It took nearly three decades and $400 million, but traffic lights in Los Angeles have a brain. The Automated Traffic Surveillance and Control system has coordinated every one of the 4,500 traffic signals in the City, a move that already is showing increased efficiency in the daily commute.

According to the City, drivers’ average speeds have increased 16 percent with the help of the synchronized lights, and delays at the busiest intersections is down 12 percent. Before the system was implemented, it took 20 minutes to drive 5 miles on city streets, that time has been reduced to 17.2 minutes.

The system uses magnetic sensors buried under roads and cameras to monitor traffic flows. That data is then sent to city computers which analyzes the information second-by-second and compares it to past records. The system will even take into account ethnic factors – such as extending walk lights for pedestrians in Jewish neighborhoods on Saturdays.

The system is the first of its kind to be deployed in a citywide application in the United States.

Read the full story at the New York Times.