WSOR - Sauk City Bridge
Photos
Looking south
One pier and span has been removed, leaving a gap between the pony truss in the river and the swing span in the foreground.
Photo taken by Robert Thompson in October 2010
BH Photo #184169
Description
This railroad bridge, being on the Fox-Wisconsin waterway, was required by law to allow the passage of vessels. As such, it was built as a swing bridge. It was unlikely, however, to open often.On reviewing the photographs, I realized this is a very unusual swing bridge. There is no ring gear on the center pier, and at the shore end of the bridge, there is a ship's capstan and fairlead pulleys! It appears that to save money, this bridge was designed to be winched open and shut using chains or cables, as opposed to the conventional geared drive.
This is a non-symmetrical swing bridge; there is a counterweight on the shore end to compensate for the difference in span length.
(On edit, from the book "Movable Bridge Engineering":)
"There are some examples of bobtail or asymmetrical swing bridges, trussed type and girder type, from the early twentieth Century, but they seem to be concentrated in the upper Midwest. The Chicago, Milwaukee & St. Paul Railroad was a particularly vigorous proponent of this type of bridge... and at rural locations, such as the Wisconsin River. Most of these bridges are still in use for railway traffic, but some swing bridges in rural areas no longer open for navigation. ...but some examples, such as the one over the Wisconsin River at Sauk City, Wisconsin, is combined with several truss-type approach spans. The necessity of adding an expensive... counterweight to balance this bridge, when a symmetrical second arm could easily been added and the approach spans shortened, seems incongruous. It appears that the bridge was rope-operated from shore, so that the short shoreward span provided some advantage in the shorter length of operating rope required and a better angle of incidence of the tensioned rope at the span."
The swing span of the bridge was originally constructed in 1901 by American Bridge Company (Lassig Branch). In 1908, the through girder spans were placed along with a 216' secondhand Whipple Through Truss. In 1943, the Whipple Truss was replaced with a pair of secondhand pony trusses, a 112' Span built 1899 at Oxford Junction, Iowa and a 96' Span built at an unknown location.
Facts
- Overview
- Abandoned pony truss bridge over Wisconsin River on Wisconsin & Southern Railroad
- Location
- Prairie du Sac, Sauk County, Wisconsin, and Dane County, Wisconsin
- Status
- Abandoned
- History
- Built 1901 and 1908, Rebuilt 1943; Demolished 2002 and to be Demolished 2018
- Builders
- - American Bridge Co. of New York (Lassig Brach)
- Lassig Bridge & Iron Works of Chicago, Illinois
- Railroads
- - Chicago, Milwaukee, St. Paul & Pacific Railroad (MILW)
- Wisconsin & Calumet Railroad (WICT)
- Wisconsin & Southern Railroad (WSOR)
- Design
- Pratt pony truss
Bobtail swing deck plate girder
Pony plate girder - Dimensions
-
Length of largest span: 120.0 ft.
Total length: 455.0 ft.
