Reversible lanes among possible improvements for I-17 north of Phoenix

PHOENIX – To reduce traffic backups from crashes, congestion and other incidents along Interstate 17 north of Phoenix, the Arizona Department of Transportation is evaluating options that include the possibility of reversible lanes on the grade between Black Canyon City and Sunset Point.

The reversible-lane concept (the video above shows an animation of what a system could look like) is among alternatives being considered to move more traffic while enhancing safety along that winding eight-mile stretch of I-17.

Regardless of whether reversible lanes become a reality, ADOT’s goals include expanding I-17 capacity along more than just those eight miles. As part of the state’s Key Commerce Corridors plan, which proposed investments in interstates and other highways to support economic growth, ADOT recommended widening I-17 to three lanes north of Anthem Way.

“I-17 is vital for passenger and commercial traffic between Phoenix and northern Arizona communities,” ADOT Director John Halikowski said. “We’re determined to identify options to increase the lane capacity along the highway while also working with the Department of Public Safety and other partners to reduce driver behaviors that lead to crashes and cause unnecessary delays. Drivers can be a big help in this effort by exercising patience and good judgment to improve safety in that area.”

With the State Transportation Board’s approval of ADOT’s five-year construction program last June, $3 million is being used this fiscal year for preliminary design work on alternatives for the corridor between Black Canyon City and Sunset Point. Another $5 million has been set aside in fiscal 2020 for final design.

A possible design for reversible lanes would feature a barrier at each end of the system that would be adjusted to open additional lanes in one direction of travel at any one time. For example, the lanes would be available for northbound traffic to use at the beginning of a weekend or available for southbound traffic on a Sunday afternoon or evening.

A preliminary design has estimated the construction costs for such a system at $125 million. While no funding is currently available for a reversible-lane system or widening projects, ADOT is aggressively seeking solutions including the possibility of a public-private partnership that could move a large project along sooner and at a lower cost.

More immediately, ADOT later this year will launch a safety-based project to add six electronic “speed feedback” signs along I-17 north of the Phoenix area. Those signs will display vehicle speeds while reminding drivers of the posted speed limit. ADOT’s project also will add four new electronic message signs to provide information about highway conditions along with safety messages.