Arizona”s thermal ramp cameras successfully detect wrong-way vehicles


The Arizona Department of Transportation (ADOT) has revealed that its thermal cameras, now being tested for detecting wrong-way vehicles on freeway off-ramps in the Phoenix area, have successfully alerted authorities to two recent overnight incidents along Loop 101 (Agua Fria Freeway).

ADOT recently programmed existing thermal cameras that are 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 (24km) stretch of Interstate 17 in Phoenix. The pilot system, scheduled to be fully operational by early next year, will also use thermal cameras to detect wrong-way vehicles in an effort to reduce the risk of serious crashes. ADOT says this current testing is one way that it 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, so traffic operators can better track it, 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.

ADOT reports that early on September 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 ADOT’s Traffic Operations Center, which activated warnings on overhead message boards, and to the Arizona Department of Public Safety (DPS). State Troopers stopped the vehicle on northbound 101 near Grand Avenue, and no crashes occurred.

In the second incident, on September 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 did not locate the vehicle or driver.

Share this story:

About Author


Tom has edited Traffic Technology International (TTi) magazine and its Traffic Technology Today website since May 2014. During his time at the title, he has interviewed some of the top transportation chiefs at public agencies around the world as well as CEOs of leading multinationals and ground-breaking start-ups. Tom's earlier career saw him working on some the UK's leading consumer magazine titles. He has a law degree from the London School of Economics (LSE).