Tunkhannock Creek Viaduct (also known as the Nicholson Bridge and the Tunkhannock Viaduct) is a concretedeck arch bridge on the Nicholson Cutoff rail segment of the Norfolk Southern RailwaySunbury Line that spans Tunkhannock Creek in Nicholson, Pennsylvania. Measuring 2,375 feet (724m) long and towering 240 feet (73.15m) when measured from the creek bed (300 feet (91.44m) from bedrock), it was the largest concrete structure in the world when completed in 1915[3] and still merited "the title of largest concrete bridge in America, if not the world" 50 years later.[4]
The DL&W built the viaduct as part of its 39.6-mile (63.7km) Nicholson Cutoff, which replaced a winding and hilly section of the route between Scranton, Pennsylvania, and Binghamton, New York, saving 3.6 miles (5.8km), 21 minutes of passenger train time, and one hour of freight train time. The bridge was designed by the DL&W's Abraham Burton Cohen;[6] other key DL&W staff were G. J. Ray, chief engineer; F. L. Wheaton, engineer of construction; and C. W. Simpson, resident engineer in charge of the construction. The contractor was Flickwir & Bush, including general manager F. M. Talbot and superintendent W. C. Ritner.[7]
The bridge was also listed on the National Register of Historic Places on May 3, 1977.[8][9] In 1990, the National Railway Historical Society placed a historical plaque on the structure noting its size as the world's largest concrete bridge, completing the Summit cut-off project for the Delaware, Lackawanna and Western Railroad.
History
Construction on the bridge began in May 1912 by excavating all 11 bridge piers to bedrock, which was up to 138 feet (42m) below ground. In total, excavation for the viaduct removed 13,318,000 cubic yards (10,182,000m3) of material, more than half of that rock.
Almost half of the bulk of the bridge is underground. At mid-construction, 80,000 cubic yards (61,000m3) of concrete had gone into its substructures, and it was estimated that construction would require 169,000 cubic yards (129,000m3) of concrete and 1,140 short tons (1,030t; 1,020 long tons) of steel.[10] The steel estimate proved accurate; the bridge ultimately used a bit less concrete than expected: 167,000 cubic yards (128,000m3),[7] making the total weight approximately 670,000,000 pounds (300,000,000kg).
The bridge was dedicated on November 6, 1915, along with the opening of the Nicholson Cutoff.[11][12]
Construction photos along with a short history of the bridge were published by the Nicholson Area Library in a brochure in 1976.[13] It was listed on the National Register of Historic Places on April 11, 1977.[1]
Since 1990,[14] the local community has celebrated the building of the bridge on the second Sunday of September with "Nicholson Bridge Day", a street fair, parade, and other activities.[15] The 100th-anniversary celebration was held in September 2015.[16]
ASCE recognized the bridge as "not only a great feat of construction skill" but also a "bold and successful departure from contemporary, conventional concepts of railroad location in that it carried a mainline transversely to the regional drainage pattern, effectively reducing the distance and grade impediments...".[18] At the time, the decision was made to build the bridge out of reinforced concrete, railroad engineers had little experience with this material.[18]
The bridge was also listed on the National Register of Historic Places on May 3, 1977.[8][9] In 1990, the National Railway Historical Society placed a historical plaque on the structure noting its size as the world's largest concrete bridge, completing the Summit cut-off project for the Delaware, Lackawanna and Western Railroad.
Anon. "NRHP assessment for Tunkhannock". National Archives at College Park - Electronic Records (RDE). Department of the Interior. National Park Service. Retrieved 10 September 2019.
Herbert Hands, ASCE news release dated January 22, 1975
Further reading
Plowden, David (2002). Bridges: The Spans of North America. New York, NY: W.W. Norton and Company.
Taber, Thomas Townsend; Taber, Thomas Townsend III (1980). The Delaware, Lackawanna & Western Railroad in the Twentieth Century. Vol.1. Muncy, PA: Privately printed. ISBN0-9603398-2-5.
A Thing Colossal and Impressive, article by Pennsylvania Center for the book with extensive source listing for the structure.
Share this article:
This article uses material from the Wikipedia article Tunkhannock_Viaduct, and is written by contributors.
Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.