2 votes

Mill Crossing Bridge


Photo taken by Craig Philpott


BH Photo #222443

Street View 


Although this bridge truss webs appears to be modular panels, is not a Bailey Truss. Once assembled, it follows the pattern of a warren with verticals. Each panel, however, is missing a diagonal.


Deck truss bridge over Lagunitas Creek on Mill Crossing
Marin County, California
Open to traffic
Built 1947
Steel Deck truss assembled from modular panels
Length of largest span: 71.0 ft.
Total length: 112.0 ft.
Deck width: 10.0 ft.
Approximate latitude, longitude
+38.02893, -122.74210   (decimal degrees)
38°01'44" N, 122°44'32" W   (degrees°minutes'seconds")
Approximate UTM coordinates
10/522633/4209055 (zone/easting/northing)
Quadrangle map:
San Geronimo
Average daily traffic (as of 1998)
Inventory numbers
CA 27P-2 (California bridge number)
BH 11085 (Bridgehunter.com ID)
Inspection report (as of July 2018)
Overall condition: Fair
Superstructure condition rating: Fair (5 out of 9)
Substructure condition rating: Good (7 out of 9)
Deck condition rating: Fair (5 out of 9)
Sufficiency rating: 32.4 (out of 100)
View more at BridgeReports.com

Update Log 

  • June 14, 2017: Updated by Fmiser: added category
  • June 12, 2017: Updated by Fmiser: removed "bailey" as truss design.
  • September 28, 2013: New photo from Craig Philpott
  • December 26, 2011: Updated by Craig Philpott: added photos, refined design.
  • June 6, 2010: New Street View added by Craig Philpott


  • Craig Philpott - craigphilpott63 [at] gmail [dot] com
  • Fmiser - fmiser [at] gmail [dot] com


Mill Crossing Bridge
Posted June 15, 2017, by Gil Graham (ggraham [at] baileybridge [dot] com)

"Bailey" became somewhat generic decades ago (like "kleenex" for tissue paper). I agree with the suggestions about using "modular panel truss" or "modular truss panel" as a description since there are several manufacturers, each with a variety of models or styles that look mostly the same.

FMiser's previous comments are also correct about the "Treadway" style. Like the "medium girder bridge" (MGB)it too was something related to the Military but not Bailey. I enjoy this website!

Mill Crossing Bridge
Posted June 13, 2017, by Fmiser (fmiser [at] gmail [dot] com)

Nathan, Gil may have to clarify - but I read it as a description of a general type, not a specific . Bailey seems to be only one of the US Army modular bridging trusses, usually not a deck truss though. A US Army deck truss that comes to mind is the MGB (Medium Girder Bridge). This bridge is not build with that truss either.

So my thought is rather than calling all of these modular panel bridges a "Bailey" - since ones such as this are not a Bailey truss at all - maybe there is a more accurate description.

"Modular", "pre-fabricated" and "panel" seem to be defining characteristics of this type, whether Bailey, Callender-Hamilton, Acrow, Mabey Johnson, Janson, Quadricon, or others. So maybe "pre-fab, modular steel panel truss"? Kinda wordy, but there are other wordy categories! All the examples I'm thinking of could clearly sorted.

Mill Crossing Bridge
Posted June 12, 2017, by Nathan B Holth (webmaster [at] historicbridges [dot] org)

Gil below commented on the exact type of bridge: US Army modular deck bridges. If there is concern about specificity of "modular" then the category could be called "US Army modular" for example may be better. Other countries have their own modular designs. Callender-Hamilton truss for example is another.

Mill Crossing Bridge
Posted June 12, 2017, by Robert Elder (robertelder1 [at] gmail [dot] com)


That seems reasonable to me. I am glad that you are still lurking in here. I was wondering where you had been.

Mill Crossing Bridge
Posted June 12, 2017, by Fmiser (fmiser [at] gmail [dot] com)

I changed the design type to Warren. And I'm wondering if there should be a category "modular"?

Mill Crossing Bridge
Posted June 12, 2017, by Gil Graham (ggraham [at] baileybridge [dot] com)

Several of these have been improperly labeled as Baileys. The confusion arises from he fact that these are US Army modular deck bridges. I think the nomenclature is either H5 or H10 based on the truss panel size. I believe the design pre-dates the Bailey design. If I come across more info on these I'll forward it on.

Mill Crossing Bridge
Posted June 11, 2017, by Royce and Bobette Haley (roycehaley111 [at] yahoo [dot] com)

Are not Baileys usually squared at the ends, verticals not diagonals

Mill Crossing Bridge
Posted June 11, 2017, by Dave King (DKinghawkfan [at] hotmail [dot] com)

This is labeled as Bailey truss but looks like a Warren to me. Maybe the angle has my eyes seeing this wrong.