PHOENIX — The Arizona Department of Transportation has outlined several significant freeway improvement projects set to begin in the Phoenix area during 2026, including the first initiatives funded by Proposition 479, which Maricopa County voters approved in 2024.
Major progress will also continue on two Proposition 400-funded widening projects along Loop 101 and Loop 202. Voters approved Proposition 400 in 2004.
Loop 303 improvements lead 2026 projects
The largest project scheduled to start is the $129 million Loop 303 Improvement Project between I-17 and 51st Avenue, set to begin by late January. The project will add direct freeway-to-freeway ramps at the I-17/Loop 303 interchange in north Phoenix and widen Loop 303 to three lanes in each direction from I-17 west to 51st Avenue.
This marks the first project funded using Proposition 479 half-cent sales tax revenue managed under the Maricopa Association of Governments Regional Transportation Plan. The project is scheduled for completion 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.
A separate Loop 303 widening project from 51st Avenue to Lake Pleasant Parkway will also widen the freeway to three lanes in each direction. This project, also funded through the MAG Proposition 479 Regional Transportation Plan, is scheduled to start by fall 2026.
Several other significant projects are scheduled for 2026:
- Loop 303 Improvement Project (Van Buren Street to Maricopa County 85): This West Valley project will construct Loop 303 along 4 miles of the Cotton Lane corridor, providing three lanes in each direction between Van Buren Street and Lower Buckeye Road. Crews will also build two lanes in each direction between Lower Buckeye Road and MC 85. The four-year project is scheduled to start by mid-2026.
ADOT - I-10/Loop 101 Interchange Improvement Project: A new elevated bridge will carry HOV lanes between the two freeways to and from the downtown Phoenix area. The project will widen both I-10 and Loop 101 near the existing interchange and build a separate ramp allowing 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.
ADOT
Ongoing projects nearing completion
- Loop 101 (Pima Freeway) Widening Project: New north- and southbound lanes along 4.5 miles of Loop 101 opened in November as part of this $108 million project in Scottsdale. Construction began in January 2024, with substantial completion scheduled for early 2026. A separate project to improve the Loop 101 pavement surface during overnight restrictions from Shea to Princess is scheduled to start in the spring.
- Loop 101 (Agua Fria Freeway) Widening Project: Crews continue work to construct new lanes in each direction along 6.5 miles of Loop 101 in the Northwest Valley. The $140 million project started in September 2024 and is scheduled for completion in spring 2027.
- Loop 202 (Santan Freeway) Widening Project: The $200 million project in Chandler and Gilbert is adding two lanes in each direction between Loop 101 and Gilbert Road, with one lane in each direction between Gilbert Road and Val Vista Drive. Work began in August 2024 and is scheduled for completion in spring 2027.
This story was reported on-air by a journalist and has been converted to this platform with the assistance of AI. Our editorial team verifies all reporting on all platforms for fairness and accuracy.