1 vote

I-5 - Stillaguamish River Bridge (SB)


Stillaguamish Bridges

Washington State Department of Transportation

License: Creative Commons Attribution-NonCommercial-NoDerivs (CC BY-NC-ND)

View this photo on Flickr

BH Photo #315579

Street View 


The southbound I-5 Stillaguamish River Bridge was built in 1933. It originally carried two lanes in each direction of US 99. When I-5 was built in the 1960s, the bridge became part of the freeway. In 1971, a new bridge was built just east of the original one to carry three lanes of northbound I-5. The old bridge continued to handle three lanes of southbound I-5. The bridge deck was replaced in 2014. The bridge also got repainted and some rivets and joints replaced in some areas to preserve the bridge in 2021.



Through truss bridge over Stillaguamish River on I-5
Snohomish County, Washington
Open to traffic
Built 1933, bridge deck replaced 2014
Parker through truss
Length of largest span: 200.1 ft.
Total length: 859.0 ft.
Deck width: 47.9 ft.
Vertical clearance above deck: 16.4 ft.
Approximate latitude, longitude
+48.19667, -122.21000   (decimal degrees)
48°11'48" N, 122°12'36" W   (degrees°minutes'seconds")
Approximate UTM coordinates
10/558705/5338461 (zone/easting/northing)
Quadrangle map:
Arlington West
Average daily traffic (as of 2016)
Inventory number
BH 34537 (Bridgehunter.com ID)
Inspection report (as of March 2018)
Overall condition: Fair
Superstructure condition rating: Satisfactory (6 out of 9)
Substructure condition rating: Satisfactory (6 out of 9)
Deck condition rating: Very Good (8 out of 9)
Sufficiency rating: 64.8 (out of 100)
View more at BridgeReports.com

Update Log 

  • November 23, 2022: New photo from Richard McDonald
  • June 16, 2016: Updated by Evin Fairchild: bridge deck replaced in 2014
  • February 10, 2015: Photos imported by Dave King
  • March 19, 2012: New Street View added by Michael Goff


  • K. A. Erickson
  • Mike Goff - michael [dot] goff [at] hotmail [dot] com
  • Richard McDonald


I-5 - Stillaguamish River Bridge (Southbound)
Posted June 16, 2012, by Daryl Mills (greimatter [at] comcast [dot] net)

This bridge was originally built for US99 and was first used as a two lane bridge. It was built wide enough for four lanes and when the US99 expressway was built through this area in the 50's it carried two lanes in each direction. It now serves as the three Southbound lanes of Interstate 5.