Thursday, January 31, 2019

MoW: Bridge Truss "Repair"

Gil Moser posted four photos with the comment: "Can't remember the bridge number, I think it was on the river sub. It stayed like picture four [just a bunch of chains] for at least three years."

I know the EJ&E had a river sub. But I'll bet there are a lot of other railroads in the USA that also had a river sub. Maybe Gil is being deliberately vague to protect people's jobs.
Josh Rawls Looks like fatigue failure to me. It broke at a stress point.
Tom Mason thats a lot to break.
Dan Thomas Weld not a good repair for this old steel. Better to have bolted plates and angles. A very old bridge based on the bottom chord link and pin design.
Don Murphy I agree with the bolted plates and angles. I was Bridge Inspector on River Sub for several years and later Structures Supervisor. There is no way that would have stayed that way for 3 years back then.
Robert Oxley that's good steel though. The old stuff. [He probably means that it had a lot of pure iron from a blast furnace rather than just melted scrap steel.] Probably been red lead painted many times..lol
Kev Chaloner Would seem to be a bad design. The left hand web plate was not run past the angle bracket making the right hand web plate carry most of the load and fail by fatigue. That joint has been flexing for quite some time. I would be checking all the other ones quick smart.

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4, cropped
This shows that a truss member designed to take a compression force is not always subjected to a compression force. This break was caused by a tension force. More specifically, the forces probably changed between compression and tension as a train rolled by causing metal fatigue. If it was always under compression, the gap would not hang open.




I don't like "talking heads" videos, so I find these hard to watch. But there is some interesting information in them. So I'll just park them at the end of these notes. When he starts talking about "the lesson learned," I consider that the end of the relevant information.

(new window)


(new window)   (source)





Wednesday, January 30, 2019

Des Moines Trail/Union Railway (Wabash+Milwuakee) Bridge over Raccoon River In Des Moines, IA


If you are here because of the UP/C&NW/CGW bridge, then you need to go there.

Street View, Jul 2023

Christopher Robert posted
Downtown Des Moines, Iowa then and now.
Ray McCollough: Thanks. I don’t realize that bridge had MILW heritage.
 
Christopher Robert commented on Ray's comment
It was the Des Moines Union Railway (DMU) Bridge.
The DMU was jointly owned by the Wabash and MILW.
It was also used by the CB&Q, M&StL and CGW.
The bridge is now a footbridge and is the only remaining DMU structure.

1956 Des Moines SW and SE Quads @ 24,000

Bob Dover posted
Directly opposite the main part of downtown Des Moines, Iowa, crossing the Des Moines River, is the Red Bridge. Constructed by the Des Moines Union Railway in 1891, the Red Bridge is a hybrid construction type that has been partially reconstructed a few times. The ends of the bridge are steel-plate girder construction, but the two spans in the middle of the river are the original steel through-truss spans. The bridge was abandoned in 1996, but it was rehabilitated and reopened as a pedestrian and bicycle-only bridge in 2004. The bridge is painted bright red and lined with a modern white railing. In the center of the bridge, between the two through-truss spans, a modern platform extending off both sides of the bridge has been added to the original structure. This modern platform is outfitted with benches and is designed to provide a relaxing park-like space in the middle of the river. The Red Bridge is lighted at night, both from the outside, and with lighting of the steel components from within the truss. Because the Red Bridge is a very bright shade of red, the interior lighting makes the bridge appear as if it glows from within at night.
You can find photos of several of the downtown Des Moines bridges on www.bridgespotting.com. There are also detailed profiles of the Red, Green, and Riverside Park Drive bridges provided in my book, Bridgespotting Part 2: A Guide to Even More Bridges that Connect People, Places, and Times.


Tuesday, January 29, 2019

C&O Bridge over Wabash River in Peru, IN

(Bridge Hunter, no Historic Bridges, Satellite)

See CW Junction Tower for an analysis of how the C&O ran through Peru.

Jason Jordan shared
On the C & O of Indiana at Peru, IN. crossing the Wabash River.
Rob Kunkle photo
Not one, not two, but three C&O steamers heading south across the C&O bridge east of the power plant. 1949
[]Note that the "smoke" is white instead of black. This once again demonstrates that smoke is black during railfan excursions because the fireman is deliberately putting on a show for the cameras. Or maybe they are burning the "smokeless coalfrom the New River Coal Field in Southern West Virginia that the C&O served.
I once read that the C&O was the "mountain railroad of Indiana" because its diagonal path across Indiana took it over every river watershed in the state. But, of course, now I can't find where I read that :-(. Maybe that is why it takes three steam locomotives to pull a freight.