- Also called
- WICT - Sauk City Bridge
MILW - Sauk City Bridge - Approximate latitude, longitude
- +43.26489, -89.72699 (decimal degrees)
43°15'54" N, 89°43'37" W (degrees°minutes'seconds") - Approximate UTM coordinates
- 16/278679/4793842 (zone/easting/northing)
- Quadrangle map:
- Sauk City
- Inventory number
- BH 46753 (Bridgehunter.com ID)
Update Log
- April 10, 2018: New photos from John Marvig
- February 27, 2018: New photos from Robert Thompson
- July 30, 2017: Updated by Alexander D. Mitchell IV: Local officials proceeding with plans to remove three remaining spans
- July 3, 2017: New photo from Dana and Kay Klein
- February 24, 2017: New photos from John Marvig
- October 25, 2016: Updated by Alexander D. Mitchell IV: Bridge pier sank further Oct. 2016; link to article posted
- September 23, 2016: New Street View added by Dana and Kay Klein
- October 16, 2015: New Street View added by Brandon Cooper
- June 17, 2014: New Street View added by Luke Harden
- June 17, 2014: Updated by John Marvig: Added information, noted bridge is in Sauk City, not Prairie du Sac, and WSOR were the last operators and current owners of the bridge
- March 23, 2014: Updated by John Marvig: Added Build Date
- August 22, 2013: New photo from Douglas Butler
- October 21, 2012: Updated by Luke Harden: Added "vintage" image
- January 12, 2011: New photos from Eric Hanson
- December 24, 2010: New Street View added by Daniel Hopkins
- December 24, 2010: Updated by Robert Thompson: New information
- October 31, 2010: Added by Robert Thompson
Related Bridges
- MILW - Sauk City Bridge (Old) (Predecessor)
- MILW - Oxford Junction Bridge (Parts reused from)
Sources
- Robert Thompson
- Daniel Hopkins - chimera [at] clovermail [dot] net
- Eric Hanson
- Luke
- Douglas Butler
- John Marvig - marvigj27 [at] gmail [dot] com
- Brandon Cooper
- Dana and Kay Klein
- Alexander D. Mitchell IV
- Future of defunct Sauk City rail bridge in question | Regional news | wiscnews.com - A portion of the defunct Sauk City railroad bridge that spans the Wisconsin River has shifted and resettled due to high waters from September flooding. The bridge is part of
- 20180405_railbridgesauk prairie_wiscnews.com.pdf - Info
Comments
I've been getting pics almost daily of the work crews dismantling the bridge. Here's one of them bringing the truss span over to the work area by barge. It was then rolled off on dollies and cut up and hauled away.
The three spans that are collapsing will be removed in early 2018. However, the swing span will remain in place.
Information from the Milwaukee Road Archives at the Milwaukee Central Library provided some information on this unique structure. The two pony truss spans were relocated from other locations. The 112' span demolished in 2002 was originally located in Oxford Junction, Iowa and built in 1899; while the 96' Span was originally located somewhere else.
Got it. Thanks as always
Dana, the image you posted belongs on https://bridgehunter.com/wi/sauk/bryant-street/
This isn't good--it sure looks like the concrete pier supporting the truss is sinking. The entire span will be in the river before long.
The good news is the bridge is to become part of a new trail:
http://www.wiscnews.com/saukprairieeagle/news/local/article_...
This is better news for the back channel bridge, which is an older and more significant structure. I don't know if it is too late for this bridge (specifically the remaining truss) to be saved.
While boating on the river, I noticed a lot of distortion in the alignment of a remaining section of the bridge. I did not get any pics from the water but stopped on my way through Sauk City to a couple from shore.
Looks mother nature is tearing the bridge down, right now the truss piece and piece south of it are no longer in line with each other.
The missing span and pier was blown up several years ago, I cannot recall the exact year. The reason this was done was that the piers of the truss bridges are shifting in the riverbed, throwing the spans out of alignment.
>>Wow, it's hard to believe that the True Value store can leave that riding lawn mower right by the road without it getting stolen. Also, I'm surprised that the railroad track doesn't have a stop bumper there before the tracks cross the road.<<
1.Small-town Wisconsin. There's an old saying here; in a small town nobody uses their turn signals because everyone knows where you're going anyway.
2.Good observation. But since the line is partially dismantled on this side of the river, with no rolling stock or other access to outside trackage, they must have decided it wasn't a problem.
Wow, it's hard to believe that the True Value store can leave that riding lawn mower right by the road without it getting stolen. Also, I'm surprised that the railroad track doesn't have a stop bumper there before the tracks cross the road. I once saw a crew assembling a train and they lost track of the car count, and they drove the end car right through a warehouse roll-up door and drove the rail cars inside the building back through the back wall.
Thanks for the Street View, Daniel.
This page's URL is http://bridgehunter.com/wi/sauk/bh46753/
Unfortunate that they will not be reusing the truss..just one more span to bring in a new trail span for.