PHOENIX - To promote safety on a 20-mile segment of Interstate 10 between Phoenix and Casa Grande, the Arizona Department of Transportation in collaboration with the Department of Public Safety is installing new signage that will restrict heavy vehicle truck traffic on this busy section of highway. Truck traffic will be restricted to the right lane only.

The signs are an interim safety measure along the final two-lane stretch of I-10 between Phoenix and Tucson that has yet to be widened to three lanes in each direction.

This segment has safety concerns due to heavy traffic flow and truck traffic. The right-lane restriction for heavy vehicle truck traffic is intended to help reduce crashes, along with the resulting delays and closures due to these incidents.

Based on data for the area where the signs are being posted, heavy vehicles were involved in about 20 percent of crashes and 15 percent of rear-end and sideswipe crashes.

The signs are intended to be in place until an improvement project kicks off to widen this segment of I-10. The first step is expected in 2023 with the replacement of bridges that carry traffic over the Gila River, following required environmental review and clearance. Also, ADOT is working closely with the Gila River Indian Community and the Maricopa Association of Governments to secure federal funding, to add to committed state funding, for work that could be completed as early as 2026.

The signs restricting heavy vehicle truck traffic to the right lane only are similar to those that ADOT has employed elsewhere, including I-17 north of Black Canyon City. Sign installation began Monday and is expected to continue through this week.

ADOT has worked to coordinate the interim safety measure with the Arizona Department of Public Safety and the Arizona Trucking Association. As is the case with other traffic control measures, ADOT will closely monitor traffic operations now that the signs and right-lane restrictions are in place.

For more information about plans to widen I-10 between Phoenix and Casa Grande, please visit http://i10wildhorsepasscorridor.com/.

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. 

Funding: 

• 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. 

Timeline: 

• 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/.

What takes 11 hours to empty, weighs just over 2,000 tons and can cover a football field half a foot deep? It's the 1,000 cubic yards of concrete that was poured over the weekend in conjunction with the Arizona Department of Transportation's Interstate 10 Broadway Curve Improvement Project.

On Saturday, I-10 Broadway Curve Improvement Project crews completed a critical step for the foundation that will support the new Broadway Road bridge that is being constructed over I-10. They poured 1,000 cubic yards of concrete to create what is called a “bridge footing.” This footing is a large concrete slab that will play an important role in the support and distribution of weight for the new bridge. 

The new bridge over I-10 is one of several bridges being replaced or widened as part of the I-10 Broadway Curve Improvement Project. Crews will take down the existing Broadway Road bridge after the new one is completed later on in the project. 

For more information on the I-10 Broadway Curve Improvement Project, visit https://i10broadwaycurve.com/  

To see video of the concrete pour: https://vimeo.com/669560984

TUCSON - All lanes of the Houghton Road interchange at Interstate 10 are now open as the Arizona Department of Transportation has completed a new kind of interchange for southern Arizona.

The $24.4 million project features a diverging diamond interchange, an innovative design that will improve safety and traffic flow in a rapidly growing part of southeast Tucson.

Unlike a traditional diamond interchange, each direction of Houghton Road traffic temporarily shifts to the left while crossing the freeway. This allows for left turns onto the entrance ramps without waiting at an additional traffic signal. The design also promotes safety because drivers turning left don’t cross traffic while entering the on-ramp. Signals, signs and pavement markings help guide drivers through the interchange.

The interchange features larger entrance and exit ramps, along with more space for traffic to merge onto I-10 westbound. Over the freeway, the old two-lane Houghton Road bridge has been replaced with a structure that features six lanes and improved access for pedestrians and bicyclists.

ADOT traffic engineers chose the diverging diamond design because it can handle higher traffic volumes in the growing part of the southeast Tucson area, where traffic is expected to increase by as much as 50 percent by 2045.

ADOT minimized traffic disruption by keeping most of the interchange open during the project, which began in August 2019. 

While all lanes are open, intermittent lane restrictions are possible in the next two weeks as construction crews wrap up minor project details. In the spring, drivers should expect overnight lane restrictions when warmer overnight temperatures allow for final paving on I-10 and the ramps.

More than 115 diverging diamond interchanges are in use in the U.S., including two half-diverging diamond interchanges on the Loop 202 South Mountain Freeway and a full diverging diamond interchange I-17 and Happy Valley Road in Phoenix.

More information about the I-10/Houghton Road project, including animations showing how to drive through a diverging diamond interchange, is available at azdot.gov/i10Houghton. 

The Arizona Department of Transportation and the city of Willcox are asking for the public’s feedback through the end of November on two potential traffic circulation changes to reduce the impact of freight traffic while improving safety in downtown Willcox.

The two options were identified as part of an ongoing traffic circulation study and public feedback from a community survey conducted in August 2021. The study looked at current and projected heavy truck traffic that flows between Interstate 10 and the industrial area on the southeast side of the city. Currently, the only way for heavy trucks to get between those areas is along State Route 186 through downtown Willcox, creating congestion and slowing the movement of freight.

After evaluating six possible alternatives to improve traffic flow and safety, ADOT identified two preferred alternatives for further evaluation and has begun a second community survey that runs through Tuesday, Nov. 30. Public input will help ADOT determine whether to move forward with either of the options or to make no changes. This analysis is in the study phase and no funding has been allocated for construction. This analysis is in the study phase and no funding has been allocated for construction.

The options are:

An interim, short-term project that would modify Haskell Avenue (Business 10) at the intersection with Maley Street (SR 186) to remove the left-turn lanes to provide more space for trucks to turn. Left turns would instead be made from one lane that is shared by through traffic, left turns and right turns. This option would also eliminate the existing traffic signal and convert the intersection into a four-way stop.

A longer-term solution that would construct a new bypass roadway east of downtown Willcox. The road would link Maley Street at 2nd Avenue to Haskell Avenue at Rex Allen Drive, including a new at-grade railroad crossing.

The public can find the community survey at /planning/transportation-studies/willcox-circulation-study. A paper version is available at the following locations during regular business hours:

Willcox City Hall, 101 S. Railroad Ave. B

Elsie S. Hogan Community Library, 100 N. Curtis Ave.

The survey is available in both English and Spanish. All comments must be received by Tuesday, Nov. 30.