Satellite
I include a satellite image because of the log jam. It demonstrates how large they can grow if the debris is not cleared from active bridges. This jam must have stayed intact for a while because vegetation is growing out of it. I wonder what the vegetation is using for soil.
Mike Snow posted
Chesapeake & Ohio No. 446 F-15 C&O train #17 at Peru Indiana February 16, 1946 Swartz-McCarter Collection Neg No. 3949 photo by M.D. McCarter

James Boudraux posted
Crossing the Wabash River...Peru,In...8/77...R.Richard Koenig
rrPictureArchives: 1980 Amtrak train

FallenFlags: Chessie Cat on an engine

UP/Milw (Omaha) Bridge #15 over Mississippi River at St. Paul, MN

(Bridge HunterHistoric Bridges; John A. Weeks IIIFlickr in the open position; 3D Satellite)

Technically, this is not yet another swing bridge. It's a bobtail bridge. That means it is not symmetric. That is, one side is longer than the other. All though the differences in the length of the sides of this bridge are pretty small. I might have missed that it was a bobtail bridge if it wasn't for the conspicuous counterweight at the end of the short side. This bridge is also noteworthy because we seldom have a set of photos that include the interior of the control house as well as the machinery room.

Richard A Jeffery posted eleven photos with the comment: "I found a few pictures I had taken of Bridge 15. Located on the Mississippi River in St Paul MN. Bridge is known as the Omaha Bridge to the RR crews. Bridge was built in 1915."

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If you look closely you can see the steam crane on a barge used during during construction
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In the bridge house

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The controls that cause the bridge to move

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Entrance to the mechanical room under the tracks.

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Notice the high water mark from 1965

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11

A video of the span swinging open as viewed from a boat




Monday, January 28, 2019

Amtrak/Penn 1910 Portal Bridge over Hackensack River in New Jersey

(Bridge Hunter; no Historic Bridges; 3D Satellite)

Replacement Bridge

Why yet another swing bridge? Because it appears that I, as a Federal taxpayer, am going to help pay $1.5b to replace this bridge. (I'd rather pay for efficient rail travel than more roads.) Or is the $1.5b for the complete access project including a new tunnel? Nope, $1.5b is just for the bridge! The entire "Gateway" project is $24b with $10b for the tunnel. [CrainsNewYork (payware)] The new bridge is higher so that it doesn't need a movable span. I assume that is why the replacement is such an expensive bridge.

(Update: on page 11 of the Sep 2020 Trains magazine there is a little News Brief that the FTA has advanced the project to the engineering phase with a promise for more than $750m of funding for the $1.8b project.)

Amtrak from ProgressiveRailroading

safe_image for Northeast Corridor Portal Bridge in N.J. will be replaced
[Construction could begin in Spring 2021. The $1.81b project could get $811m in federal funding.]

Street View

Amtrak continues to plan a replacement of the more than 110-year-old Portal North Bridge, a two-track, swing-span structure over the Hackensack River in Kearney and Secaucus, New Jersey. The bridge often malfunctions, causing transit delays on the busy Northeast Corridor.
“It’s about 23 feet above water and rotates to open for marine traffic. It has not worked properly more frequently than we’d like, and causes massive delays to trains,” said Amtrak spokesman Craig Schulz.
Amtrak plans to replace it with a new 50-foot, high-level, fixed-span bridge that can accommodate faster trip times and boost reliability. The $1.5 billion, six-span bridge will not open and close like a movable bridge, said Schulz.
The bridge replacement is part of Amtrak’s Gateway program, which involves a series of projects aimed at doubling rail capacity between New York and New Jersey, and improving resiliency. The new Portal North Bridge and a Hudson Tunnel project comprise the program’s first phase.
The new bridge will be built to the north of the existing structure, which eventually will be dismantled. The new bridge will feature 10 percent more capacity.
The project has a five-year construction schedule and the bridge has been designed, said Schulz.
Amtrak has collected half of project costs from local partners and applied to the Federal Transit Administration (FTA) for a core capital program grant. The railroad is awaiting the FTA’s review. For now, Amtrak has performed some early work for the project.
At some point, the railroad also expects to replace the Portal South Bridge with a comparable structure, said Schulz.
ProgressiveRailroading
I saved a satellite image since this bridge is supposed to be replaced.
3D Satellite
"Portal is considered one of the busiest railroad bridges in the western hemisphere, used by up to 200,000 passengers a day. When it gets stuck, it causes long lasting problems for passengers." Two problems closing it in one day delayed 80,000 passengers "on 16 Amtrak trains and 148 NJ Transit trains" because the second problem happened during rush hour. [www.nj.com]
 
