7 votes

Gualala Road Bridge


Gualala Rd Bridge

Looking W

Photo taken by Craig Philpott in September 2009


BH Photo #146319

Street View 

A Group History 

Written by John C Stutz

This span is a ~130’ through Pratt mainline railroad bridge of circa 1880, one of at least six that were recycled to minor rail lines in Sonoma and Marin Counties circa 1905-10. A CalTrans bridge report for one of these mentions drawings with the initials “G, H & S A”, suggesting the Galveston, Harrisburg & San Antonio railroad, the Southern Pacific’s subsidiary in Texas. I believe these bridges represent original spans from the SP’s Sunset Route, dating from 1877-83. Similar spans were cascaded down to many of the SP’s branch lines on the West Coast, and to associated private lines like the Diamond & Caldor, in the same time frame, all part of SP’s Harriman era upgrading.

Of these six, one was sold to the Gualala lumber mill and erected on steel cylinder piers at their logging railroad’s crossing of the North fork of the Gualala river. As of 2018 it still stands on those piers, albeit raised about 6’ to clear floods, on the Gualala 501 Rd. On the Northwestern Pacific’s narrow gauge line along Tomales Bay to Duncan Mills and Cazadero, two spans replaced the Howe Trusses at the mouth of Keys Creek in 1906. The steel cylinder piers remain, adjacent to highway 1, two miles south of Tomales. In 1930, as the narrow gauge was lifted, one was re-erectd over Lagunitas Creek and Sir Francis Drake Blvd., in what is now Samuel P. Taylor State Park. That one was long since replaced by a modern bridge for the Cross Marin trail. The remaining three were used on the NWP’s standard gauge Russian River branch, replacing the washed out second crossing of the Russian River near Northwood, above Monte Rio, in 1909. That branch was abandoned in 1935. Several of its bridges were recycled for highway use, the Northwood spans among them. Two were erected on the Stewart Point – Skaggs Spring Road, at the Gualala River and Haupt Creek crossings, and one on the Cloverdale – Geysers Road over Big Sulphur Creek. The Gualala R. span was replaced circa 1995, while the remaining pair are still visible in Google Satellite View as of 2018/03.

These are typical examples of Phoenix patent bridges built by Clark, Reeves & Co. of the Phoenix Bridge Works. The patented feature involves the columns (posts or compression members), wrought iron tubes assembled from segments riveted together along radial flanges. This makes an extremely efficient post, in terms of strength to weight ratio, but one lacking in facility for lateral connections to bracing elements. The Phoenix column was widely used in the 1870’s and 80’s, in both bridges and buildings, but had been superseded by 1900. For further information, see Thomas R. Winpenny’s history of the Phoenix Bridge Co., “Without Fitting, Filing, or Chipping”.


Pratt Through truss bridge over North Fork Gualala River on Gualala Road
Mendocino County, California
Open to traffic
Built in this location 1940
Pinned Pratt Through truss with Phoenix columns
Length of largest span: 129.9 ft.
Total length: 187.0 ft.
Deck width: 10.5 ft.
Vertical clearance above deck: 21.0 ft.
Eligible for the National Register of Historic Places
Approximate latitude, longitude
+38.77889, -123.50000   (decimal degrees)
38°46'44" N, 123°30'00" W   (degrees°minutes'seconds")
Approximate UTM coordinates
10/456569/4292358 (zone/easting/northing)
Quadrangle map:
Average daily traffic (as of 2011)
Inventory numbers
CA 10C-46 (California bridge number)
BH 11129 (Bridgehunter.com ID)
Inspection report (as of June 2017)
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: 27.1 (out of 100)
View more at BridgeReports.com

Update Log 

  • June 9, 2019: Updated by Erik Hoffman: Added category "Pier Bents"
  • March 6, 2018: Essay added by John C Stutz
  • October 4, 2013: New Street View added by J.P.
  • March 9, 2012: New photos from Craig Philpott
  • March 22, 2010: Updated by Craig Philpott: refined design description
  • March 1, 2010: Updated by Craig Philpott: Amended design
  • February 18, 2010: Updated by Craig Philpott: Corrected design
  • September 13, 2009: New photos from Craig Philpott

Related Bridges 



Gualala Road Bridge
Posted January 7, 2019, by Daniel

http://www.mendonomasightings.com/2013/04/25/the-green-bridg... states:

The travels of the North Fork Bridge are documented. It appears to have been initially shipped to Smith River, CA (about 30 miles north of Crescent City), where it served as a lumber mill railroad bridge. In 1909 it was moved to a lumber mill in Northwood, CA (between Monte Rio and Guerneville), and served as a railroad bridge spanning the Russian River. Finally, in 1941, it was moved to its current location on the Gualala River and converted to automobile use as a replacement for earlier bridges that had washed away.

that's a significantly different date for it's current location than I've otherwise seen, and it seems unlikely that one of three (nearly?) identical bridges in the region didn't come from the same place as the others, but I figured I'd post it anyway.

Gualala Road Bridge
Posted February 11, 2014, by John Charles Stutz

The Geysers Road, the Haupt Creek bridge, and the pre-1984 South Fork Guauala River bridge, are all typical 1870's era railroad bridges. Cal Trans documents mention drawings initialled GH&SA RR, suggesting the Southern Pacific's Texas subsidiary, and these spans are typical of those installed by the SP during initial construction of the Sunset and Oregon routes.

The 1909 build date quoted for the Geysers span, is actually when these spans were recycled to the NWP RR's Russian River branch, and installed above Monte Rio as a 3-span crossing. In the same time frame, similar spans were re-erected on the former NPCRR at Tomalas Estuary and Papermill Creek, and the Guauala RR's crossing of the North Fork. The later span still stands on the circa 1910 steel cylindrical piers, but was raised clear of the flood plain circa 1940.

Gualala Road Bridge
Posted December 7, 2009, by Dick Garland (GarWritz [at] aol [dot] com)

According to "Historic Highway Bridges of California", 1990 by Cal Department of Trans., the bridge was built in 1899. It is one of four remaining Phoenix Bridge Company bridges in California. No mention is made of the bridge being a relocation project (see page 167). See also pp 48 thru 53.

Gualala Road Bridge
Posted September 14, 2009, by Anthony Dillon (spansaver [at] hotmail [dot] com)

Definitely an 1870's-1880's span, and a beauty at that! Phoenix columns on the endposts, top chords, and main verticals. I also have heard of bridges from the East being replaced with newer spans and the old span dismantled and relocated far away. "Go West young man.....and take the bridge with you!".

Gualala Road Bridge
Posted September 14, 2009, by Michael Goff (michael [dot] goff [at] odot [dot] state [dot] or [dot] us)

This bridge is probably one of the many recycled truss bridges on the west coast. I have seen many old trusses that have been moved to the west coast from the Midwest that date from the mid to late 1800's, but have construction dates in the 1930’s and 1940’s.

As roads and railroads were improved in the more populous regions east of the Rocky Mountains, areas of the Pacific Coast were just developing there roadways. So, many structures were torn down and moved west.

Gualala Road Bridge
Posted September 14, 2009, by Robert Elder (robertelder1 [at] gmail [dot] com)

I will go out on a limb here and suggest that this brige was built well before 1940. I would suspect 1870s, given the columns and portal bracing. This bridge is definitely a great find!