Project Information (Loop 202 South Mountain Freeway)

Project Information (Loop 202 South Mountain Freeway)

Loop 202 South Mountain Freeway

Project Information

For the largest project in State history, ADOT partnered with a private developer (Connect 202 Partners) to design, build, and maintain the freeway for 30 years. The design, build, maintain (DBM) delivery model is an innovative approach used nationwide to efficiently reduce the cost to taxpayers without sacrificing quality.

Now that the freeway is completed, the developer is responsible for maintaining the freeway and ensuring the safety of the traveling public for 30 years, which results in the developer constructing a freeway with the highest possible quality.

What does this mean for the public? In short, it means ADOT’s partnership with Connect 202 Partners results in taxpayers receiving a freeway that opened to traffic within three years, as construction occurred concurrently in four segments. ADOT delivered the South Mountain Freeway three years sooner through this innovative delivery method.

Loop 202 South Mountain Freeway - By the Numbers Infographic

South Mountain Freeway DDI

The 22-mile South Mountain Freeway includes two half diverging diamond interchanges, commonly known as DDIs. These interchanges, located at Desert Foothills Parkway and 17th Avenue, are the first of their kind in the state.


A DDI is a simple design innovation that addresses congestion and safety by allowing vehicles to travel more efficiently through an interchange. A DDI increases traffic flow by temporarily transitioning traffic to the left side of the road, allowing through-traffic and left-turning traffic to proceed through the interchange simultaneously, eliminating the need for a signalized left turn.

Learn more about DDI

South Mountain Freeway DDI Flyer cover