I know nothing about this structure, I believe when I first added this bridge it was listed with an unknown build date. Then Charles posted something about the 1908 build date which was incorporated into the listing.
I would agree that the truss details are more consistent with something pre-1900. My guess is that the truss was moved to this location in 1908 from somewhere else in the country.
Most rail trusses in the northwest prior to 1900 were timber trusses built in the 1880's and 90's. My guess is the timber decayed away in 20 to 30 years and recycled trusses were brought in to replace the timber. There are plenty of examples of this practice around Oregon.
I agree that the portals and the pin connections indicate an older bridge, however I haven’t seen a subdivided Warren that’s pin connected before this. I would think if it was an 1880s bridge, it probably would’ve been built as a whipple. Perhaps this one was built in the 1890s and moved here? Relocation was quite common on railroads, especially former main line spans that had life left in them.
Does anyone else think that this bridge's pin-connected trusses and their subdivided, modified Warren truss are a little elaborate for a 1908 bridge? I'm wondering if this is a bridge relocated here in 1908. Cannot find any info online. I don't recall ever seeing a pin-connected Warren truss of any variety on a railroad that wasn't pre-1900. Most are 1880s.
I have fixed the mix-up with the railroad that built the bridge.
This page specifies the bridge was built in 1908 by Southern Pacific Railroad. This cannot be correct as this railroad line has never been owned by Southern Pacific. This railroad line was built by the Oregon Electric Railroad, which competed with Southern Pacific for the movement of passengers and freight between Eugene, Oregon and Portland, Oregon. The Oregon Electric ceased passenger services circa 1933, and was later acquired by the Seattle, Portland & Spokane RR, which was acquired by Burlington Northern RR. BNSF still owns the line today, and has leased it to PNWR since circa 2000.
"A contract will be awarded to cover the replacing of timber structures with steel spans across the Calapooia river, on the Oregon Electric, at Albany, Ore., at an estimated cost of $90,000. The filling of a timber bridge and placing a reinforced ..."
Excerpted from https://books.google.com/books?id=EY0lAAAAMAAJ&q=Oregon%20el...
and
https://hh-today.com/work-upgrades-trestle-on-pw-line/?fbcli...
Says a G&W/PNWR PR guy sais it's late 1800s, but a commentor says there's a 1908 cutout on the upper part of the bridge.