Industrial History: 1931 WI-82 Black Hawk Bridge over Mississippi River at Lansing, IA

(Bridge Hunter; Historic Bridges; John A. Weeks III; HAER: Facebook Group; see below for satellite)

It doesn't take any bridge expertise to spot the suspended span is in this cantilever bridge!

Photo from HAER IOWA,3-LANS,1--4 from ia0419

Satellite
[I saved the image because of the construction barges. I learned that in 2013 they added dolphins (pier protection bumpers) and repainted the bridge. But Iowa DOT is working on replacing it. Or just removing it because the traffic density is so low.]

Then, as now, the bridge consisted of a three-span cantilevered through truss of approximately 1,127', comprised of two cantilevered units of about 415' and one suspended span of about 297'. Each cantilevered unit consists of an anchor arm of about 237' with a cantilever of about 178'. The two cantilevers and the suspended span provide a channel crossing of about 653'. The cantilevered units are carried by concrete piers supported by foundation piles. The bridge was originally about 25' wide with an approximately 22' roadway. [HAER, pp3-4

John Weeks III

Iowa Road Trip posted
A view of the Black Hawk Bridge from Mt Hosmer in Lansing, Iowa

Karen 'Cab' Mathis shared
Dave Mathis took a great picture!

Sean C. Clancy posted

Jared S Kiley posted
BlackHawk Bridge just before sunrise this morning in Lansing.

Michael Coyle posted
Lansing and the Blackhawk Bridge

Allyson Crotty posted
Black Hawk Bridge - Lansing, IA. Shot in night mode on iPhone 11 Pro, edited to black and white with Snapseed.

Gabby Hayes commented on Allyson's post, cropped
Snapseed is a great app. This is the Bayview Bridge in Quincy, Illinois, taken with a Galaxy phone and processed with Snapseed.

Gavin Garcia posted
Black Hawk Bridge Lansing, Iowa

John Rethwisch posted
CP Railroad #8710, southbound along the Mississippi at Lansing, Iowa on a sunshine filled October afternoon.

Betsy Stahl posted
Black Hawk Bridge, Lansing

Craig Chumbley posted
Mount Hosmer Park in Lansing has to have the one of best views of any city park in the Midwest. Looking downstream at the Mississippi River with the Blackhawk Bridge in the foreground.

This is obviously a popular vantage point.

Linda Tauke posted

Cheryl Tobin Kiernam commented on Linda's post

Comments on Linda's post

Bridge Hunter comments:

Black Hawk Bridge

Posted April 27, 2019, by Don

Closed due to concerns about the effects of high water on the bottomland road on Wisconsin side. [Flood of 2019]

Black Hawk Bridge

Posted June 2, 2017, by Don Morrison

Blackhawk bridge has reopened after being closed due to road washout(leading to a fatal accident) on the Wisconsin side.
http://www.kcrg.com/content/news/Highway-82-closed-between-I...

Dedecation Booklet via Historic Bridges, p20

Many times the suspended span is built on barges then floated under the bridge and lifted into place. Evidently, if the cantilever leaves are strong enough to hold a live load, they are strong enough to hold an additional dead load during construction.

Dedecation Booklet via Historic Bridges, p29

Steel is strong enough in tension that just a couple of tie bars can hold one end of the suspended span.

One of four photos posted by Pat Lane
American Princess going under Blackhawk Bridge in Lansing, Iowa @1PM today!!! Thanks evil eye Talene Harmon Eddelson, we almost missed it!!
Madison Berry: That’s not American princess it’s American Duchess

Iowa DOT is studying how to replace the bridge. This is actually good news because some comments indicated that they were seriously considering tearing down the old bridge and not replacing it. I wonder if they would run a ferry or if they would require people to travel to either La Crosse or Prairie du Chien. Both are 40 miles away.

IaDOT via WaukonStandard, 2017

When asked if the current bridge could be kept for pedestrians and bicyclists if a new one was built, a DOT official responded that the DOT is not in the business of maintaining unused bridges. If the bridge was to be kept, it would need to be purchased by a group or an individual who would maintain it as a private enterprise.
[Reporter Susan Cantine-Maxson via WaukonStandard]

2004 Feasibility Study, p2-15
[This shows why the Coast Guard has told the railroads to replace their swing bridges with lift or high-level bridges.]

They didn't have 18-wheelers with 53' trailers back in 1931.

2004 Feasibility Study, p2-7

2004 Feasibility Study, p2-14

Iowa Road Trip posted
Black Hawk Bridge in Lansing, Iowa.
Anthony Clark: It is literally one of a kind. Amongst the rarest and most historically significant bridges in existence. Multiple elements each make it rare and unique on their own - combined, the uniqueness is off the charts. At first, it appears to be a continouos cantilever truss. It is actually three separate spans. Two cantilever trusses with a center Pennsylvania truss. The center Pennsylvania truss is not connected to the cantilever spans at the top. It is only connected via the road deck at the bottom. It is just hanging in the air. The long approach span on the Wisconsin side appears to be a simple viaduct. It is not. It is a six span Pratt through truss with the road deck on top of the trusses rather than passing through them. Multi-span Pratt through trusses have become increasingly rare. There is one five span and one four span remaining in Iowa. A six span is unheard of. So, the Wisconsin approach alone is unbelievably rare. Add that to the one-of-a-kind main span and this bridge needs to be saved at any and all costs.
[Actually, a cantilever truss with a suspended span is the norm. It is just not as obvious as this one that the middle span is suspended.]

I looked for the 6-span approach viaduct on a satellite map, but I could not find it. There is a non-trivial bridge over a backwater, but it is not six spans. I saw shoulders on the approach except for some small bridges.