Drivers who frequent I-17 and Loop 303 in North Phoenix are buckling up for big construction improvements as the Arizona Department of Transportation is just getting started on a two-and-a-half year widening project with direct connections between the two freeways.
The ramp from northbound I-17 to westbound Loop 303 will be built on an elevated flyover bridge that will travel above I-17, according to plans.
Addressing growing traffic demands on both freeways and new residential and commercial plans in the area, including TSMC’s growing campus expansion south of Loop 303 adjacent to Pulte’s proposed future NorthPark master-planned community, the project aims to ease traffic and eliminate the use of Sonoran Desert Drive for on-and-off access to Loop 303.
The $129-million project calls for widening Loop 303 to three lanes in each direction between I-17 and 51st Avenue, along with direct freeway-to-freeway ramps between Interstate 17 and Loop 303. The ramp from northbound I-17 to westbound Loop 303 will be built on an elevated flyover bridge that will travel above I-17, according to plans.
The project also includes new bridge construction to accommodate a future traffic interchange at 67th Avenue, along with new lighting, drainage improvements and new overhead signs.
Drivers can expect restrictions at times along I-17.
ADOT spokesman Doug Nintzel told Valley Vibe crews will start with bridge foundation work in the area of the I-17/Loop 303 interchange. He said a schedule of roadway restrictions is in the works, and is expected to be in place in February.
“We’re looking forward to getting the work underway,” Nintzel said. “So many people in recent years have asked ADOT about building the direct connections between the two freeways. We had to look to the day when funding would be available. It’s nice to know that has happened and we’re set to work with our partners to create an interchange where most drivers won’t stop at traffic signals but instead use the new free flowing ramps,” he added.
The project is slated to be completed in mid-2028. It is the first project funded under the voter-approved Proposition 479, a dedicated half-cent sales tax revenue managed under the Maricopa Association of Governments Regional Transportation Plan approved by county voters in the November 2024 election.
Widening Loop 303 to Lake Pleasant Parkway
ADOT and MAG also expect a sister project to widen Loop 303 (to 3 lanes in each direction) between 51st Avenue and Lake Pleasant Parkway to start in fall 2026, according to Nintzel.
New lane at NB I-17 off-ramp to Loop 303
At the end of 2025, ADOT added a second lane leading into and along the Northbound I-17 exit at Loop 303 allowing more vehicle capacity to ease the traffic backup on the freeway during peak travel hours.
| Stay Informed |
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| ADOT will provide information about planned closures on the project’s website at www.azdot.gov/L303LakePleasantI-17. ADOT Project Information Line 855-712-8530 Email Input & Questions projects@azdot.gov Projects Included Under Prop 479 www.azmag.gov/prop479 |
By Karen Goveia
editor@valleyvibenews.com