William Billson posted
PRR / Amtrak Portal Bridge
James Kenney: William Billson Is that a dead man pedal on the floor?
William Billson: James Kenney I believe so.
Brian R. Wroblewski: Definitely an upgraded & updated panel if that's an older bridge.


Most of the closure problems are getting the miter rails to extend across the gaps and lock into position. "Sometime workers have to use sledge hammers to bang the miter rails between the bridge and land back into the locked position. On Nov. 23, 1996, an eastbound Amtrak train derailed on the Portal Bridge and sideswiped a westbound Amtrak train. The National Transportation Safety Board blamed the incident on the miter rails." [www.nj.com]

eBook, p32
.

New Portal Bridge


Railway Age  (source)
Artist’s rendering of Portal North Bridge, courtesy of Amtrak.

NJ Transit posted two images with the comment:
Replacing Portal Bridge will increase capacity and ensure reliability for the more than 450 NJ TRANSIT & Amtrak trains a day that cross it. We thank U.S. Department of Transportation, our partners at Federal Transit Administration & Federal Railroad Administration, and the NJ Congressional Delegation for their support of this shovel-ready project.
Vishal Parmar About damn time! That bridge should’ve been replaced during the 2000s or 2010s. I do hope the speeds will be faster and with the new bridge not having to open up for traffic I would hope you can arrive a lot faster in leaving or going into NYP.
Mike Jiran Thank Chris Christie.
Vishal Parmar Mike Jiran he killed the tunnel. ARC was a disaster. What CC was guilty of was killing the ARC, endorsing the Gateway Plan via lip service and walked away. He didn’t fight for funding nor endorsed it and didn’t kick in any financial love that it should’ve gotten much earlier on.
Christopher Stephans It needs to be at least four tracks wide. Any amount of tracks less than four will be a waste of time and money.
[Several comments reflect what was on my mind: does support mean it is FUNDED?]
Mike Lordi What is response to this? https://t.co/i821yNrngs?amp=1 "Since 2016, this Editorial Board has been the lonely voice criticizing Amtrak’s $30 billion Gateway boondoggle as the wrong solution to the real need to repair two waterlogged tunnels and double trans-Hudson passenger capacity....NJT is seeking a 'core capacity' grant. Under federal law, such a project must boost ridership 'by not less than 10 percent.' But a new Portal North Bridge never could increase capacity by even a single seat, as it is a two-track substitution for a two-track bridge, carrying the same 21 peak-hour morning trains into Penn Station....In submissions to the FTA starting in 2016, NJT said that a new bridge would allow for double-decker rail cars and also longer trains, which would add 11.6% more seats to those 21 trains. But 13 of the trains were already double-deckers, and a new bridge was irrelevant to making the other eight multi-level or lengthening trains."
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William Billson posted
PRR/Amtrak Portal bridge in Kearny NJ.


rtands
[It appears that Amtrak's original plan was to build new tunnels and then economically fix the old tunnels because trains could be diverted to the new tunnels. Now Amtrak needs to figure out how to fix tunnels while they handle over 450 trains a day. It is a shame that Trump is spending money on a wall instead of new tunnels.]

safe_image for Project to Repair Century-Old NJ Rail Bridge Gets $800 Million Boost From Feds
"Nearly 200,000 people and 450 trains cross the bridge each day during normal times....A study released last year found that passengers traveling between New Jersey and New York had experienced rail delays of five hours or more about 17 times per year in recent years. About three-quarters were attributable to problems with the tunnel and the rest were due to problems with the bridge."

A comment on a post: "Portal bridge is far beyond its replacement age. The planned replacement is well underway and the design is a massive elevated fixed structure over the Hackensack River."
 

safe_image for Issues at Portal Bridge to continue into weekend for NJ Transit, Amtrak
[Mother's Day weekend: May 13, 2023]
"Delays, but few cancellations, expected as work continues to address signal problems....A total of 11 outbound and two inbound NJ Transit trains were cancelled during [Friday's] afternoon rush hour and into this evening....An Amtrak spokesman said a contractor “caused an electrical issue affecting critical systems” at the site." The problems began Thursday.
 
