I-17 101 traffic interchange

Rapid legislative action commits $400 million to address I-10 congestion between Phoenix and Casa Grande

Rapid legislative action commits $400 million to address I-10 congestion between Phoenix and Casa Grande

May 4, 2022

PHOENIX - Approval of a $400 million appropriation by the Arizona legislature means the Arizona Department of Transportation can now submit a grant request for an additional $300 million in federal money for a proposed project to alleviate long standing traffic congestion on Interstate 10 between Chandler and Casa Grande.

Governor Doug Ducey has signed legislation sponsored by Senator T.J. Shope (R) - Coolidge.  It appropriates $400 million for this proposed project that was first outlined in the Governor’s fiscal year 2023 budget proposal. This would accelerate the expansion of this congested 26-mile stretch of I-10, the last segment of I-10 between Phoenix and Tucson that has not been widened from two lanes to three lanes. The project also would include widening and improving several interchanges, cross roads and bridges, including the bridges over the Gila River. The state appropriation also is necessary to present a grant application made possible through the federal Infrastructure Investment and Jobs Act (IIJA) legislation.

"This funding is a tremendous moment for Arizona motorists and all the out-of-state drivers who use this vital stretch of highway,” said Governor Doug Ducey. “Commuters, visitors and commercial traffic will face fewer frustrating bottlenecks in this area of I-10. This new funding sets in motion the process to expand the highway and put the congestion in the rear-view mirror. It also will boost business, jobs and quality of life in our state.”

“ADOT is tremendously grateful to Governor Doug Ducey, Senator Shope and his legislative colleagues for their quick and decisive action to secure these funds,” ADOT Director John Halikowski said. “Collaboration with the Gila River Indian Community has also been critical, as well as working with the Maricopa Association of Governments, our industry partners and other stakeholders. This has been a true team effort. We now can move forward on competing for federal grant money to fully fund the much-needed widening of I-10.”  

An engineering and environmental study for the project is currently being completed in cooperation with the Gila River Indian Community and MAG and includes the following proposed improvements:

Corridor Improvements - Capacity and Safety:

  • Adding a new general purpose lane in east and westbound directions, extending the High Occupancy Vehicle (HOV) Lane on I-10 from Loop 202 to Riggs Road, and improving interchanges and crossroads will increase capacity and access. This improves safety by reducing congestion and travel times and lessening detoured traffic on the Gila River Indian Community.
  • Replacing bridges over the Gila River will maintain a state of good repair by modernizing this key infrastructure. 
  • Building new and improved traffic interchanges creates safer crossings for farm equipment, bicyclists and pedestrians and boosts connections and quality of life. 
  • Installing fiber optic infrastructure within ADOT Right-of-Way will allow for the installation of sensors, cameras and other highway safety-related technology.

Key Commerce Corridor, Arizona Jobs and Local Connections:

  • As the principal roadway between metro Phoenix and Tucson for commuters, cross-country travelers and commercial traffic, I-10 is a Key Commerce Corridor for Arizona and the U.S. It provides a vital link for freight traffic from the ports of southern California and for international commerce, with a significant amount of freight transported along the route daily. The proposed improvements will improve the reliability of freight traffic in the corridor.
  • The project, coupled with others around the state, will help attract employers and create jobs in Arizona.
  • Locally, the route serves the Gila River Indian Community by providing connections to employment, medical, educational, and other critical services both within and outside of the Community. 


  • Total estimated project cost is approximately $990 million.
    • $400 million allocated in the state budget
    • $300 million to be requested as a federal grant
    • $290 million previously budgeted. 
  • Construction for the I-10 widening project is funded in part by Prop. 400, a dedicated half-cent sales tax approved by Maricopa County voters in 2004. 


  • A public hearing for the project is planned in late summer.
  • Following completion of required environmental review and clearance, the project is expected to start in 2023, beginning with expanding the bridges that carry traffic over the Gila River. 
  • Target completion date for the full project is sometime in 2026.

For more information: http://i10wildhorsepasscorridor.com/.