I-17 101 traffic interchange

State Route 89A switchbacks to close for up to five weeks after Memorial Day

State Route 89A switchbacks to close for up to five weeks after Memorial Day

April 15, 2014

PHOENIX — On arguably one of the most narrow and winding roadways on the state’s highway system, the Arizona Department of Transportation will soon begin a project that will restore the pavement along a three-and-a-half-mile segment of State Route 89A through the Oak Creek Canyon switchbacks.

Beginning on Monday, April 21, crews will start work on the $2 million improvement project that will repave the roadway between Pine Flat Campground and Oak Creek Vista overlook (mileposts 387-390). The project area is located in the Coconino National Forest midway between Sedona and Flagstaff, just north of the popular tourist destinations in Sedona and Oak Creek Canyon.

In order to complete the work in safe and timely manner, a full closure of SR 89A through the switchbacks, which have steep grades with little to no shoulders, will be necessary for up to five weeks following the Memorial Day holiday and prior to the Fourth of July holiday (May 27 – July 2). While the closure isn’t expected to last more than five weeks, ADOT is offering incentives to the contractor to complete the work as quickly as possible, while focusing on safety and quality. During construction, access will be maintained for emergency vehicles.

During the first phase of the project from April 21 through May 22, a single-lane restriction during daytime hours will be required Monday through Thursday throughout the project length as crews begin preparations for a full closure of SR 89A. The roadway will be open, without lane restrictions, during the Memorial Day weekend, May 23-26.

During this time, access will remain open to Pine Flat Campground and Oak Creek Vista overlook, although flaggers will be present to guide traffic through the work zone. Delays are possible. There will be no restrictions during weekends, holidays, or at night prior to the full closure when there will be no public access.

The timeframe for the full closure from May 27 to July 2 was chosen because it’s the most favorable time to apply the new pavement, which is temperature sensitive, and it’s before monsoon season, when rain can delay paving.

In addition to removing and replacing the existing asphalt, crews will also make repairs to the surface of the historic Pumphouse Wash Bridge and perform rockfall mitigation work in this area, which is prone to rockfalls.

The full closure will allow crews sufficient space to safely perform rock scaling work, which involves workers rappelling from a cliff and using hand tools to remove loose rocks that could potentially fall onto the roadway and injure motorists or damage the roadway.

For Sedona and the Oak Creek Canyon area, it is business as usual during this time because the project is located north of these popular destinations.

During the closure, the recommended detour from Sedona to Flagstaff will be to take State Route 179 to Interstate 17. The detour could add up to an extra half an hour of travel time for motorists who are commuting between Sedona and Flagstaff.

“ADOT understands that some residents and businesses will be inconvenienced during construction, but if this project was done under any other traffic control condition, it would extend the project several months longer, not to mention it would overshoot the ideal temperature window for paving,” said Flagstaff District Engineer Audra Merrick. “In addition, the full closure of SR 89A will allow us to maintain access for emergency responders, at all times, which is especially critical during wildfire season.

“Rest assured, ADOT is working with the contractor to complete the project as soon as possible, and has provided the contractor monetary incentives to complete the project ahead of the scheduled five-week closure.”

During the full closure, access will be maintained at either end of the full closure to allow entry to both Pine Flat Campground on the southern end and Oak Creek Vista overlook at the northern end.

Signage and message boards are currently being used in advance of the closure to ensure traffic is properly detoured via SR 179 to I-17.

For more information on the project, please watch our video with information on the SR 89A switchbacks project.