8 votes

Mosquito Lake Road Bridge


Photo taken by Jeffrey N. Curtis.

License: Creative Commons Attribution-Share-Alike (CC BY-SA)

View this photo on Flickr

BH Photo #236908


Street View 


This bridge was built in 1915 by the Toledo Bridge and Crane Company and the Weymouth Construction Company. It was originally located across the Nooksack River on Old Guide Road, West of current WA 539, south of Lynden. In 1951 the steel through-truss was moved to its present location across the Middle Fork Nooksack River, when a modern structure replaced it on a new alignment on Guide Meridian Road. When relocated two truss panels where removed, reducing the 380-foot bridge span to its present 338 feet. Nonetheless, the bridge remains the longest pin-connected highway bridge in Washington State. In 2007 Whatcom County replaced the deck and approaches and painted the bridge.

Source: Spanning Washington Craig Holstine and Richard Hobbs Lynden Pioneer Museum - Richard McDonald


Through truss bridge over Middle Fork Nooksack River on Mosquito Lake Road
Whatcom County, Washington
Open to traffic
Built 1915; Moved here and modified 1951; Rehabilitated in 2010
- Toledo Bridge & Crane Co. of Toledo, Ohio (Contractor)
- Weymouth Construction Co. (Contractor)
Pennsylvania through truss
Length of largest span: 337.9 ft.
Total length: 416.0 ft.
Deck width: 15.4 ft.
Vertical clearance above deck: 17.5 ft.
Posted to the National Register of Historic Places on July 16, 1982
Also called
Middle Fork Nooksack River Bridge
Approximate latitude, longitude
+48.78543, -122.11283   (decimal degrees)
48°47'08" N, 122°06'46" W   (degrees°minutes'seconds")
Approximate UTM coordinates
10/565167/5403983 (zone/easting/northing)
Quadrangle map:
Canyon Lake
Average daily traffic (as of 2018)
Inventory numbers
NRHP 82004305 (National Register of Historic Places reference number)
BH 34606 (Bridgehunter.com ID)
Inspection report (as of August 2018)
Overall condition: Fair
Superstructure condition rating: Satisfactory (6 out of 9)
Substructure condition rating: Good (7 out of 9)
Deck condition rating: Very Good (8 out of 9)
Sufficiency rating: 66.8 (out of 100)
View more at BridgeReports.com

Update Log 

  • January 16, 2017: New photo from Luke
  • January 16, 2017: Updated by Christopher Finigan: Added category "Pin-connected"
  • January 16, 2017: New Street View added by Dana and Kay Klein
  • December 15, 2014: Photo imported by Dave King
  • July 4, 2014: Updated by Luke Harden: Pin was several feet from the actual bridge, bridge still exists. Added info about 2010 rehab
  • August 7, 2012: Photo imported by Luke Harden
  • March 18, 2012: Updated by Craig Philpott: corrected location



Mosquito Lake Road Bridge
Posted January 16, 2017, by Mandy (gagnon [at] whatcom [dot] org)

went across it today....still a beauty.

Mosquito Lake Road Bridge
Posted February 16, 2016, by Nathan Holth (webmaster [at] historicbridges [dot] org)

Out of the corner of my eye I saw what looked like a pin-connected Pratt thru truss featured on an "Agent Carter" ad/trailer on ABC tonight. While trying (without success) to locate this ad/trailer online so I could get a better look at the bridge and maybe identify it, I was bombarded with a Mercedes advertisement... which featured ANOTHER bridge... THIS bridge!

Mosquito Lake Road Bridge
Posted December 11, 2010, by Anthony Dillon (spansaver [at] hotmail [dot] com)

This is a beauty indeed!

In reading the history, I am a little surprised that they reduced it's length by removing 2 panels.....and then added approach spans to it.

Mosquito Lake Road Bridge
Posted December 11, 2010, by Tom Hoffman (tehoffm [at] hotmail [dot] com)

Nice Pennsylvania Truss!