Traffic Alerts - Rio de Flag Bridge Replacement

Plan for week-long closure of Historic Route 66 in front of Flagstaff City Hall beginning June 10

Drivers should avoid the area, use alternate routes and allow extra travel time

The Arizona Department of Transportation is advising motorists who use Historic Route 66 (B40) in Flagstaff to plan for road closures as work continues on the Rio De Flag Bridge replacement project.

The following around-the-clock closures on Historic Route 66 (40B) will occur from 9 p.m. Thursday, June 10, through 6 a.m. Friday, June 18:

  • Eastbound travel lanes will be closed at Sitgreaves Street.
  • Westbound travel lanes will be closed at Humphreys Street.


  • Northbound Historic Route 66 (Milton Avenue) to northbound US 180 (Humphreys Street) traffic will be detoured to east Butler Avenue to north San Francisco Street to access north US 180 (Switzer Canyon Drive). 
  • Southbound US 180 (Humphreys Street) to westbound Historic Route 66 (B40) will be detoured to south Beaver Street to west Butler Avenue.
  • Detour signs will be in place to direct drivers around the closure.

Drivers on Historic Route 66 (B40) from east Flagstaff can use Switzer Canyon Drive to head north or use Ponderosa Parkway to head south and connect with Butler Avenue to continue west and south. Drivers traveling south on US 180 are encouraged to use Switzer Canyon Drive to Historic Route 66 to bypass construction-related traffic impacts.

Rio de Flag detour

Stay Informed!

ADOT will provide more information about project schedules and potential traffic impacts as information becomes available.

  • By email: Subscribe to receive project updates and traffic alerts.
  • By phone:  Call the ADOT Bilingual Project Information Line at 855.712.8530.
  • Online: Submit a question or comment through the ADOT website. Visit and then select Projects from the dropdown menu.
  • Twitter:  Follow ADOT on Twitter  (@ArizonaDOT) for real-time highway conditions statewide.