Innovative method will slide in new Fourth Street bridge in Flagstaff

Drivers can expect bridge closure, lane restrictions on I-40 for two weeks

PHOENIX – The Arizona Department of Transportation will use an innovative method to slide the new Fourth Street bridges over I-40 in Flagstaff into place later this month, cutting by months the time it would normally take to build a new bridge.

Installing the new bridges will require the closure of Fourth Street over Interstate 40 beginning at 8 p.m. Friday, July 17. The work will continue over the next couple of weeks and is scheduled to be completed early Monday, Aug. 3.

I-40 will be narrowed to one lane under the bridge at times during the bridge closure. Eastbound I-40 will be narrowed to one lane under Fourth Street at the following times:

  • 8 p.m. Friday, July 17, to 6 p.m. Saturday, July 18
  • 8 p.m. Tuesday, July 21, to 6 a.m. Thursday, July 23
  • 8 p.m. Thursday, July 23, to 12:30 a.m. Saturday, July 25

Westbound I-40 will be narrowed to one lane under Fourth Street at the following times:

  • 6 p.m. Saturday, July 18, to 6 a.m. Monday, July 20
  • 6 a.m. to 8 p.m. Thursday, July 23
  • 12:30 a.m. Sunday, July 26, to 6 a.m. Wednesday, July 29

This is not the first time ADOT has used the bridge slide method to install a new bridge. Last fall, this method was used to install the new Bellemont bridges at I-40 and Hughes Avenue, formerly Transwestern Road, west of Flagstaff. Workers used hydraulic jacks to lift and move the new Bellemont bridges into place after the old ones were demolished.

ADOT regularly looks for accelerated bridge construction methods and other innovations that can reduce delays and inconvenience for drivers.

For more information, visit and click on the North Central District.