AltoonaWorks posted
5/2024 - From a Philadelphia-bound Acela we got this shot of the new Portal Bridge under construction over the Hackensack River outside of NYC.  The current bridge opened in 1910 and hosts 450 trains per day as of 2015 according to Wiki.

The arches are fabricated in the Port of Coeymans and shipped down the Hudson River.
Sharron Crocker posted via Dennis DeBruler

2 of 3 photos posted by the Times Union with the comment:
The first section of the Portal North Bridge was towed out of the Port of Coeymans on Tuesday on its way to installation as part of a downstate commuter rail crossing over the Hackensack River.⁠⁠
The span is part of a new $1.7 billion bridge that will connect commuter trains from New York City to New Jersey.⁠⁠
The new span is the first of three sections of the bridge that are being built in the port by the Swedish-based Skanska construction company.⁠⁠
📸: Will Waldron / Times Union
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Mammoet posted three photos with the comment:
A few weeks ago, the first of three sections of the new Portal North Bridge began its journey down the Hudson River, heading to its final placement over the Hackensack River.
Using their expertise in heavy lifting, Mammoet's team successfully transported the massive bridge section - over 120 meters (~400 ft.) long - from the assembly site at the Port of Coeymans to the roll-on location, where it was loaded onto a barge for the next stage of its journey.
These sections will eventually replace the century-old Portal Bridge, a key link between Newark, New Jersey, and New York City. 
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[This photo is good enough that I noticed the SPMT is part of the load. I wonder why the false work is asymmetric.]

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(new window) Boats can be restricted, but it requires government officials that are willing to use their brains. Sailboats can go on the Chicago river just twice a week in the Spring and Fall. And they can go only to the lake in the Spring and from the lake in the Fall. Barge operators use the river year round, but they are required to use towboats with retractable pilothouses. And I'll bet that when they move cranes on a barge to a construction site that they don't do it during rush hour.


Jul 10, 2024: Halfway done, and it is on time and on budget.
3:03 video @ 0:47


Jul 6, 2024, just over 50% complete
3:01 video @ 0:41

A 13:15 video discussing the impact of this bridge construction on tug traffic. It does have some interesting timelapse video in some parts as he talks about the issues. It is not just a talking head.

Nov 16, 2024
2:10 video


Sunday, January 27, 2019

Bridges across the Mississippi River at Winona, MN and log rafts

1892 Horse and Wagon Bridge: (Bridge HunterHistoric BridgesJohn A. Weeks III; see "delicate" truss bridge in some of the photos below. The original wood trestle was replaced by a concrete open-spandrel arch, Satellite)

1871 C&NW Railroad Bridge: (Bridge HunterSatellite, the piers still stand in the backwater.)

1899 + 1928 C&NW Railroad Bridge, abandoned 1977: (Bridge HunterJohn A. Weeks III, good history; Main Channel Satellite, Backwater Satellite)

CB&Q+Green Bay and Western Railroad Bridge: (Bridge Hunter 1, Built in 1891; closed 1985; burned in 1989; removed in 1990; Bridge Hunter 2 has a better description; GreenBayRoute, 420' swing span; John A. Weeks IIIHAERSatellite)

1941 Vehicle Bridge: (Bridge Hunter; Historic BridgesJohn A. Weeks III; HAER; see satellite image below)

2016 Vehicle Bridge: (Bridge Hunter (For once, the plan is to restore the truss bridge and the two bridges will share the traffic load! Furthermore, the concrete-box girder design of the new bridge retains clear site lines of the old bridge.))

(Update: RoadTraffic-Technology article)

Photo from eBook, p 447-448 from Old C&NW Bridge Hunter
Opened in 1886. The draw span was 360' with clear openings of 160'.
 
Joe Fishbein posted
This is the original high bridge across the Mississippi River at Winona, MN.  It was replaced in 1941 by the cantilever truss I showed earlier.  The bridge 30 miles upstream at Wabasha, MN (replaced in 1986) had a similar approach, with two 90-degree bends bringing traffic into the downtown area.
Real photo postcard from my collection.

