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|
[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|
|Karen 'Cab' Mathis shared|
Dave Mathis took a great picture!
|Sean C. Clancy posted|
|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.
|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
Bridge Hunter comments:
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.
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.
They didn't have 18-wheelers with 53' trailers back in 1931.
Closed due to concerns about the effects of high water on the bottomland road on Wisconsin side. [Flood of 2019]
Blackhawk bridge has reopened after being closed due to road washout(leading to a fatal accident) on the Wisconsin side.
|Dedecation Booklet via Historic Bridges, p20|
|Dedecation Booklet via Historic Bridges, p29|
|IaDOT via WaukonStandard, 2017|
|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.]
|2004 Feasibility Study, p2-7|
|2004 Feasibility Study, p2-14|
|safe_image for Best Times to be on Main Street in Downtown Lansing|