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Los Angeles synchronizes all traffic lights

Posting in Cities

There are many frustrating aspects of driving. Getting a green light just to be funneled to a red light a block or two down the street has to be near the top of the list. Fortunately, for drivers in one of the most congested cities in the United States, that's no longer a problem.

Los Angeles recently launched an automated traffic control system that synchronizes all of its nearly 4,400 traffic lights over 469 square miles. City officials say it's the first major city in the world to synchronize its traffic lights.

How does it work? The New York Times reports:

The system uses magnetic sensors in the road that measure the flow of traffic, hundreds of cameras and a centralized computer system that makes constant adjustments to keep cars moving as smoothly as possible. ...

[T]he magnetic sensors in the road at every intersection send real-time updates about the traffic flow through fiber-optic cables to a bunker beneath downtown Los Angeles, where Edward Yu runs the network. The computer system, which runs software the city itself developed, analyzes the data and automatically makes second-by-second adjustments, adapting to changing conditions and using a trove of past data to predict where traffic could snarl, all without human involvement.

The city estimates that the system will increase travel speeds by 16 percent and reduce travel time by 12 percent. And because of reduced idling time, the city says it will save 1 million metric tons of carbon from entering the atmosphere.

But it's not just cars that benefit from the new system, the Times reports, buses running behind schedule could see extended green lights and the sensors can also detect bicyclists. The system can't detect pedestrians but it does extend walk signs during major events. In other words, doing what a transportation network should do: get people where they need to go quickly and efficiently.

To Fight Gridlock, a City Synchronizes Every Red Light [New York Times]

Photo: Flickr/Bill Selak

— By on April 2, 2013, 2:11 AM PST

Tyler Falk

Contributing Editor

Tyler Falk freelance journalist based in Washington, D.C. Previously, he was with Smart Growth America and Grist. He holds a degree from Goshen College. Follow him on Twitter. Disclosure