43rd Ave & SR 531 (172nd St) Roundabout

Project Description

Amazon.com Services, LLC will be constructing a roundabout at the intersection of 43rd Avenue NE and 172nd Street NE to improve vehicle safety and mobility through the intersection and the 172nd Street corridor. 

Additional benefits include improved pedestrian crosswalks, illumination, and a new trail from 43rd Avenue NE to 51st Avenue NE. 

This is being designed in coordination with the Department of Transportation’s corridor improvement project along 172nd Street from this intersection to 67th Avenue.

Click here to receive email updates on this project.

Click here to view WSDOT SR 531 Widening Project Page.  

Project Benefits

  • Increased pedestrian & vehicle safety
  • Improved mobility
  • Add multi-use trail

Project Funding

  • Funded by: Amazon,com Services, LLC
  • Coordinated by: Panattoni Development Company, Inc.
  • Constructed By: Clark Construction Group, LLC

Project Schedule

  • Phase 1: April - June 2022
    • Monday - Saturday, 6:00AM to 6:00 PM
  • Phase 2: July - August 2022

Questions?

If you have questions or concerns about this project, please contact Community and Economic Development at CED@arliingtonwa.gov or 360-403-3551.

Traffic Control Plans

Phase 1 - Traffic Control Plan

  • The first phase of construction will close the northbound and southbound legs of 43rd from 172nd. Detours and bypasses will be in place during this phase.
  • Eastbound and westbound traffic will travel directly through the intersection on two interior lanes, the light at 43rd will be temporarily covered.
  • Westbound traffic will be able to access Walmart, Heritage Bank, and the other businesses in that shopping area via the newly constructed 168th St.
  • Alternate access in and out of the 174th-179th Block neighborhood will be provided with a temporary road connecting 43rd to Airport Blvd.
  • In order to minimize impacts on traffic on 172nd, the contractor may require two to four nighttime full intersection closures.

Phase 2 - Traffic Control Phan

  • The second phase of construction will redirect eastbound and westbound traffic onto the completed outer lanes of the roundabout in order to construct the inner lanes and center island.
  • Access will be returned to the northbound and southbound legs of 43rd.  There will not be access for westbound traffic to turn left onto the south leg of 43rd
  • In order to minimize impacts on traffic on 172nd, the contractor may require two to four nighttime full intersection closures.
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11
  12. 12
  13. 13
  14. 14
  15. 15
  16. 16
  17. 17
  18. 18
  19. 19
  20. 20
  21. 21
  22. 22
  23. 23
  24. 24
  25. 25
  26. 26
  27. 27
  28. 28

