Holiday traffic on Interstate 17 north of Phoenix often becomes an exercise in patience and frustration. Now help and additional lanes are on the way for one of the busiest freeways in Arizona.

The Arizona Department of Transportation has selected a developer to improve that stretch of highway, but relief is still down the road.

Northbound traffic on I-17 between Anthem and Sunset Point at the start of a three-day weekend is stop and go, and often more stop than go. Heading back at the end of the holiday is much the same.

ADOT has announced an agreement with Kiewit-Fann Joint Venture to design, build, operate and maintain the Interstate 17 Improvement Project.

The cost for the 23-mile stretch will be about $446 million. That will include 15 miles of road widening, bridge replacements and an eight-mile flex lane system. The flex lanes will be able to carry heavy northbound traffic on a Friday or heavy southbound traffic on a Sunday.

Construction is scheduled to start in 2022 and is expected to take three years.

Arizona Department of Transportation