Pete Zimmerman posted
1898. Winona, Minnesota. Sternwheeler Lafayette Lamb. 8x10 inch glass negative, Detroit Publishing Company. (unknown photographer

At first, I thought this was a different exposure of the above photo. But the above has someone setting on a bench while the following has two people walking on the sidewalk.
Bridges Now and Then posted
Bridges over the Mississippi River at Winona, Minnesota, 1898. (Library of Congress)

I saved an image of the satellite view because the construction barges and new piers indicate a new bridge is being built. Fortunately, unlike Illinois, MN rehabilitates and keeps some of its truss bridges, including this one.
3D Satellite

Shorpy  (source)
[Note how the pivot pier aligns with the pier of the road bridge to form a straight navigation channel.]
Comments on the Shorpy site:
Bridge Over Troubled Water  Submitted by DaveA on Thu, 01/24/2019 - 10:35am.
Two bridges can be seen in this photo. One had been around for more than 25 years. The other, much bigger, was pretty new at the time. From a 1960s report for the Interior Department, addressing both:
        Although a railroad bridge connected Winona to the Wisconsin shore as early as 1871, the city had no direct highway access for another two decades. Teamsters made do with a ferry that carried them over the Main Channel to Latsch Island; there they disembarked onto a long wooden trestle that spanned the North Channel and the river's remaining expanse. In 1892, the ferry finally gave way to Bridge #5930, Steel, cantilever, through-truss design, the span was a municipally financed project designed to make Winona the main trade center for its Wisconsin neighbors. To retire the construction debt, the city administered the new "High Wagon Bridge" as a toll crossing.By the 1930s, auto traffic was making the now "old" high bridge obsolete, with its zigzag connection to an older North Channel wagon bridge a serious impediment.
A new span was designed and survives today about a quarter mile up river from the bridges seen in the photo above. Ironically, an updated form of the original North Channel wagon bridge survives for non-motorized traffic.

Answered my own question  Submitted by Mudhooks on Thu, 01/24/2019 - 9:31am.
The Winona Bridge had a swing span
“The bridge was built from the Wisconsin shore across the back channel to Island 72, now known as Latsch Island, across the main channel to the Winona shore. In the middle of the channel, a huge stone pylon was built up from the riverbed, and a steel and wood beam span was built on top of it. This section of bridge was designed to pivot on that center support, swinging parallel to the shore to allow steamboats, barges and log rafts to pass unimpeded. A tender's shack stood at the pivot point to shelter the rail roadman, who set the machinery in motion to swing the bridge closed when a train approached. At 363 feet, its swinging span -- the "draw" -- was the longest in the world.”
https://www.winonadailynews.com/special-section/pieces-of-the-past/thurs...
The eighth photo in a gallery
An early lithograph from the 1880s shows the railroad bridge and the ferry bridge that ran from Wisconsin to Latch Island.
[This would have been the RR bridge that proceeded the one in the above photo.]
The mention of "log rafts" in a Shorpy comment above was interesting. Did they really thread log rafts between the bridge piers? The article that contains this photo (see caption for link) says they put a steamboat at the front and back of a raft to steer the raft down the river. If you are interested in the logging industry that cut down the trees in Wisconsin by 1910, the article is well worth dealing with the single popup advertisement.
WinonaDailyNews, Winona County Historical Society
WinonaDailyNews, Winona County Historical Society
Malia Fox, cropped
Historic Wagon Bridge
CB&Q Photo from HAER MINN,85-WIN,1--8 from mn0091, cropped

Ted Hazelton posted
The Green Bay & Western Railway's bridge into Winona, Mn. This crossed over the Mississippi River between Wisconsin and Minnesota. In use for a little over 100 years. Abandoned and torn down in 1991. 
Dennis DeBruler
This is one of several available from the LoC. It looks like HAER MINN,85-WIN,1--9

Marvin Hielsen CB&Q photo, May 29, 1976 from the collection of Charles Tomashek during an excursion

John Weeks III, cropped
John explains that there was an emergency closure on June 3, 2008, after it was discovered the bridge had the same gusset problem that caused the collapse of I-35W. On June 14, they allowed cars and pickup trucks to use it. In addition to heavy vehicles, pedestrians and bicycles were still banned so that they could use the sidewalks to park equipment for bridge repairs. On July 22, the major structural repairs were done and they removed traffic restrictions. But the sidewalks remained closed until Oct. 3 because of additional repair work.
MnDOT
The Winona Bridge carries an average of 11,300 vehicles per day.
1942 Photo, first of 15 photos including some construction and ferry photos
In this 1942 photo, you can see the then-new Winona Bridge, left, the Railroad [C&NW] Bridge and the old wagon bridge before it was demolished in 1943.
[It is interesting that this much steel was allowed for a replacement during WWII.]