Project Documents

Project Updates

  • March 30, 2022 - Estimated construction start date is April 4, 2022.
  • April 1, 2022 - The 43rd Ave Roundabout project will begin construction on Monday, April 4th. Construction will occur Monday thru Saturday from 6:00 AM to 6:00 PM. The contractor for the project, Clark Construction, will be diverting traffic around 43rd Ave during the first phase of construction. The detour will go into place Sunday evening at 6:00PM. 
  • April 8, 2022 - Next week construction will continue with the installation of the new stormwater system, site excavation and grading, and continued removal of the curb and sidewalks.  Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM.
  • April 15, 2022 - Next week scheduled work will include continued excavation, installation of electrical conduit and light pole bases, and the installation of crosswalk signs. Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM. 
  • April 22, 2022 -  Next week’s work includes continued electrical work, installation of fiber optic cable vaults, installation of a WSDOT camera pole, and placement of roadway base course.  Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM.
  • April 29, 2022 -  Next week’s work includes continued electrical work and addition of subgrade material, installation of fiber optic cable vaults, installation of a WSDOT camera pole, and installation of the north bio swale for the stormwater system. Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM. 
  • May 6, 2022 - Next week’s scheduled work includes the completion of the drainage system on the southwest corner, grading for curb and gutter, and begin to form and pour the curb and gutter. Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM. 
  • May 13 2022 - Next week’s scheduled work on the south side includes continued electrical and stormwater work. On the north side, work includes the installation of the bio swale, fiber vault, WSDOT camera system, and grade and pour for the sidewalk, ADA ramps, and splitter island. Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM. 
  • May 20, 2022 - Next week work will include continued concrete work on the sidewalk and ADA ramps and paving the first lift of asphalt on the north side of the roundabout. Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM. 
  • May 27, 2022 - Next week work will include installation of crosswalk bases and poles, and paving the first lift of asphalt on the south side. Construction is scheduled to occur Tuesday-Saturday from 6:00 AM to 6:00 PM. 
  • June 3, 2022 - Next week work will include concrete work on the north side and grading work on the south side. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. 
  • June 9, 2022 - Next week’s work will include PUD pole relocation, underground utilities, and grading & paving on the south side for the sidewalk, weather permitting. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM
  • June 17, 2022 - Next week’s scheduled work will include grading and paving on the north side of the roundabout and installation of ADA ramps on the south side. Construction is scheduled to occur Tuesday-Friday from 6:00 AM to 6:00 PM. 
  • June 24, 2022 - Next week’s scheduled work will include landscaping, and catch basin and curb installation on the north side. Traffic lanes will shift slightly to the south to accommodate for the work on the north side. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. 
  • June 28, 2022 - Reminder: Traffic will be shifting to the south at the intersection of 43rd Ave and 172nd St starting Tuesday, July 5th. 43rd Ave will still be closed at this intersection. Please continue to use detour routes in place for access to 43rd Ave and drive slowly through construction zones.
  • June 30, 2022 - Next week’s scheduled work will include demolition of sidewalk and ADA ramps on the north side, and installation of fiber vault and landscaping on the south side. Traffic lanes will shift slightly to the south to accommodate for the work on the north side. Construction is scheduled to occur Tuesday-Friday from 6:00 AM to 6:00 PM. 
  • July 15, 2022 -  Next week the contractor will move into phase 2 of the project. This phase will reopen 43rd Ave for right-in and right-out traffic only. Please see Phase 2 Detour Map above. Work will include the installation of additional light poles, and grading of the east and west splitter islands. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. 
  • July 22, 2022 - Next week work will include the installation of crosswalk bases, street lights, and SL electrical conduit. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. The Phase 2 Detour Map is available on the project website. 
  • July 29, 2022 - Next week work will include continued installation of crosswalk bases and streetlights, and installation of the splitter islands. Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM
  • August 12, 2022 - Next week work will include concrete work on the east/west bound splitter islands. Construction is scheduled to occur Monday-Saturday from 6:00 AM to 6:00 PM.  
  • August 19, 2022 - Next week work will include vehicle detection loop installation, crosswalk pole installation, paving at splitter islands and center island landscaping. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. 
  • August 26, 2022 - Next week work will include, paving at splitter islands and possible crosswalk pole installation pending inspection. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM.
  • September 2, 2022 - Next week work will include the final paving on the eastbound lane, the installation of temporary striping, crosswalk pole installation, and paving for the pedestrian pathway. Construction is scheduled to occur Tuesday-Friday from 6:00 AM to 6:00 PM. Paving will be completed during the night hours of 8:00 PM to 5:00 AM.
  • September 9, 2022 - Next week work will include crosswalk pole installation and center island landscaping. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. 
  • September 16, 2022 - Next week scheduled work will include the installation of crosswalk poles and a light pole. This work is dependent on material arrival. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. 
  • September 23, 2022 - Next week scheduled work will include the installation of a crosswalk signal pole, center island landscaping, the installation of fiber, final paving on east and west bound lanes, and installation of temporary striping. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. Paving will occur during the nighttime hours of 8:00 PM to 5:00 AM. 
  • September 30, 2022 - The roundabout is scheduled to be open by Monday, October 3rd in the morning.  Next week work will include center island landscaping. Construction is scheduled to occur Monday-Friday from 6:00 AM to 6:00 PM. Beginning on October 3rd, 168th St NE from 51st Ave to 43rd Ave will be closed to public access while the contractor performs final roadway improvements.  This work is estimated to be complete by October 22nd and the roadway is to reopen on Sunday, October 23rd.  Please use 172nd St to access 43rd Ave, the roundabout will be open by Monday, October 3rd in the morning prior to any closure of 168th St.