Wow!!! I was highly suspect, and I fully expected this to be confirmed. However, this is very significant on both a state level and a national level.
Thank you so much Troy for helping uncover one of the most significant bridges in Iowa. My goal is to find which spans of La Crosse this came from. There were four different bridges (Main Channel, East Channel, French Slough and Black River).
I do wonder what the story is here. Was it railroad and then a local road and then in the DNR land? Was it sold after La Crosse was replaced? I am planning on working towards answering these questions.
I made it back to the bridge today and did a bit more looking on the outside of one of the sides of the portal it has Trenton NJ and on the vertical members had the inscription Pat July 1874. I took some pictures but they did not come out the best due to the condition of the members. I tried to bring the inscription out as best I could with some snow.
I will try to swing over there again soon and see if I can find the inscription and post some additional photos. I need to hit that area anyway to get additional pictures for my facebook page Bridging the Driftless. This site has been an incredible resource for me in my research for that page so anything I can do to help is a small thank you for all the work that has been put into it.
I had to stare at this one for a bit..I knew I had seen something similar before, but when I saw the almost perfect match in design, that was pretty cool. Looks like I'm gonna have to get back up to Allamakee County.
It's unfortunate that the Milwaukee Road Archives are no longer staffed. I would say its almost certain this bridge came from one of the many 1870s La Crosse spans, but I would love to know which channel it originally crossed. Being fabricated in 1876, the only railroad trusses I know in Iowa are older are both in Dubuque..
Good work finding that connection John, my first thought when I saw that portal bracing is it looked like something I had seen on an ancient railroad bridge but I couldn't remember where! This is a highly significant span!
Troy,
Thank you so much for posting these pictures. To me, this very much looks like a railroad bridge that was reused. I was poking around a little bit, trying to see if I could find a similar span that would've been on the Chicago, Milwaukee, St. Paul & Pacific Railroad system. The Milwaukee Road had a branch which went right next to this bridge. Some bridges closer to Waterville appear to have been upgraded in the 1930s or 1940s, which aligns with when this bridge first shows up in aerial imagery in 1952.
I did manage to find a bridge with very similar details, located in Eau Claire, Wisconsin (http://bridgehunter.com/wi/eau-claire/bh47520/). The eastern two spans of that bridge were originally built in 1876, before being shortened from 160' and moved to the current location. That bridge was strengthened in 1941, but many of the original details are still evident. Judging by the photos posted, it appears the following details are identical:
-Portal and sway bracing is set on top of the truss, indicating a replacement of the original portals
-the endpost has a bevel in it where it meets the top chord
-the pinned connections rest on top of the floor beam
-the heel bracing on the sway bracing is virtually identical
-the vertical members are virtually identical
-all pin connections appear virtually identical
I believe confirmation that this span was originally built as a railroad span in 1876, before being moved to a branch line and eventually to road use could be had by finding this inscription on the vertical members: http://bridgehunter.com/photos/35/31/353162-L.jpg
While I have no way to confirm yet what the history of this bridge is, it does seem very likely that this span is related to the Eau Claire span.
I am glad to be of help on this. Here are some more pictures. I wish the light had been better but sometimes we take what we get. The turn at the south end of the span would have been fairly tight due to the hillside when it was in use.