The safe-driving tips and resources at FocusOnDriving.com inform motorists about how to stay safe on Arizona’s roads.

I-17 ramp meters

ramp meter red light

Phoenix-area drivers are used to seeing freeway entrance-ramp meters with alternating green and red traffic lights during weekday rush hours. But some of the red lights in Interstate 17 ramp meters also play a role as part of the pilot wrong-way vehicle detection system being tested by the Arizona Department of Transportation.

When a wrong-way vehicle is detected by the thermal camera-based technology now in place along 15 miles of I-17 in Phoenix, the system also turns on the red lights in nearby entrance ramp meters to try to hold “right-way” traffic from entering the freeway.

While most drivers aren’t used to seeing a solid red light displayed by a ramp meter for more than a few seconds, ADOT wants I-17 drivers in Phoenix to know there is a reason for that to happen – a wrong-way vehicle may be ahead on the freeway. More information on this is available ADOT Website.