intervals, or LPIs, are new to the county, though they have become common across the country in the last decade. They’re being installed in the midst of a spike in cars colliding with people, including at one Boise intersection where drivers hit four people, killing one, this year. Research has shown that the strategy can reduce the odds of those accidents happening to you.
We tracked down answers to six questions about the changes:
1. How does the timing of the walk lights work?
Engineers program the traffic lights at an intersection to turn green three to seven seconds after the walk sign turns on for people crossing the street, said Paige Bankhead, an ACHD engineer leading the project to install the intervals. Walk lights turn on at the same time as traffic signals in intersections without the new sequence.
2. Why is the head start important?
The timing makes pedestrians easier to see for turning drivers, according to Bankhead.
3. How long is the head start?
The length of the head start depends upon the length of the crossing. Ryan Head, ACHD’s deputy director of development and technical services, stated that the duration of the interval should be long enough to allow pedestrians to cross at least one lane before the light turns green.
4. What is driving the need for these safety measures?
The highway district has seen a spike in the number of people being killed by cars this year. Head reported that there were six pedestrian fatalities last year, but already 16 pedestrians have died this year.
5. Will this fix all crashes involving pedestrians?
Head makes it clear that the leading pedestrian intervals are not a cure-all for every crash, but research indicates that it is expected to reduce the number of accidents.
6. How effective are these intervals?
Lily Eleftariadou, director of the University of Florida Transportation Institute, explains that pedestrian intervals have been shown to reduce the number of collisions between cars and people by as much as 60%. She emphasizes that it reduces the possibility of conflict and makes pedestrians more visible to drivers.
ACHD plans to program the intervals into all 457 signalized intersections in the highway district. However, implementing this change will require several years to complete. The agency aims to prioritize intersections based on factors such as existing accessible push button setups and their impact on coordinated signal networks. Additionally, the district will need more data before estimating the cost of the project, as it may require additional changes and equipment upgrades.
In conclusion, the implementation of leading pedestrian intervals in Ada County is an important step towards improving the safety of pedestrians crossing intersections. By giving pedestrians a head start and making them more visible to turning drivers, it aims to reduce the number of accidents and fatalities caused by collisions between cars and pedestrians. While it may not solve all the problems, research shows that these intervals can significantly reduce the likelihood of such incidents. With the planned installation of these intervals at all signalized intersections in the county, Ada County is taking proactive measures to protect its pedestrians and create a safer environment for everyone on the roads.
