The Mott Bridge over the North Umpqua River is located about 40 miles east of Roseburg off of OR-138. The 237-foot structure features a 135-foot three hinged braced spandrel timber arch main span, along with 50-foot approach timber trestles on each approach.
The rustic bridge carries traffic over the North Umpqua River on a 14.5-foot roadway and two 4-foot sidewalks. The bridge links OR-138 to the popular North Umpqua Trail as well as supplies access to the Forest Service and Oregon Department of Transportation maintenance yards on the opposite side to the river.
The timber bridge was built by the Civilian Conservation Corps in 1936, and is the last remaining three hinged timber arch of the three similar structures built in the Pacific Northwest during the Great Depression.
Dimensions
Length of largest span: 134.8 ft.
Total length: 236.9 ft.
Deck width: 14.4 ft.
Also called
North Umpqua River Bridge
Approximate latitude, longitude
+43.34287, -122.73489(decimal degrees) 43°20'34" N, 122°44'06" W (degrees°minutes'seconds")
Overall condition: Fair
Superstructure condition rating: Fair(5 out of 9)
Substructure condition rating: Fair(5 out of 9)
Deck condition rating: Good(7 out of 9)
Sufficiency rating: 62.3 (out of 100) View more at BridgeReports.com
Categories
Update Log
August 2, 2011: New photo from Michael Goff
March 21, 2011: New photos from Michael Goff
April 20, 2010: New Street View added by Michael Goff
June 19, 2008: Updated by Michael Goff
Related Bridges
Lone Rock Bridge (Downstream) - Two modern bridges between structures
From what I have found there are only three exposed timber truss vehicular structures remaining in Oregon.
Mott Bridge - http://www.bridgehunter.com/or/douglas/mott/
Middle Fork Willamette River Bridge - http://www.bridgehunter.com/or/lane/61805000001742/
Cascadia Park Bridge - http://www.bridgehunter.com/or/linn/17350016F04141/
I am always on the lookout for these rare timber structures, but like you said they are disappearing at an alarming rate.