Backups at busy Northampton intersection result from glitches in new traffic signal system for buses
NORTHAMPTON — Recent bottlenecks at one busy downtown intersection near the Academy of Music are the result of programming glitches in a new traffic signal system that allows transit buses to extend the length of time lights stay green on Route 9.
The technical problems have led to repeated backups at the intersection where Main, New South, West, Elm and State streets converge. The state Department of Transportation is aware that the traffic lights are no longer synchronized at that intersection and is working to fix the issue, said Edward S. Huntley, director of the city’s Department of Public Works.
“They reprogrammed the new controllers but didn’t get it quite right,” Huntley said.
The new so-called transit signal priority system is designed to enable Pioneer Valley Transportation Authority bus drivers to extend a traffic signal’s green light when approaching an intersection. The extra time allows the intersection to clear and the bus to proceed without being delayed.
Unlike systems used by emergency response vehicles that stop traffic outright to get through an intersection, the system bus drivers use is intended to keep the light green for a few extra seconds and only when a bus approaches within 400 feet of an intersection.
The system has been installed as part of a $232,800 DOT project at 10 signalized intersections on Route 9 from the veterans hospital in Leeds to the intersection at Hawley and Market streets.
When working properly, Huntley said, all the lights at the intersection should work in unison as they typically do, except for a slight delay of a few seconds when a bus triggers a light to stay green.
“Most people won’t notice the difference,” Huntley said.
The problem in this case, he said, is that not all the lights at the intersection are working in unison. For example, cars waiting on New South Street to turn left onto Elm Street get a green light to enter the intersection but then must stop at a red light at the Elm-West intersection. When working correctly, the second set of lights is designed to stay green long enough for the intersection to clear.
Huntley believes this is the only intersection experiencing major problems, though he did field a concern about backups reported at the Hawley-Market intersection.
The transit signal priority systems have been used successfully in other communities, including Springfield, for some time. The PVTA has said the system helps increase on-time performance for its fleet, decrease travel times for express bus routes during rush hour, attract and retain riders and reduce congestion-related emissions by decreasing bus idling times.