David Gulden posted
EWD . B WARNER at WINONA MINNESOTA
 
RoadTraffic-Technology

Roger Deschner photo from Bridge Hunter, cropped, License: Creative Commons Attribution-Share-Alike (CC BY-SA)
The two ends of the main span are about to meet in the middle in January 2016. The old bridge can be seen behind it, and the remains of the CNW - Winona Swing Bridge can be seen underneath it.
The approach spans are steel girder. The concrete box girders appear to be poured in place rather than lifting pre-cast segments at the ends. Some Winonans wanted "the demolition of the historic bridge in favor of building a new, beautiful arch bridge" even though it would cost $14m more. Accepting an ugly concrete bridge to help preserve the truss bridge caused trepidation in 2016 when MnDOT announced that they were putting the rehabilitation plans on hold because of estimated cost overruns. ($62m of the project's $142m was for the rehabilitation, but they thought it would cost $30m more. Part of the cost problem was a new engineering standard called HL 93.)  Everybody agreed that ending up with two ugly concrete bridges would be a bummer compared to the arches that Hastings and La Crosse got. The irony is that initially MnDOT wanted to tear it down; but, because it was Minnesota's last surviving through-truss bridge, federal law and regulators required studying the feasibility of saving it. [WinonaPost] The reduced the rehabilitation costs by replacing the approaches.
Roger Deschner photo from Bridge Hunter,  License: Creative Commons Attribution-Share-Alike (CC BY-SA)
The new bridge opened Aug 27, 2016. Because the paint on the truss bridge contained lead, before they sandblasted it and the rust off the old bridge, they had to enclose the truss "in tarps and creating a negative air pressure environment to contain paint, steel and concrete particles so they do not pollute the river or nearby ground." They will also add extra truss members so that it is no longer a "fracture critical" design.  [PostBulletin]

In 2016, they had made the decision to replace the approach spans, but they were debating if the new ones should be deck trusses like the old ones or beams like the new one. Since street views are typically more up to date, I checked it out. Obviously, they went with the choice of making the approaches look similar rather than replicating the deck trusses. But the difference in pier designs is interesting. Does the 12' trail on the new bridge require the more elaborate pier design?
Street View, July 2018

The ninth photo in a gallery
This photograph from 1935 shows the bridge in La Crosse, Wis., that was damaged when a car hit a girder, knocking a span of the bridge into the Mississippi River. The damage to the bridge, similar to the old wagon bridge in Winona, led to calls for the old bridge in Winona to be replaced.
[I doubt if a horse could take out a bridge girder. I wonder if a car could take out a girder in a more modern truss. I'll bet an 18-wheeler could. So rust is not the only reason to avoid "fracture critical" designs.]
The tenth photo in a gallery
[This closeup of the old wagon bridge allows us to see how spindly the truss was. At least it was steel instead of iron. The deck was made with wood.]

Why other towns with trusses got pretty new arch bridges while Winona got stuck with an ugly concrete bridge. Specifically, when La Crosse built their second bridge 10 years ago, the truss was not considered historic by the Federal Government.
3D Satellite of La Crosse's Cass Street Bridges
Actually, the concrete bridge does interfere with the view of the upstream side. But I can believe that it helps the downstream view.
RoadsBridges-general

A 2016 history of the efforts to fix the crossing. I haven't read it, but I include it for completeness.

They saved the truss  bridge!

RoadsBridges-rehabilitation
They used 3-D finite-element analyses, including some refined analysis, to determine how to install steel plating and high-strength post-tensioning bars to strengthen the bridge with minimum visual impact on the trusses. The strengthen bridge meets permit load limits, adds 50 years and removes fracture-critical truss members. The approach spans were replaced, but they used deck trusses for the new spans so the aesthetic of the bridge was preserved. They also improved the old piers to meet modern allision requirements by linking each old pier to a corresponding pier in the new bridge. This allows the new bridge to help the old bridge resist an allision by a tow. And the bridge opened five months ahead of schedule on July 1, 2019! Kudos to MnDOT and the companies they hired for paying attention to the public input and doing a good job.
RoadsBridges-rehabilitation

Satellite, accessed Feb 2020