South Mountain Freeway construction to ramp up in 2018

Arizona’s largest single highway project ever on schedule to open by late 2019

PHOENIX ‒ One year after major construction began on the Loop 202 South Mountain Freeway, bridges have been built from the ground up, a massive amount of earth has been moved and compacted, and an emerging I-10 interchange has changed the West Valley skyline.

South Mountain Freeway deck pour at sunsetThe South Mountain Freeway is more than 35 percent complete from design to utilities to right-of-way acquisition to construction. Work is currently underway in all but one section of the 22-mile corridor. To date, crews have installed 8 miles of drainage pipe, moved 3.6 million cubic yards of dirt and used 2,900 tons of rebar manufactured from recycled steel.

In 2018, construction will expand as the Arizona Department of Transportation moves toward opening the freeway by late 2019.

Work is scheduled to begin this spring in the Center segment, a 3-mile stretch between 51st Avenue southeast and 32nd Lane.

This week, ADOT and Connect 202 Partners, the developer responsible for the design and construction of the South Mountain Freeway, detailed construction for the first half of 2018 with the corridor’s third semiannual construction notice, which is available at (click Construction Info).

Some of the 2018 highlights include:

I-10 segment (I-10 Papago to Lower Buckeye Road and improvements to I-10 between 43rd and 75th avenues)

  • Constructing new access roads parallel to I-10 between 51st and 67th avenues  that will replace direct freeway access at 59th Avenue
  • Continuing construction of an I-10 interchange with six ramps, including two direct HOV lane connections
  • Completing the bridge over Roosevelt Street

Salt River segment (Lower Buckeye Road to 51st Avenue)

  • Opening an Elliot Road bridge over the freeway alignment
  • Starting Estrella Drive interchange construction, which will require a 150-day closure of Estrella Drive between 51st and 59th avenues
  • Completing two half-mile-long bridges, the longest of project, over the Salt River (by end of 2018)
  • Constructing a bridge at Baseline Road and 61st Avenue

Center segment (51st Avenue to 32nd Lane)

  • Conducting pre-construction work, including plant salvage and geotechnical investigations (starting in early 2018)
  • Starting controlled rock blasting along two ridges on southwestern edge of the South Mountain Park to break large rock into smaller, more manageable pieces

Pecos segment (32nd Lane to I-10 Maricopa/Loop 202 Santan Freeway)

  • Detouring traffic on Desert Foothills Parkway for bridge construction
  • Completing bridges at 17th Avenue and 40th Street and continuing construction of bridges at 24th and 32nd streets, work that will require some weekend and night closures of cross streets
  • Beginning work on freeway paving (by late 2018)
  • Completing controlled rock blasting along Pecos Road between Desert Foothills Parkway and 24th Street to break large rock into smaller, more manageable pieces (through mid-2018)

Salt River Bridge Installation on South Mountain Freeway ProjectThe South Mountain Freeway will provide a long-planned direct link between the East Valley and West Valley and a much-needed alternative to I-10 through downtown Phoenix. Approved by Maricopa County voters in 1985 and again in 2004 as part of a comprehensive regional transportation plan, the South Mountain Freeway will complete the Loop 202 and Loop 101 freeway system in the Valley.

You can learn more about the South Mountain Freeway project and sign up for updates and weekly traffic alerts by visiting