November 19, 2004
Scottsdale is trying to ease congestion on Shea Boulevard by switching the way left-turn signals work, and in some cases that means drivers won’t see the lagging left signal used so often across the city.
Drivers will see the new signal operation after morning rush hour Monday at six intersections, said Steve Ramsey, the city’s senior traffic engineer.
"They should be able to go much farther without having to stop at a red light," Ramsey said. "It’s never going to be perfect but they should be able to stop less often."
This should reduce travel times on Shea by 10 percent to 15 percent, Ramsey said.
The intersections will switch to a combination of lagging and leading arrows. For instance, drivers going eastbound may get a green arrow at the same time other eastbound drivers have a green signal to continue straight. The westbound drivers would get a green arrow at the end of that cycle.
The signals will switch a couple times a day in some cases, so drivers at a specific intersection will have to get used to seeing lagging left signals at some times but not at others, Ramsey said.
Drivers may see adjustments in the next few weeks as traffic engineers make sure the changes correspond to the flow of traffic.
"Once it’s all set up and we’ve got it fine-tuned, it will be predictable," Ramsey said. "It’s not random."
This type of signal operation is common in places where high-volume intersections are placed close together, such as shopping malls.
The changes will take place where Shea intersects 64th Street, 70th Street, Scottsdale Road, Hayden Road, Loop 101 and 90th Street.
Drivers on Hayden will see similar changes at the Shea intersection.