The fondest dream of every Fresno motorist — green lights forever — has moved a bit closer to coming true.
The city's Public Works Department recently finished the synchronization of traffic signals along a stretch of Shaw Avenue in north Fresno.
Synchronization is a complex engineering task. For drivers, it's simple. In the case of Shaw, it means:
You're at Chestnut Avenue near Clovis.
Your destination is Golden State Boulevard, eight miles to the west.
You must pass through 24 intersections with stop lights.
In the old days, it was stop-go pretty much all the way.
Obey the speed limit now and you'll see a lot fewer red lights.
"The signals are now working as a system," Public Works Director Scott Mozier says. "This addresses a big frustration."
Traffic synchronization has been a lively political topic in Fresno for at least 25 years. Common sense says it's been a sore spot since the first street had three traffic signals in a row.
The incentives go beyond convenience. Fresno, with some of the worst air in the nation, doesn't need legions of cars unnecessarily idling at red lights. And Mayor Ashley Swearengin, keen on inner-city revitalization, wants a transportation system as frictionless as possible.
City officials say the Shaw Avenue project will cut the typical travel time from Chestnut to Fresno Street (near Fashion Fair shopping center) from eight to six minutes.
They expect travel time from Blackstone Avenue to Golden State to drop from 25 to 16 minutes.
All that fuel savings will mean more dollars in Fresnans' pockets and as much as a 34% reduction in vehicle emissions from Shaw traffic during peak travel hours, city officials say.
Shaw isn't the city's first busy street with synchronized lights. Herndon Avenue, Kings Canyon Road and Blackstone Avenue are among key corridors to already have gotten the treatment.
Mozier says the city wants to synchronize traffic signals along major corridors throughout the city.
If motorists want synchronization, and it makes such obvious sense, why has City Hall been slow to deliver?
Money is the obvious answer. Sometimes there is grant money to do a synchronization project, sometimes there's not. The Shaw project cost $7.6 million, $5 million from the feds, the rest from the state.
Another answer is technology.
Traffic engineers knew decades ago how to synchronize traffic lights on a busy street. They simply connected the lights to mechanical timers. Motorists soon recognized the pattern — if they traveled at a certain speed, they had a decent chance of avoiding red.
For example, it was conventional wisdom that a trip on Palm Avenue from H Street to Shaw at 33 mph was guaranteed to be green-light bliss.
But mechanical timers were the Model T of synchronization systems, incapable of easily adapting to fluctuating traffic volumes. A lot has changed since then.
Mozier says Fresno's synchronization system uses computers, fiber optics and wireless technology to customize traffic-signal strategy. Variables such as time of day are factored in. So, too, are shifts in development — for instance, a convenience store might open on what was once an empty field.
Mozier says the concept central to synchronization is a "platoon" of vehicles. The goal is for a platoon of perhaps 30 to 50 cars to make it through an intersection between red lights. As for car No. 51, well, that driver will be No. 1 in the next platoon.
Of course, no system can give all motorists nothing but green lights all the time.
Cross traffic must play second fiddle to cars on the busiest streets or synchronization doesn't make sense. Shaw is Fresno's second busiest street. The average daily traffic volume on Shaw at Cedar Avenue is about 49,400 vehicles. It's about 48,000 at Blackstone and at Fruit Avenue.
Herndon is busiest, with an average daily volume of about 75,000.
A lot can go wrong, too. Intersections are a mix of competing interests — motorists, buses, bicyclists and pedestrians intent on going straight, turning right or turning left. For example, detector loops, those devices embedded in the street that tell traffic-signal computers when someone is nearing an intersection, can wear out. City officials usually don't know of such failure until someone complains.
And it's not just traffic-signal computer systems that adapt. City officials know that motorists on synchronized Shaw will soon wonder why they get any red lights.
Synchronization "is a benefit to our quality of life," Mozier says. "We'll keep at it."
The reporter can be reached at (559) 441-6272 or firstname.lastname@example.org. Read his City Beat blog at fresnobee.com/city-beat.