1936 Seidersville Road (High Street): (Archived Bridge Hunter; Bridge Hunter; Historic Bridges; Satellite)
1936 Seidersville Road (High Street) Bridge
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| Street View, Jul 2024 |
"This bridge is currently closed to traffic, and it is located on Seidersville Road within the Bethlehem city limits. The road doesn't become High St. until it crosses the city line into Hellertown Borough which is on the east side of the former Conrail (originally originally the Reading's North Penn branch line) right-of-way." [Comment by Matt on ArchivedBridgeHunter_high]
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| 2018 photo by Royce and Bobette Haley via BridgeHunter_1936 |
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| HistoricBridges_high "This bridge is the only known through truss with welded connections in Pennsylvania. Constructed in 1935, the bridge is one of the earliest all-welded truss bridges in Pennsylvania. For these two reasons, the bridge is considered technologically significant and the bridge is thus eligible for the National Register of Historic Places., because it documents the transition from riveted connections to welded connections. The bridge also represents a transition from built-up beams to all-rolled beams in truss bridge construction, since the majority of bridge's members are composed of rolled beams with no riveting or welding. Some elements are built-up with welds, such as the bottom chord. The bridge also makes considerable use of wide flange beams, also called H sections, which became the standard after the traditional American Standard Beam i-beam fell from favor because of its troublesome sloped flanges. All of these features: the welds, the wide flange beams, and the heavy use of rolled beams, were all new for use in bridge construction when this bridge was built. What is interesting is how similar this 1935 bridge is to modern welded truss bridges built today in some states such as Ohio. Unlike other bridge types which often evolved and changed a lot over the years and decades, the welded truss bridge has changed very little in design and appear since it began to be used." |
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| 2018 photo by Royce and Bobette Haley via BridgeHunter_high |
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| 2018 photo by Royce and Bobette Haley via BridgeHunter_1860 |
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| Metrotrails posted The historic Walnut Street Bridge in Hellertown, Pennsylvania, which used to span the Saucon Creek. It now spans what had once been raceway for the 1761 Heller-Wagner Grist Mill. The Walnut Street Bridge was built in 1860 and retains much of its historic character. It was rehabilitated in 1999, and painted silver. Its design is quite interesting compared to others, made of cast and wrought iron. It was built by Beckel Iron Foundry of Bethlehem, Pennsylvania. The company was run by Charles Beckel and his son Lawrence Beckel. The bridge at some point was known as Wagner’s Bridge, probably because of the adjacent mill ownership, and later as “The Pony Bridge”. This too is a mystery, because Pony Truss bridges are usually low trusses with no connecting braces up top. The bridge had been rehabilitated in 1950, but vehicle use of the bridge ended in 1970. The odd decking probably wouldn’t have handled more modern vehicles. It was moved to the ground nearby, and eventually the aforementioned rehabilitation took place. Metrotrails shared |
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| HistoricBridges_1860 "The Walnut Street Bridge is one of the rarest and most important historic bridges in the United States. One of a mere handful of surviving through truss bridges with cast iron compression members, the Walnut Street Bridge has larger percentage of material that is cast iron than most of these bridges. In particular it is noted for its cast iron floorbeams, which is nearly unheard of, because floorbeams can be subject to tension and cast iron tends to display its brittle characteristics under tension. Finally, the bridge is also among the oldest all-metal bridges in the United States with a ca. 1860 construction date. The features the patented cast iron bottom chord connections as patented by F. C. Lowthorp, whose inventive skills were a part of several of the surviving cast iron truss bridges in the United States. The bridge itself was designed and constructed by the Beckel Iron Foundry of Bethlehem, Pennsylvania." |
"Only high-truss span built by
Beckel Iron Foundry known to exist.
Uses Francis C. Lowthorp's 23 June
1857 patented cast lower chord
connection. Deck beams on this and
two other existing Beckel ponytruss cast- and wrought-iron
bridges fabricated from cast rather than wrought-iron.
" [HAER_data]
The adjective "high-truss" is important because there are some pony-truss bridges by Beckel. Specifically, the Old Mill Bridge below.
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| HAER PA,48-HELLT,3--12 DETAIL VIEW OF LOWER CHORD CASTING - Walnut Street Bridge, Formerly spanning Saucon Creek, Hellertown, Northampton County, PA |
1858-2018 Meadows Road Bridge
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| LowerSauconTownship "Stone arch bridge construction predates the covered bridges and was the only technology available to the early settlers for longer and permanent spans prior to the introduction of metal truss bridge technology....Today the bridge is the oldest bridge in Lower Saucon Township and one of the oldest stone bridges in Northampton County. By the 1860's the Northampton County switched to building primarily iron span bridges." |
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| 2008 photo via BridgeHunter_1858 |
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| Street View, Aug 2016 |
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| Street View, Jul 2019 |
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| mcall "Construction continues Thursday, March 13, 2025, on the Meadows Road Bridge in Lower Saucon Township, which could open in June 2026. The span will replace the historic four-arched Meadows Road Bridge built in 1858, which was closed in 2018, when a 4-foot hole developed in its center, and then torn down about four years after that. (Monica Cabrera/The Morning Call)" |
1867 Old Mill Road Bridge
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| Street View, Jul 2024 |
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| 2017 photo by Royce and Bobette Haley via BridgeHunter_1867, cropped |
"Significance: One of two existing pony-truss
spans built by the Beckel Foundry.
Both used variations of Francis C.
Lowthorp's 23 June 1857 and 13
March 18 60 patented cast lower-chord connections. The Old Mill
and the Walnut Street [earlier in these notes] bridges
incorporate unusual cast-iron beams
to support decks." [HAER_data]
"The Old Mill Road Bridge differs from the Walnut Street Bridge in terms of member design. While the Walnut Street Bridge has circular-shaped members, the Old Mill Road Bridge has octagonal shaped members. Further, the cast iron top chord connection boxes on the Old Mill Road Bridge have a beautiful decorative flower shaped design on their faces. Also, unlike the Walnut Street Bridge, the Old Mill Road Bridge features a more traditional bottom chord consisting of eyebars connected by a pin. The Old Mill Road Bridge retains its cast iron floorbeams, however modern floorbeams were added below the original floorbeams. The pier at the center of the bridge is apparently the original stone pier encased in concrete." [HistoricBridges_1867]
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| HAER PA,48-HELLT,2--5 VIEW LOOKING NORTHEAST SHOWING WEST SIDE DETAIL OF BRIDGE - Old Mill Road Bridge, Spanning Saucon Creek, Old Mill Road, Hellertown, Northampton County, PA |
