By Arizona Department of Transportation
Several large Arizona Department of Transportation projects are set to get underway along Phoenix-area freeways in 2026, including the first projects funded under Proposition 479 approved by Maricopa County voters in 2024.
Substantial progress also will be made during the new year on two Proposition 400-funded widening projects along Loop 101 and Loop 202. Voters approved Proposition 400 in 2004. Here is ADOT’s overview of the Valley freeway project heading into 2026:
- Loop 303 Improvement Project between I-17 and 51st Avenue: This $129M project, scheduled to start by late January, will add direct freeway-to-freeway ramps at the I-17/Loop 303 interchange in north Phoenix. Crews also will widen Loop 303 to three lanes in each direction from I-17 west to 51st Avenue. It is the first project to be funded using Proposition 479 half-cent sales tax revenue managed under the Maricopa Association of Governments’ Regional Transportation Plan. It is scheduled to be completed in 2028. ADOT recently added a second northbound I-17 lane approaching and leading into the off-ramp at Loop 303, providing more capacity for traffic exiting during busy rush hours.
- Loop 303 Widening Project (51st Avenue to Lake Pleasant Parkway): This is a separate project west of the larger project near I-17 that also will widen Loop 303 to three lanes in each direction and add other improvements. It also will be funded via the MAG Proposition 479 Regional Transportation Plan. Work is scheduled to start by fall 2026.
- Loop 101 (Pima Freeway) Widening Project (Shea Blvd. to Princess Drive): New north- and southbound lanes along 4.5 miles of Loop 101 opened in November as part of this $108M project in Scottsdale. Construction began in January 2024. Substantial completion is scheduled in early 2026. Note: A separate project to improve the Loop 101 pavement surface during overnight restrictions (Shea to Princess) is scheduled to start in the spring.
- Loop 303 Improvement Project (Van Buren St to Maricopa County 85): This project in the West Valley will construct Loop 303 along four miles of the Cotton Lane corridor, providing three lanes in each direction between Van Buren Street and Lower Buckeye Road. Crews also will build two lanes in each direction between Lower Buckeye Road and MC 85. Preconstruction work, including utility relocation, is currently underway. The four-year project is scheduled to start by mid-2026.
- I-10/Loop 101 Interchange Improvement Project in the West Valley: A new elevated bridge will be added to carry HOV lanes between the two freeways (to and from downtown Phoenix area). The project will widen both I-10 and Loop 101 near the existing interchange. A separate ramp will be built to allow southbound Loop 101 drivers to make a direct connection to 91st Avenue south of I-10. Work is expected to start this spring and take approximately three years to complete.
- Loop 101 (Agua Fria Freeway) Widening Project (I-17 to 75th Avenue): Crews will continue work to construct new lanes in each direction along 6.5 miles of Loop 101 in the Northwest Valley. Other improvements are being made along freeway frontage roads. Another southbound 75th Avenue turn lane to eastbound Loop 101 will be added. The $140 million project started in September 2024 and is scheduled for completion in spring 2027.
- Loop 202 (Santan Freeway) Widening Project (Loop 101 to Val Vista Drive): The $200M project in Chandler and Gilbert is adding two lanes in each direction between Loop 101 and Gilbert Road. One lane in each direction will be added between Gilbert Road and Val Vista Drive. Freeway bridges are being widened. Work began in August 2024 and is scheduled for completion in spring 2027. (Source)