Wednesday, April 21, 2021

1840+1893 Trail/NS/(Southern+L&N) Bridges over Tennessee River at Florence, AL

(Bridge Hunter; Historic Bridges; HAERSatellite)

The piers may date back to 1840. They are certainly older than 1893. 1893 is when the new steel trusses were built because a train wreck took out both the rail (upper) and wagon (lower) decks in 1892. In 1963 they replaced the swing span with a lift span. In 1993, Norfolk Southern moved this lift span to their Wabash bridge over the Mississippi River at Hannibal, MO and gave the rest of the bridge to a preservation organization, the Old Railroad Bridge.

Kevin Lackey posted
The Robin with 18 loads at Wilson Dam on the Tenn River
[This tow will go through the 1924 Lock #1 one barge at a time.]

The plaques posted on the trail by the Old Railroad Bridge are the best (concise) history I have come across. It is too bad that I could not find this text on their web site.
George Dawson, Apr 2021

George Dawson, Apr 2021

This 1936 topo map indicates that both Southern and L&N used the bridge.
1936 Florence Quadrangle @ 1:24,000

When they built the new 110' x 600' x 100' lock in 1959, they also built a wider canal that took some of the bend out of the downstream entrance and they forced the replacement of the swing span with a lift span by 1963.
1957 Florence Quadrangle @ 1:24,000

HAER AL-204-5
5. Lift span, looking southeast - Tennessee River Railroad Bridge, Spanning Tennessee River at Alabama Highway 43, Florence, Lauderdale County, AL

I labeled these notes "bridgeRare" because Nathan Holth (Historic Bridges) said so. Specifically: "the surviving spans are rare double-deck, pin-connected Warren truss spans." I don't think double-deck bridges were rare back then because an accommodation for wagon traffic was typically included when a railroad bridge was the first bridge across a major body of water. Although it was more typical to add the wagon decks on the sides rather than underneath. I think what is rare is "pin-connected Warren" trusses. Pin-connected is an old truss construction technique whereas Warren trusses are a relatively new truss design. Most pin-connected trusses used the Pratt design. This photo gives us a good view of the truss and its pin connections as well as the cut-stone piers.
Brian Cameron, Jun 2018

More evidence that 2019 was very wet in the US. Note that the water is at the top of the dolphins that are downriver from the end of the bridge.
Pine Grove Church of God, Mar 2019

This shows that when the water is near the top of the dolphins, it is also near the top of the crossover of a main pier (upper-right corner) for the O'Neal Bridge.
Toni Roxane Barnes, Feb 2019

This photo confirms that we can normally see much more of the dolphins than just the plants growing out the top of them.
Megan Thornton, Oct 2020

Another view that includes the dolphins. To the left of the dolphins is the Florence Canal that goes to the Wilson Locks.
Street View

This photo shows that some of the cut-stone piers have had extensive repairs, but not all of them. I didn't notice the concrete coated piers in the other photos.
Jay Patterson, Aug 2020

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