I-17 101 traffic interchange

Thermal cameras at Loop 101 ramps successfully detect wrong-way vehicles

Thermal cameras at Loop 101 ramps successfully detect wrong-way vehicles

September 11, 2017

PHOENIX – Thermal cameras now being tested for detecting wrong-way vehicles on freeway off-ramps in the Phoenix area successfully alerted authorities to two recent overnight incidents along Loop 101 (Agua Fria Freeway) in the northwest Valley.

Early Sunday, Sept. 10, a thermal camera being tested at the Loop 101 interchange at 75th Avenue detected a wrong-way vehicle entering the eastbound freeway. The detection triggered an alert to the Arizona Department of Transportation’s Traffic Operations Center, which activated warnings on overhead message boards, and to the Arizona Department of Public Safety. State Troopers stopped the vehicle on northbound 101 near Grand Avenue, and no crashes occurred.

Early Monday, Sept. 11, a thermal camera detected a vehicle apparently traveling westbound in the eastbound lanes of Bell Road that then made a wrong-way turn to the northbound Loop 101 off-ramp. ADOT and DPS were again alerted to the detection. Video from the thermal camera shows the driver turning around at the top of the ramp and apparently returning to Bell Road. State Troopers who responded didn’t locate the vehicle or driver.

ADOT recently programmed existing thermal cameras used for traffic-signal sequencing at 11 freeway interchanges to test detection of vehicles entering off-ramps in the wrong direction.

Testing of these thermal cameras is taking place while ADOT moves forward on the installation of a comprehensive pilot wrong-way vehicle detection and warning system along a 15-mile stretch of Interstate 17 in Phoenix. The system, scheduled to be fully operational by early next year, also will use thermal cameras to detect wrong-way vehicles in an effort to reduce the risk of serious crashes.

This testing is one way ADOT is moving toward expanding wrong-way countermeasures as quickly as possible beyond the I-17 prototype system currently being installed.

In addition to thermal cameras, the I-17 prototype system will use warning signs for wrong-way drivers and advisories for right-way drivers. The system will automatically focus highway cameras on the wrong-way vehicle and send automated alerts to the Highway Patrol, helping troopers intercept vehicles faster.

On the I-17 ramps, wrong-way vehicles will trigger alerts, including illuminated signs with flashing lights, aimed at getting drivers to stop. The system will immediately warn other drivers through overhead message boards as well as law enforcement. Cameras in the area will automatically turn to face the wrong-way vehicle so traffic operators can better track it. On the freeway, thermal cameras placed at one-mile intervals will signal when a wrong-way vehicle passes so State Troopers can plan their response and get out in front of the wrong-way driver, providing a faster response.