Enola Low Grade Trail - Safe Harbor Bridge

Photos 

Photo taken by Sean McDonnell

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BH Photo #220836

Map 

Street View 

Description 

This was once a part of the Atglen & Susquehanna Branch, a Pennsylvania RR low-grade freight bypass of Lancaster between Columbia and Atglen, and used to carry several freight trains a day between the Harrisburg area and points east; Conrail acquired PRR successor Penn Central in 1976 and later shifted through freight trains off the ex-PRR Harrisburg-Philadelphia-Trenton routes in favor of former Reading RR routes. Conrail abandoned this bridge, and the entire Atglen & Susquehanna, around 1988. Currently it is a part of the planned Enola Low Grade Trail which extends from just outside Harrisburg to Paradise, Pa.

PENNSYLVANIA RAILROAD, SAFE HARBOR BRIDGE (HAER No.PA-531) 

Description and History
In 1902, the Pennsylvania Railroad (PRR) made plans to build a new low-grade freight line across Lancaster County, a decision motivated by steep grades on its four-track main line between Philadelphia and Harrisburg. Called the Atglen & Susquehanna Branch (A&S), or simply the Low Grade, it diverged from the main line at Parkesburg and passed south of Lancaster, through Quarryville and Martic Forge, to Shenk’s Ferry on the Susquehanna River.

The A&S then paralleled the existing Columbia & Port Deposit Branch (C&PD) of the Philadelphia, Baltimore & Washington Railroad (a PRR subsidiary) along the river's east bank. At Shock's Mills it crossed the Susquehanna on a new stone arch bridge and proceeded along the west bank to rejoin the main line at Marysville. Construction of the line, which consumed "over three and a half years, $19.5 million, and reportedly more than 200 lives," is a story in itself, amply covered by historian Frederic H. Abendschein.

The A&S was but one of a number of improvements to freight operations in eastern Pennsylvania during me admmistration of PRR President Alexander J. Cassatt. Other items proposed by Cassatt in 1902 included grade reduction on the Trenton Cut-Off and construction of the Philadelphia & Thomdale Branch, the completion of which provided a continuous freight bypass around Philadelphia. The 1902 plan let a gap of about ten miles from Thomdale to Parkesburg, between which freight trains shared the main line with passenger traffic. Although the gap was never closed, the Philadelphia bypass and the A&S together constitute initial segments of "a low grade route stretching from the eastern seaboard to the midwest," a vision which Abendschem attributed to former PRR President J. Edgar Thomson, who served from 1852 to 1874.

Construction on the A&S began with the Shock's Mills Bridge in late 1902. As work proceeded, a 1904 flood turned over the six-span stone arch bridge that carried the C&PD tracks over the Conestoga River. Rather than rebuild this bridge, PRR evidently decided to incorporate its replacement into a new bridge for the A&S. As the two lines travel south from Columbia, the C&PD descends to follow the river while the A&S ascends in preparation for its turn to the east. (Where the lines diverge at Shenk's Ferry, these two lines are 150'-0" apart in elevation.) The new Conestoga River bridge was therefore designed with two levels, with the C&PD's two tracks at 55'-0" above the 1905 river level, and A&S's two tracks 92'-0" higher and 96’-0” to the east. The C&PD spans, riveted deck plate girders 98'-6", 98’-0", and 98'-6 long, comprise the entire 295'-0" length of the lower level. At the upper level, the A&S spans include not only a 300'-0" pin-connected Pratt deck truss over the river, but also plate-girder viaducts on steel trestle bents, nine spans totaling 480'-0" on the north approach, and seventeen spans totaling 780'-0" on the north. The high stone piers supporting the 300’-0” truss are monolithic with the lower level abutments.

PRR's wholly-owned subsidiary, Pennsylvania Steel Co. of Steelton, fabricated all of the steel work, which was erected by the contractor on this section, H. S. Kerbaugh, Inc., during 1905. Construction photographs show that the high stone piers and falsework for the 300'-0" truss were built concurrently. During this time, the C&PD used a temporary wooden trestle off to one side. Erection first began on the 300'-0" truss, aided by a traveler. Shortly thereafter, additional traveling cranes were employed for the north and south approach viaducts, working from the abutments toward the river. Almost all of the high-level erection had been completed before crews began work on the low-level girders. The A&S opened to traffic in July 1906, and the C&PD, which had suffered numerous diversions and interruptions during construction, returned to regular service that August.

