The Arizona Department of Transportation (ADOT) reports significant progress on the I-10 Wild Horse Pass corridor project, with construction of new eastbound bridges over the Gila River advancing on schedule. The $964 million project will widen a 26-mile stretch of I-10 from the Loop 202 San Tan/South Mountain Freeway to just south of State Route 387 near Casa Grande, adding a third general-purpose lane in each direction to alleviate congestion on this critical transportation corridor.
“Construction on all four segments of the project should be completed by 2028,” said Marcy McMacken, ADOT’s Community Outreach Project Manager, during a recent interview on ADOT’s “On the Road” podcast.
Impact on Drivers
ADOT has designed the construction to minimize disruption to the approximately 63,000 vehicles that travel this section of I-10 daily, according to 2022 ADOT reports.
“Motorists will be happy to hear that during this construction project there will be no full freeway closures in either direction while the construction work is taking place to widen this section of I-10,” McMacken said. “We will have a few overnight lane restrictions but those will happen mostly during the week and not on weekends.”
The project has been specifically planned to maintain traffic flow while construction takes place adjacent to existing lanes. During peak travel times, it currently takes an average of 33 minutes to drive through this 26-mile segment, ADOT reported in 2022. Without improvements, this would increase to 40 minutes by 2040. With the widening project completed, travel time is projected to reduce to approximately 32 minutes in 2040, even with increased traffic volumes.
Impact on Gila River Indian Community
“We are working very closely with the Gila River Indian Community,” McMacken explained. “This project extends through the Gila River Indian Community and it’s important for them because it connects their community members to services such as medical, educational and employment services within their community and outside of their community.”
Approximately 81 acres of new right-of-way for interchange and crossroad improvements will be needed on the Gila River Indian Community. ADOT is working closely with the Community and the Bureau of Indian Affairs on easement acquisition processes.
The completed project will have additional benefits for the Community, as the improved capacity will decrease the number of times the freeway would need to be closed or restricted due to accidents or construction, reducing cut-through traffic on Community roads.
Project History
The I-10 corridor between Phoenix and Tucson has been expanded in segments since approximately 2005. By 2019, I-10 consisted of three lanes in each direction between SR 387 near Casa Grande and Tucson, leaving only the 26-mile stretch across the Gila River Indian Community as the only remaining section with two lanes in each direction.
In summer 2019, ADOT and partner agencies began studying ways to increase capacity on this final two-lane section. The project planning phase continued through early 2024, with the Gila River Bridge replacement project developed as a separate but coordinated effort.
Project Timeline and Segments
The project is being implemented in four distinct segments, allowing for a phased construction approach that minimizes traffic disruption:
I-10 Bridges Over the Gila River (MP 172-174): This segment is already under construction, having begun in May 2024. It includes replacing the existing two-lane bridges with new three-lane bridges with wide shoulders. Completion is scheduled for 2026 at a cost of approximately $71.2 million.
I-10 Gasline Road to South of SR 387 (MP 177-187): Construction on this southernmost 11-mile segment is set to begin later this year. “Construction on the most southern end of the project is going to begin and that’s the 11-mile structure of I-10 that starts at I-10 and Gasline Road and it ends just north of Casa Grande or south of State Route 387,” McMacken stated. This segment will cost approximately $267.9 million and includes a new interchange at Seed Farm Road.
I-10 Gila River to Gasline Road (MP 174-177): This segment will add a third general-purpose lane in each direction and reconstruct the existing interchange at Casa Blanca Road/SR 587. Construction is anticipated to begin in late 2026 with an estimated cost of $158.4 million.
I-10 Gila River Indian Community Project (MP 161-172): The northernmost 10-mile segment will begin construction in 2026. It includes adding a third general-purpose lane and extending HOV lanes from Loop 202 to Riggs Road. Construction of this project is estimated to cost approximately $430 million.
Economic Impact
“This structure of I-10 is critical for Arizona’s economy. It not only connects the states largest metropolitan cities but it also provides a key link for transportation of national and international freight and goods,” McMacken said in the interview. “It’s also important for Arizonans who live in rural communities. They use this route to travel to and from Phoenix or from Phoenix and Tucson.”
The I-10 corridor serves as a pipeline for the movement of goods locally, regionally, nationally, and internationally. Maintaining an operational interstate is paramount for the movement of these goods and services. When completed, the widening project will reduce travel times, improve safety, and enhance freight movement efficiency, supporting economic growth throughout the region.
Looking Ahead
As construction progresses on the I-10 bridges over the Gila River, motorists can anticipate work beginning on the southernmost segment later this year. The completion of this project by 2028 will provide I-10 drivers with three continuous travel lanes in each direction between Phoenix and Tucson for the first time.
In addition to the extra travel lanes, the project includes significant safety improvements. The addition of wide inside and outside shoulders will help mitigate run-off-road crashes and facilitate emergency vehicle response. The entire corridor will feature freeway management systems including sensors, cameras, variable message signs and other highway operations and safety-related technology.
For updates on the I-10 Wild Horse Pass Corridor project, ADOT encourages drivers to visit i10wildhorsepasscorridor.com.
