New Loop 303 lanes open in northwest Valley

ADOT’s projects near completion between Grand Avenue, Happy Valley Parkway

PHOENIX – Drivers in the northwest Valley are using a wider stretch of freeway this morning after the Arizona Department of Transportation on Thursday opened new lanes along Loop 303 between Grand Avenue in Surprise and Happy Valley Parkway in Peoria.

In less than two years, this seven-mile stretch of Loop 303 has been improved from a four-lane highway to a safer freeway, with three travel lanes in each direction. The wider freeway is part of $96 million in projects that also added new Loop 303 interchanges at Grand Avenue and El Mirage Road.

This milestone also is part of a series of major Loop 303 projects that ADOT launched in 2009 to provide the West Valley with 35 miles of continuous freeway from Interstate 17 in north Phoenix to Interstate 10 in Goodyear. The projects are included in the Maricopa Association of Governments’ 20-year Regional Transportation Plan approved by Maricopa County voters in 2004.

In addition, Loop 303 serves as an integral part of the economic development plans of West Valley communities.

Crews working on the newest stretch of a wider Loop 303 completed their lane-striping work and opened the full complement of three new lanes in each direction Thursday. The roadway had been limited to one lane in each direction while recent work was underway. 

Temporary lane restrictions will be scheduled at times along Loop 303 between Happy Valley Parkway and El Mirage Road as part of final project work over the next few weeks, but no major traffic impacts are expected.

Here’s an overview of the three major ADOT projects that have improved Loop 303 in the northwest Valley:

  • Loop 303 Reconstruction Project between Grand Avenue and Happy Valley Parkway: $29.8 million project provided a wider stretch of Loop 303 and other improvements, including neighborhood sound walls adjacent to the freeway. Launched in August 2014, the project was finished in summer 2015. Final paving and lane striping in this area also was scheduled as part of the follow-on project to construct the new Loop 303/El Mirage Road Traffic Interchange.
  • Loop 303/Grand Avenue Interchange Project: $46 million project has reconstructed the interchange linking Loop 303 and Grand Avenue, adding a new northbound Loop 303 bridge and providing new on- and off-ramps connecting the roadways. Launched in December 2014, the project was opened to traffic this spring.
  • Loop 303/El Mirage Road Traffic Interchange Project: $19.9 million project allowed crews to build Loop 303 bridges over El Mirage Road while providing new on- and off-ramps connecting the two roadways. The project also completed final paving and lane-striping along Loop 303 between Grand Avenue and Happy Valley Parkway. Started in February 2015, the last of the work for the project will be completed this summer.

For more information about ADOT freeway projects in the Phoenix area and additional projects across Arizona visit