Murrysville drivers will enjoy green all the way on Route 22 as traffic engineers adjust signals
Imagine getting every green light while driving on Route 22 in Murrysville.
It's not as far-fetched as it sounds.
Traffic engineers spent weeks scrutinizing scientific formulas to perfect how signals need to change to keep traffic moving and commuters happy. Among their recommendations: a GPS time-clock system and shortening the signal cycles during peak hours.
“By the end of summer, we hope to have the (traffic signal) timings implemented,” said Mark Szewcow, a traffic engineer with Pittsburgh-based Trans Associates. “It is recommended that you go out and retime traffic signals and corridors every five years. I think you can tell from driving around the area, that doesn't happen a lot.”
The nearly 10-mile stretch of Route 22 in Murrysville at times causes headaches for the 22,000 drivers a day who travel it and complain it's stop-and-go at every intersection.
“The red lights are horrible,” said Sally Joller, 66, of Export. “You sit and sit.”
Joller relies on Route 22 to get from her Export home to work in Murrysville during the week. She also uses the thoroughfare to get to Monroeville to shop on weekends.
The Harrison City Road and Route 22 intersection is the “worst,” she said, because of its lengthy signal cycle.
“The cross traffic goes twice before it's your turn,” Joller said.
Providing that cars cruise along at the 45 mph speed limit, the changes this summer could ease their pain.
The recommendations stem from a $37,000 traffic study sanctioned by the municipality's council. In the first phase, engineers inspected wiring and operation of pedestrian buttons at signals. In the second, data were collected at three major pinch points: between Trafford Road and Gates Avenue, School Road near the Sheetz convenience store and between Harrison City-Export Road and Manor Road.
The data pinpointed four peak periods for traffic on Route 22: 7 to 9 a.m., 1 to 3 and 4 to 6 p.m. weekdays; and 2 to 4 p.m. Saturdays.
Traffic signal timings are set to deal with only three peak times, excluding the evening period. By adding that fourth timing for signals, Szewcow said, traffic will be streamlined, decreasing backups.
“You have five locations currently that have storage areas — either left turn lanes or space between intersections — that during peak times, those cars bleed out,” he said. “Under proposed conditions, we got that down to one.”
Another proposed change is to shorten the cycle of time it takes for a signal on Route 22 to move from green, then move cross-direction signals, back to the green for Route 22. Currently, each signal is set to 120 seconds.
“That's the industry standard for these types of signals,” Szewcow said. “We're shortening it a little in the morning and afternoon. That's primarily because what we're seeing out there are a lot of intersections that have less traffic on the side streets. We're thinking shorter cycle lengths make the system work faster.”
Morning and afternoon cycles would be cut to 105 seconds and 110 seconds, respectively.
Some cycles could be cut to 60 seconds during evening peak hours, officials said.
Finally, syncing signals to communicate with each other will enable drivers traveling at the speed limit to hit every green light, as opposed to the current stop-and-go conditions.
“Assuming that you hit green at the start from Trafford Road and you're traveling the speed limit, you won't hit red again,” Szewcow said. “Now that's a bandwidth. That's not every car, but you should get all greens.”
To achieve that, engineers suggest the municipality switch to a GPS time-clock system from its radio-based system. The system would alert each traffic signal to the time of day and move the signal to the correct cycle length for that peak period. For example, signals would switch to a 105-second cycle from a 120-second cycle when the day's first peak hour begins at 7 a.m.
“If the goal of council is to move traffic through the mainline, these proposed timing changes will accomplish that,” said Jim Morrison, chief administrator.
Trans Associates will work with the state Department of Transportation to finalize a traffic plan. New timings would be implemented by a timing contractor this summer.
It takes about half a day for contractors to implement the timings remotely from a control cabinet.
Amanda Dolasinski is a staff writer for Trib Total Media. She can be reached at 724-836-6220 or firstname.lastname@example.org.