Local News by Blake Herzog
The environmental assessment report for the widening of Interstate 10 between Casa Grande and Chandler has completed its first stages, providing a glimpse of what the project will add to increase the capacity and safety of the crucial 26-mile link through the Gila River Indian Community between fast-growing Pinal County and the Valley.
As presented online at
www.i10wildhorsepasscorridor.com and during a series of public hearings in September, at least one lane of traffic will be added in each direction on the freeway, for a total of six lanes across. High-occupancy vehicle (HOV) lanes will be added to the northern end of the stretch, between the Loop 202 (Santan Freeway) and Riggs Road.
Officials from the Arizona Department of Transportation (ADOT) said the median will be expanded for the full length of the project and barriers added to prevent crossover crashes. The shoulders will be widened to give drivers more room to pull off I-10 to further improve safety.
In addition, all five freeway interchanges along the segment would be upgraded and a sixth one added. Going from south to north:
- State Routes 387/187/Pinal Avenue — Crossroads will be widened and traffic lights will be added to both intersections. A new bridge just north of the existing one would be built to increase the traffic capacity while maintaining the basic configuration of the interchange.
- Seed Farm Road — A new diamond-style interchange is proposed about 3 miles north of the Sacaton rest stop at this road that leads to Sacaton to improve traffic flow within the Gila River Indian Community.
- State Route 587/Casa Blanca Road
—This interchange has tight, curving ramps and requires drivers on Casa Blanca Road to go through the interchange. The proposed redesign would turn it into a more conventional diamond interchange, but roundabouts would be installed to control traffic flow.
- State Route 347/Queen Creek Road — ADOT proposes to upgrade this interchange with a “diverging diamond” design, which uses two overpasses, one for each direction of traffic, crossing over the interstate while on the opposite side of where they would normally be. Officials say this configuration is safer and more efficient and will allow pedestrians and cyclists to cross over the freeway.
A second bridge would be built over the freeway to accommodate this design. A computer simulation of how drivers would use this interchange is available on the project website.
- Wild Horse Pass Road/Sundust Road — This intersection also would be converted into a diverging diamond configuration under ADOT’s plan.
- Loop 202 (Santan Freeway) — Because it already has six lanes, only the pavement striping and signage would be updated.
4-year construction timeline
Project Manager Carlos Lopez said during a Sept. 20 virtual meeting that all public comments submitted during the first phase of the environmental assessment process will be incorporated into the final report. It’s expected to be completed early next year and submitted to the U.S. Environmental Protection Agency, which must approve it before the project can move forward or qualify for federal funding.
The state has applied for $360 million of federal National Infrastructure Project Assistance, known as the Mega Grant Program, whose awardees are scheduled to be announced this fall. That would fully fund the projected $990 million when combined with $400 million allocated by the state Legislature and about $230 million from the Maricopa Association of Governments.
If all goes according to plan, construction is expected to begin in late 2023 and will take about 4 years to complete.
Lopez said alternative funding sources if the state doesn’t win the Mega grant are “to be determined. It would include all options including federal grants, future federal grants and other federal, state and local funding opportunities that could arise.”
He said the widening could also move ahead with partial funding,