Thursday, February 16, 2012

the 1886 B&O Susquehanna Bridge, Havre de Grace, Maryland


This bridge built by the Baltimore and Ohio in 1886 was proposed as follows in a report:

"It is the determination of the company that it shall be of the most substantial, safe and durable character. It will be 6,346 feet [1,934 m] in length, 94 feet [29 m] above low mean tide, and will rest on eleven granite piers, having their foundations on the bed-rock of the river... The foundations for six of the piers have been difficult, reaching, as they do, a depth of 85 feet [26 m] below low water, and necessitating the use of caissons, with air chambers, in which the men, engaged in removing the debris in order to reach bed-rock, have worked under a pressure of 37 pounds per square inch [260 kPa]."

The bridge consisted of the following segments: a 212-foot (65 m) western approach viaduct, four 480-foot (150 m) Whipple deck truss spans, a 520-foot (160 m) through truss span over the western navigation channel, a 200-foot (61 m) deck truss span, a 1,942-foot (592 m) viaduct over Garrett Island, one 380-foot (120 m) and one 520-foot (160 m) Whipple deck truss spans, a 380-foot (120 m) through truss span over the eastern navigation channel, and finally a 242-foot (74 m) eastern approach viaduct. The eastern approach also crossed the PRR's Columbia and Port Deposit Railroad. Unlike the remainder of the Philadelphia line, the bridge contained only a single track.

It was opened with a ceremonial train on 11 May 1886 and freight operations began on 25 May; passenger operations followed on August 23. The first Washington to New York train to the use the new route crossed on December 15. Starting in 1890, passenger trains that used the bridge were marketed under the name Royal Blue Line.

By 1907, however, it was necessary to build a new bridge which was opened in 1910 and is still in use on the CSX system.

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