Technology helping ADOT to manage traffic through I-15 bridge project

Alerts drivers to traffic conditions through northwestern Arizona work zone

PHOENIX – To enhance safety and manage traffic through the bridge improvement project along Interstate 15 in the Virgin River Gorge, the Arizona Department of Transportation is using a first-of-its-kind alert system to help reduce emergency braking and collisions.

With I-15 reduced to one lane in each direction during construction, traffic begins to queue during peak travel times and holidays. A queue warning system that includes portable message boards informs drivers of stop-and-go traffic ahead using equipment that detects traffic in real-time. 

With advance notice, drivers can anticipate heavy traffic, slow down and avoid erratic behavior, helping reduce collisions in the queue.

While this is the first time the system has been used on an ADOT project, going forward the agency intends to use it on projects creating similar traffic conditions.

The $6.4 million bridge improvement project is resurfacing the decks of Bridge No. 2 and Bridge No. 5 in I-15, while Bridge No. 4 is receiving a new deck. 

The project is scheduled to wrap up next spring.

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