Purdon Crossing Bridge
Description
This is the only bridge of its kind still in use in the state of California and is HAER documented.Facts
- Overview
- Pratt half through through truss bridge over South Yuba River on Purdon Road
- Location
- Nevada County, California
- Status
- Open to traffic
- History
- Built 1889, rehabilitated 2013
- Builder
- - Cotton Brothers of Oakland, California
- Design
- Pratt half-height through truss with road deck carried half way between top and bottom chord.
- Dimensions
-
Length of largest span: 145.0 ft.
Total length: 191.9 ft.
Deck width: 11.2 ft.
Vertical clearance above deck: 14.7 ft.
- Recognition
- Posted to the National Register of Historic Places
- Also called
- Purdon Road Bridge
- Approximate latitude, longitude
- +39.32771, -121.04651 (decimal degrees)
39°19'40" N, 121°02'47" W (degrees°minutes'seconds") - Approximate UTM coordinates
- 10/668379/4354963 (zone/easting/northing)
- Quadrangle map:
- Nevada City
- Elevation
- 1695 ft. above sea level
- Average daily traffic (as of 2018)
- 71
- Inventory numbers
- CA 17C-24 (California bridge number)
BH 11226 (Bridgehunter.com ID) - Inspection report (as of August 2018)
- Overall condition: Poor
Superstructure condition rating: Fair (5 out of 9)
Substructure condition rating: Poor (4 out of 9)
Deck condition rating: Fair (5 out of 9)
Sufficiency rating: 12.9 (out of 100)
View more at BridgeReports.com
Update Log
- June 7, 2019: Updated by Erik Hoffman: Added category "Lally columns"
- June 19, 2017: New Street View added by Dana and Kay Klein
- October 21, 2015: Updated by Erik Hoffman: Added category "Last of its kind"
- August 9, 2015: New Street View added by Erik Hoffman
- May 21, 2013: Updated by Nathan Holth: Bridge to be rehabilitated.
- November 12, 2010: Updated by Craig Philpott: added builder and photos
- May 11, 2010: Updated by Craig Philpott: added photos
- March 16, 2010: Updated by Craig Philpott: Updated design and added streetview
Sources
- Craig Philpott - craigphilpott63 [at] gmail [dot] com
- Nathan Holth
- Erik Hoffman - norcalroadswebsite [at] gmail [dot] com
- Dana and Kay Klein
Comments
Swung by the Purdon again the other day because I’d heard it was scheduled to be closed for the coming month to allow for repairs.
I was both curious about what was in need of repair and to learn a little about the resume of whatever entity was chosen and contracted to execute them.
Though it was a few days into the scheduled closure no one had yet mobilized.
Just curious, what makes this last of it's kind? Pinned half through?
It is a relief to hear that one of the most significant and unique historic bridges in California remains after the floods!
That is great news. Thanks for the update. We were concerned about this one.
I drove across the bridge twice yesterday while running a bird survey route. Yes, it is still standing even after our very rainy winter.
Does anyone know if this bridge made it through the January 2017 flood?
To quote from: "Historic Highway Bridges of California" 1990, California Dept. of Transportation: "The Purdon Bridge is the only known example in California of a half-through truss, an unusual truss form in which the deck is carried approximately half-height between the top and bottom chords... The bridge was designed and built by Cotton Bros. and Company.
Very unique! Have never heard of a "half" through truss
The bridge is open and can be crossed by vehicle. It is a single lane bridge.
This page's URL is http://bridgehunter.com/ca/nevada/17C0024/
If the last inspection was accurate, then hopefully they're working on the substructure.
A very unique span to say the least!