Looks like I need to correct my previous comment about these triple-intersectionals being more common than quadruple intersectionals. I assumed they were more common based on the fact that they are dominant in Kansas. They appear to be extremely rare elsewhere, however.
It appears that this span and the Smoky Hill River Bridge in Kansas share very similar portal features and possibly even the same builder.
Interesting discussion on the differing Triple and Quadruple Lattice trusses. My knowledge of them here in Indiana is somewhat limited. We do have an abandoned dual-track Quadruple in Pulaski County:
But I am much more familiar with the Fredricksburg Bridge:
This may be the only surviving example of a non-railway built Triple-intersection Lattice. After being closed for many years on a county road, this bridge is scheduled to be moved to a park for trail use. It's survival and restoration will be a nice complement to the only Triple-intersection Pratt known to survive:
Thanks for the clarification, Robert. As it turns out, I have seen the bridges that your links reference, but I've not noticed that they were triple-intersection Warrens--I think that I just saw the lattice configuration and assumed quadrangular, since those are most common in Minnesota and Wisconsin. Somehow, this bridge really stands out (maybe the silver paint!), and perhaps that's how I noticed it.
Interesting comment. The Quadrangular Lattice trusses seem to be dominant in the upper Midwest, but the Triple-Intersection Lattice trusses are the most common form of Lattice truss in other areas.
In Kansas, where the triple-intersectional trusses dominate, most of them appear to have been used by the Union Pacific Railroad, which also appears to have used this Idaho example.
The main variation I see with Triple-Intersectional Lattice trusses in Kansas is the portal bracing. Arched lattice bracing with Town Lacing is found on at least two Lattice truss bridges:
Other Triple-Intersectional Lattice trusses feature a less decorative bracing with V-lacing:
Ah this bridge. I always seemed to be passing through with daylight fading or the dead of night on the way to Missoula. Would have liked to stop and photograph one of those days.
Wow! This bridge is incredible! I have seen plenty of double-intersection and quadrangular (quadruple intersection) Warren trusses, but this is the first triple-intersection Warren that I have ever seen! It is great to see that this beautiful structure was preserved and converted for trail use for the general public to enjoy!