Walpack Center Bridge

Information and Findings From New Jersey's Historic Bridge Inventory

 Summary

The pin-connected Pratt pony truss bridge is supported on ashlar abutments. In 1944 the trusses were strengthened with the addition of welded plates to the vertical, diagonal, and lower chords. Outriggers were added, and channel sections were welded to the floor beams. The span is one of the few documented truss spans in the county, and it was fabricated by a notable company. The bridge was constructed within the period of significance of the district, and it is a contributing element under Criterion C.

Setting/Context

The bridge carries a 1-lane road over a small stream in a wooded area located within the Delaware Water Gap National Recreation Area. The span is within the borders of Walpack Center Historic District, which is significant as a well-preserved example of an early rural service center dating from the mid-1800s to the early 1900s. Located in an isolated valley, the village marketplace, which was supported by local farmers, diminished with the advent of the automobile.

Physical Description

The pin-connected Pratt pony truss bridge supported on ashlar abutments spans 70' and carries an 11'-6" width roadway. The truss members are standard sections, and they have been strengthened with welded plates. Outriggers were added to the trusses, and channel sections were welded to the floor beams. The deck was replaced with a metal grate deck. The dates of the alterations to the span are not documented. No plans for the bridge were located.

Historical and Technological Significance

The Pratt pony truss bridge, located in the Walpack Center Historic District, was constructed in 1889 by the Groton Bridge & Manufacturing Co., as is documented on a plaque located on top of one of the trusses. The bridge is significant because it is a documented example of an uncommon bridge type constructed by a noted bridge manufacturer. It was built within the period of significance of the district, and it is a contributing element (Criteria A & C). The Groton Bridge & Manufacturing Company, of Groton, New York, was formed in 1877 under the name of the Groton Iron Bridge Company. The company was formed as the result of a merger between the Groton Iron Works, a blacksmith shop owned by Charles and Lyman Perrigo, and the Groton Separator Works, a manufactory of agricultural equipment owned by Daniel Spencer and Frederick Avery. It became a major bridge manufacturer primarily constructing small Pratt truss bridges in New York State. The firm was run by Ellery Colby and Frederick Avery during its first ten years of operation. Colby was a significant figure in New York State bridge building who later formed the Owego Bridge Company. In 1887, the name of the firm was changed to the Groton Bridge and Manufacturing Company, and it expanded operations. During this period, the company constructed many spans throughout the nation, the largest being an eleven-span bridge in Little Rock, Arkansas in 1896, and a multi-span crossing of the Anacostia River at Pennsylvania Avenue in Washington, D.C. in 1890 (replaced in 1936 by the John Phillip Sousa Bridge). In 1899, the firm became part of the American Bridge Company, and continued operation, primarily in New York State, until it folded in 1920. The Walpack Center Historic District is an example of one of the first forms of urbanism in the country, the rural service center. Rural service centers thrived from the mid-nineteenth century through the early twentieth century, providing a marketplace for the local agricultural industry. Walpack Center was geographically isolated, located in a valley between two ridges of the Kittatinny Mountains. The geography of the area dictated a need for a local marketplace because travel was difficult. The farmers in the area depended on the local market to sell their goods, and the local people depended on it to obtain goods. With the advent of the automobile, travel became easier and this interdependence no longer existed. The town did not expand with increased transportation, as other service centers did, because of its isolated location. Building in the town came to almost a complete end in the early 1900s, and the town retains much of its late 18th century character. The architecture is not sophisticated, but rather ordinary, reflecting the lifestyle of the rural town during its peak. The bridge is located at the edge of town within the historic district, and it was constructed in 1889, during the period of significance.

Boundary Description and Justification

The bridge is an eligible contributing resource to the National Register-listed Walpack Center Historic District (1980). The bridge is completely within the boundaries of the historic district delineated in the nomination (refer to NR Sussex Co. File at HPO). The eligible resource includes the bridge as well as its surroundings.

Sources

Pamela Thurber, "The Groton Iron Bridge Company," Historic Ithaca & Tompkins, NY, Newsletter Fall 1983, New Series Vol. 1,2, pp. 1-4. Office of New Jersey Heritage. Sussex County, Walpack File.

Bridge Considered Historic By Survey: Yes