Construction of the Safe Harbor Dam in the 1930s raised the river's level considerably, prompting PRR to raise the C&PD grade. Maintenance records indicate that Belmont Iron Works raised the tower spans 4'-0" and installed reinforced concrete bridge seats. While the former G&PD continues to see freight traffic, then-owner Conrail removed tracks from the upper level in 1990, after abandoning this portion of the former A&S.

Facts 

Overview

Abandoned bridge on former PRR low-grade freight line, it crosses over the Congestoga Creek and passes by the Safe Harbor Powerplant

Location

Safe Harbor, Lancaster County, Pennsylvania

Status

Abandoned

Future prospects

Current owner is Norfolk Southern

History

Built 1904-06, Abandoned to rail service 1988

Builders

- H.S. Kerbaugh Inc. (Erectors)
- Pennsylvania Steel Co. of Steelton, Pennsylvania (Fabricator)
- William H. Brown (Chief Engineer)

Railroads

- Conrail (CR)
- Penn Central Railroad (PC)
- Pennsylvania Railroad (PRR)
- Rail-to-trail

Design

300-foot pin-connected Pratt deck truss main span; supplemented by plate girder viaducts on steel bents – nine spans measuring 480 feet to the north and seventeen spans to south measuring 780 feet.

Dimensions

Length of largest span: 300.0 ft.
Total length: 1,560.0 ft.

Also called

Enola Low Grade Line (A&S Railroad) Steel Trestle
Safe Harbor Bridge
Safe Harbor Crossing
Powerhouse Bridge
The Harbor Trestle
Enola Low Grade Trail Conestoga Creek Bridge
Enola Low Grade Safe-harbor Crossing
Port Deposit Trestle

Approximate latitude, longitude

+39.92525, -76.38418   (decimal degrees)
39°55'31" N, 76°23'03" W   (degrees°minutes'seconds")

Approximate UTM coordinates

18/381716/4420377 (zone/easting/northing)

Quadrangle map:

Safe Harbor

Inventory number

BH 47614 (Bridgehunter.com ID)

Categories 

Update Log 

• August 14, 2017: New Street View added by Dana and Kay Klein
• November 1, 2013: New photo from Jodi Christman
• October 14, 2013: Updated by Daniel Hopkins: Renamed the proper current name
• October 13, 2013: Updated by Jodi Christman: Corrected GPS (this is the most eastern bridge which I mistakenly changed a few years ago)
• October 11, 2013: Updated by Luke Harden: Added categories "Conrail", "Penn Central Railroad"
• October 11, 2013: Updated by Jodi Christman: Corrected GPS (this is the most western bridge)
• February 21, 2013: Updated by Luke Harden: Fixed builders.
• February 21, 2013: Updated by Alexander D. Mitchell IV: Added builder info, link to sources, corrected data
• July 15, 2011: Updated by Daniel Hopkins: Added the Enola Low Grade info
• July 8, 2011: Updated by Daniel Hopkins: Updated informaiton about the Enola Low Grade Trail
• July 7, 2011: New photo from Luke Harden
• June 11, 2011: Updated by Alexander D. Mitchell IV: Description and overview corrected and expanded, creek name corrected
• May 27, 2011: Updated by Daniel Hopkins: Updated creek name
• May 26, 2011: Updated by Daniel Hopkins: updated history
• January 11, 2011: Added by Daniel Hopkins

Related Bridges 

• NS - Safe Harbor Bridge (Below)

Sources 

• Daniel Hopkins - chimera [at] clovermail [dot] net
• Alexander D. Mitchell IV
• Luke
• Sean McDonnell
• Michael Froio Photography - Blog entry on history of the rail line and bridges
• Jodi Christman - masterofchaos [at] outlook [dot] com
• HAER PA-531 - Pennsylvania Railroad, Safe Harbor Bridge, Spanning mouth of Conestoga River, Safe Harbor, Lancaster County, PA
• Dana and Kay Klein

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