Old+1954 Main Street and 1857+1990 Covered Bridges over Piscataquls River near Gilford, ME

Old Main: (Archived Bridge Hunter; Bridge Hunter)

1954 Main: (Satellite)

Covered: (Archived Bridge Hunter; Bridge Hunter; Satellite)

Bridges Now and Then posted
"Iron Bridge collapse, Guilford, Maine, 1954." (Guilford Historical Society)

The smokestacks imply that if these mills used hydro power, they were converted to steam power. (This view is from the current Main Street Bridge. I'm guessing from the age of the bridge that the girders are steel instead of concrete.)

I found this covered bridge while looking for the Gilford Bridge on a satellite map.

J. Stephen Conn Flickr, License: Creative Commons Attribution-NonCommercial (CC BY-NC)
Lowe's Covered Bridge, Guilford, Maine
 This bridge, built in 1857, was washed away by the flood of April 1, 1987. A modern covered bridge, patterned after the original, was built on the original abutments in 1990. The bridge has a clear span of 120 feet [36.6m] over the Piscataquis River. It is located just off State Route 15 south of Guilford Village.

2016 photo by John Loxton via BridgeHunter

Julie Richard Nadeau, Jul 2024

1947,1978 US-340 Sandy Hook (Harpers) Bridge over Potomac River near Loudoun Heights, VA

(Archived Bridge Hunter; Bridge Hunter; Historic Bridges; Satellite)

This 2,251' (686m) long bridge has 12 190' (58m) spans. [HistoricBridges]

2015 photo by Antony 22 via BridgeHunter

This view has a higher river level.

May 16, 2014 photo by Jodi Chrstman via BridgeHunter

There are four continuous truss units made of three spans each. [HistoricBridges]

In the upper-right corner we see the ends of two of the continuous units.

Joshua Gregoir, Oct 2022

Metrotrails posted

The Sandy Hook Bridge over the Potomac River seen below the Chesapeake and Ohio Canal in Sandy Hook Maryland. 

The Metal Continuous 11 Panel Rivet-Connected Warren Deck Truss Bridge was built in 1946 by the Bethlehem Steel Company.

Metrotrails shared

Metrotrails posted with the same description as above.

1955,2008 Roosevelt (Welfare) Island Bridge over East River in New York, NY

(Archived Bridge Hunter; Bridge Hunter; Historic Bridges; Satellite)

Boat View, Nov 2016

HistoricBridges
The 958' (292m) long bridge has a main span of 418' (127m).
"This vertical lift bridge provides the only direct vehicular access to Roosevelt Island. The bridge does not operate for boats very often, reportedly most openings occur during the United Nations General Assembly when the west channel of the East River is closed to marine traffic for security. The bridge cost $6,498,255.13 to build, and opened May 18, 1955."
[I wondered why boats would use the east channel.]

This shows why the length of the bridge is over twice that of the main span. It has a viaduct over industry on the east side. Consequently, the span has significant clearance when closed.

2008 photo by Michael Minn (michaelminn.com) via BridgeHunter

2021 photo from the Queensboro Bridge by Geoff Hubbs via BridgeHunter

CSX/B&O Bridge over Wills Creek in Hyndman, PA

(Archived Bridge Hunter; Bridge Hunter; no Historic Bridges; HAER; Satellite)

Street View, May 2021

The 1916 bridge must have replaced these two spans.

Jackson-Township historical preservation posted
Double Railroad Bridges for the B & O (Baltimore & Ohio) Railroad in the town of Hyndman, Bedford County in the early 1900's.
Jackson-Township historical preservation posted via Dennis DeBruler
Double Railroad Bridges for the B & O (Baltimore & Ohio) Railroad in the town of Hyndman, Bedford County in the early 1900's.
Paul Manges: These two spans were replaced by a single two track span in 1910 which is still standing. [Bridge Hunter dates the replacement as 1916.]
Scotty Fahnestock shared

HAER PA,5-HYND,2--1
GENERAL VIEW OF PORTAL - North Hyndman Bridge, Baltimore & Ohio Railroad spanning Wills Creek, Hyndman, Bedford County, PA

HAER PA,5-HYND,2--2
DETAIL OF NAMEPLATE; IT READS: "BUILT BY KING BRIDGE COMPANY, CLEVELAND, O., 1916"

"Significance: This bridge was built by the King Bridge Company of Cleveland, Ohio, one of the nation1 s leading nineteenth-century bridge manfaucturing concerns. King Bridge was one of the few large bridge building companies to survive the merger movement of 1900-01 when the giant American Bridge Company, a subsidiary of the U.S. Steel Corporation, was formed. The B&O's bridge at Wills Creek is likely one of the last King Bridge Company spans erected in Pennsylvania." [HAER_data]

1944/44 Hyndman Quad @ 62,500

Hyndman was at the base of Sand Patch Grade over the Allegheny Mountains. The small yard on the south side of town was for helper engines. The topo map is wrong because there was a ladder at both ends of that yard.

Bill Rettberg Jr. posted via Dennis DeBruler
Good overview of Q tower and the helper station in the background, at Hyndman Pa. Eastbound is just coming off of Sand Patch grade.

James Anders posted via Dennis DeBruler, cropped

28 hour replacement of the Santa Fe Trestle over Denton Creek north of Justin, TX

(Satellite)

The trees hide over half of the 600' (183m) trestle.

