How it works

He said traffic signals are timed to provide enough green-light time to allow all the vehicles in the queue to pass through the intersection.

About 85 percent of all Austin intersections have vehicle-detection technology—through either cameras and/or in-ground inductive loop detectors, Goldberg said. The cameras view the signal approach and monitor if a vehicle enters a set zone, he said. A loop detector includes a metal loop, or wire embedded in the pavement, that detects anything magnetic—such as a vehicle or bicycle—that drives over it, he said.

When a vehicle is detected on a side street to a main thoroughfare, the monitoring system receives an alert that vehicles are approaching and notifies the signal more green time is needed on the side street to allow the vehicles to pass, Goldberg said. The advantage to using this is the signal will know when it should give green time to traffic on the side street and when it should give it back to the main street, he said.

Distracted driving takes away time from vehicle approaches that need green time, leaving frustrated drivers waiting for the next green light, Goldberg said.

“When I’m looking at a signal, I’m looking at the side street to see if it’s getting enough time,” he said. “We have these loops set up that are detecting vehicles, and in certain situations the first two vehicles may go and they’ll clear off the loop and then the signal thinks, ‘There’s no one here anymore—let’s give the time back to the major street.’ But there’s still a queue of 20 cars that haven’t cleared yet.”

Goldberg said distractions not only include texting but also drivers talking to their children, putting on makeup or trying to find a radio station.

He said the distracted driving issue exists “all over town.”

Goldberg is not just a city traffic engineer—he is also an Austin driver.

“I’m sure if I was in that line [of vehicles behind a distracted driver], I would be really upset that I didn’t get to get through and then think, ‘Oh, the signal’s not working right—I better call [the city information center telephone number] 311 and report this,’” Goldberg said. “Hopefully, by raising awareness about [distracted driving issues], we can help people know that they have a part in making sure traffic in Austin is moving efficiently.”