Up to five full daytime closures from 6 a.m. to 4 p.m. Sunday mornings through Thursday evenings at the south end (MP 375) and up to 10 overnight full closures from 9 p.m. to 6 a.m. Sunday nights through Friday mornings at the north end (MP 387-389) of the project. The closures may be on consecutive or non-consecutive days.
Access will be maintained to properties in Oak Creek Canyon throughout the project. During the limited full closures on SR 89A, it may take longer to get to and from properties in the canyon since a detour will be in place. During the closures, property access to and from SR 89A will be maintained with detours either to the north or the south via SR 179 and I-17.
Construction is expected to start early this spring and be completed by the end of 2023. SR 89A will remain open to traffic with the exception of limited daytime and overnight closures. Once construction starts, the highway will be narrowed to one lane only through the work zone(s) with alternating northand southbound travel. Traffic-control will be maintained using a combination of temporary traffic signals and/or a flagging operation. ADOT is committed to completing the improvements as quickly as possible, while balancing the transportation and access needs of local communities.
The nature of the SR 89A corridor and the type of work being performed required extensive coordination with area public and private agency partners to determine how best to construct these projects, while minimizing impacts to drivers and canyon residents and businesses.
We discussed the pros and cons of two construction approaches:
Completely closing the north end of Oak Creek Canyon, which would get the improvements completed sooner, but with more driver and local impacts.
OR
Leaving SR 89A open with a single alternating north- and southbound travel lane through the work zones and limited full closures, but with a longer project duration.
After studying possible construction options and obtaining input from our agency stakeholders, ADOT decided to keep SR 89A open during construction with lane restrictions and limited closures for work that cannot safely be done around traffic. In February 2022, the Arizona State Transportation Board awarded the $11.1 million construction contract to Fisher Sand and Gravel Company.
All three improvements are vital to preserve the integrity and safety of State Route 89A. The highway was built in a canyon with a lot of rock-cut faces, which erode over time due to weather conditions. This leads to large rocks, sediment and other debris on the roadway, which creates significant safety and maintenance issues. The improvements include:
The Rockfall Mitigation improvement will help reduce the potential of large rocks falling onto the roadway at two locations along SR 89A. There have been several previous emergency closures due to rockfall events blocking the roadway.
The Drainage & Sediment Control improvement will reduce erosion to preserve deteriorating slopes and reduce downstream pollution as well as minimize or prevent future unplanned closures of SR 89A due to sediment or rocks blocking the roadway. In addition, the Pumphouse Wash Bridge Rehabilitation improvement is needed to maintain the structural integrity of the bridge, which is past its service life.
In summary, the improvements are needed to continue maintaining safety and access for motorists along SR 89A in Oak Creek Canyon.
No, this freeway is not tolled and is funded by state, federal, and local dollars.
Ports of entry monitor all commercial traffic entering Arizona for registration, taxes, size and weight restrictions, commercial driver license requirements, insurance requirements and equipment safety requirements, and issue permits as required. ADOT’s Enforcement and Compliance Division further works to ensure the safe and efficient movement of commercial motor vehicles on highways throughout Arizona.
Arizona highways, like most highways across the United States, are open to all kinds of traffic, so long as the cargo being carried is in accordance with U.S. Department of Transportation regulations for the specific type of cargo. The Arizona Department of Transportation has a few locations in the state with hazardous cargo restrictions, but these restrictions are based on emergency response issues or roadway design limitations specific to that location. For example, the Interstate 10 Deck Park Tunnel has certain hazardous cargo transport restrictions because of the limited ability for emergency responders to address a hazardous materials incident in the tunnel. The South Mountain Freeway will operate under the same rules as other similar facilities in the state; transport of hazardous cargo will be permissible.
The SMF was not constructed to create a "truck bypass" for downtown Phoenix. The freeway is part of a transportation system developed to improve mobility in the region by increasing capacity and providing traffic alternatives—including truck traffic—to other, already congested routes. As with all other freeways in the MAG region, trucks use the SMF for the through transport of freight, for transport to and from distribution centers, and for transport to support local commerce. It is anticipated that “true” through truck traffic (not having to stop in the Phoenix metropolitan area) would continue to use the faster, designated, and posted bypass system of I-8 and State Route 85. Also, like other “loop” freeways in the Phoenix metropolitan area, the SMF would be a commuter corridor, primarily serving automobiles and helping to move local traffic between the eastern and western portions of Maricopa County.
Factors considered in the environmental study were the amount of truck traffic that would use the freeway and its potential impact on the surrounding community. The MAG regional travel demand model forecasts approximately 10 percent truck traffic on the South Mountain Freeway in 2035. The forecasted truck traffic is based on existing traffic studies and projected socioeconomic data. This percentage is similar to current traffic conditions on I-10 between Loop 101 and I-17 and on US 60.