Street View, Dec 2024

BNSF Railway 1:00 video (source) @ 0:00

In just 28 hours, BNSF crews safely demolished an 85-year-old wooden trestle bridge and built its 600-foot steel-and-concrete replacement north of Justin, Texas. More than 40 team members worked around the clock to ensure the new structure was ready for service. After months of planning, teamwork and engineering precision, everything came together in a tightly choreographed operation that showcased the pride of railroading.

See a lightning-fast timelapse video of 28 hours of work condensed to one minute at https://www.youtube.com/watch?v=HfknlgO4-Pw.

[Some comments observed that they had already driven all of the steel piles through the old deck structure and had cut them to length.]

Here we can see a couple of the new steel-pile bents.

@ 0:10

The small precast concrete structures to the right of the excavators would be the pier caps. The other structures are half of a span.

@ 0:19

It looks like they used juice (hydraulic) cranes for the pier caps and lattice cranes for the spans.

@ 0:21

Here a half-span is being slewed into place.

0:23

The length of the bridge is needed to pass the Denton Creek when there are rains.

@ 0:36

That tamper has his target out, so he is probably close to a final pass.

@ 0:47

The apparatus hanging out of the rear of the truck is an arc welder. The are welding the joints between track sections. The sections are two rails with their ties that have been preassembled so that they can be pulled into place after the spans have been built.

@ 0:49

After the welding, they did more tamping. I wonder if they also used a dynamic stabilizer to allow track speed after they were done. And I wonder what the track speed was before and after the replacement. Tracks on stone ballast should support a lot higher speed limit.

@ 0:53

I guess they did not use a stabilizer because this Amtrak train is creeping over the bridge.

@ 0:53

About a third of the construction time was dumping ballast and doing tamper passes.

1:00 video @ 0:39
Timelapse of BNSF bridge replacement! 28 hours of work in 1 minute

There is a parallel route, so detours during the outage would have been rather easy.

BNSF via Dennis DeBruler

1952+2010 I-76 Bridges and C. W. Bill Young L&D on Allegheny River near Oakmont,PA

1952 (Archived Bridge Hunter; Bridge Hunter; Historic Bridges)

2010: (Archived Bridge Hunter; Bridge Hunter; Satellite) Pennsylvania Turnpike

Dam: (Satellite)

Postcard via BridgeHunter_1952

This is a view of the C. W. Bill Young Lock & Dam through the B&LE Bridge from the I-76 bridge.

Street View, Nov 2024

A view of the lock & dam from the B&LE Bridge.

Robert Suchevits, Aug 2016

The 1952 bridge was just to the left (east, upstream) of the new bridge.

Street View, Jun 2025

It looks like the 2010 bridge is made with concrete segmental box girders.

Street View, Jun 2025

During construction of the 2010 bridge

Global Earth, Oct 2008

After the switchover, but before the demolition.

Global Earth, Jul 2010

That is the B&LE Bridge in the background.

USACE, Pittsburgh District posted

Did you know C. W. Bill Young Locks and Dam, upstream of Pittsburgh on the Allegheny River, has a quirky little feature hiding in pla#navigation 

Well, had…

Back in the 1930s when the facility was being built, engineers made a one-fifth scale model of a modified taintor gate on the fixed-crest dam. It was meant to help test new ideas for future projects, but apparently it didn't make the cut because the experimental gate no longer there. 

That’s why one section of the dam looks a little different than the rest - giving the water flow there a slightly different look.

Winn Gnutt: It was a model of the Sydney gate installed at Hemsworth [Emsworth] when the gates were installed on the original fixed crest dam. Then locks one(1) on both the allegheny and money were removed.

I didn't see the notch in most of the images, but it looks like this images shows it near the north shore.

Global Earth, Jun 2016

A decent view of the lock.

HAER PA,2-OAK.V,1--1 via Dennis DeBruler

1889 Hopkinton Covered Railroad Bridge over Contoocook River in Contoocook, NH

(Archived Bridge Hunter; Bridge Hunter; HAER; Satellite)

"Built 1889, Washed off abutments and restored 1936 & 1938; Abandoned 1962; Restored 1990; Major rehab 2003; Fire suppression and fire proofing 2009; Removal of center shelving 2017; Erosion control fixes, minor siding repairs, new staining 2019." [BridgeHunter]

"SIGNIFICANCE: "The Contoocook Railroad Bridge is one of eight surviving covered bridge in the United States. It is an excellent example of the double-web Town lattice truss used by the Boston & Maine Railroad in the late nineteenth century." [HAER_data]

They must have forgotten the adjective "railroad" in front of "covered bridge" because I have noted way more than eight covered bridges in the USA.

Street View, Oct 2023

It was stained about a year after this photo was taken.

Street View, Aug 2018

2015 photo by Mike Garland via BridgeHunter

Boston & Maine acquired the original Concord & Claremont Railroad in 1887.

2019 photo by Steve Lux via BridgeHunter

HAER NH-38
INTERIOR, LOOKING WEST. - Contoocook Railroad Bridge, Spanning Contoocook River at former Boston & Maine Railroad (originally Concord & Claremont Railroad), Hopkinton, Merrimack County, NH Photos from Survey HAER NH-38

HAER NH-38
Contoocook Bridge, Title Page - Contoocook Railroad Bridge, Spanning Contoocook River at former Boston & Maine Railroad (originally Concord & Claremont Railroad), Hopkinton, Merrimack County, NH Drawings from Survey HAER NH-38
[There are seven more diagrams.]

There are a couple of layers of trusses on both sides.

iisabelle Humphres, Apr 2023

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