SETTING / CONTEXT The well-preserved 3-span bridge, accessed by a steep descending curve, is located on a closed portion of road in a wooded setting. Some of the surrounding land is dedicated to green space by its corporate owners. The bridge was closed to vehicular traffic by the county because of constant disregard for weight limits and damage from vehicular impact. It is now a pedestrian and bicycle bridge. There are no plans to remove the bridge.
SUMMARY The documented and well-preserved riveted Warren pony truss is the longest of its type in the county and is one of the best preserved. It was fabricated by Berlin Construction Company of Berlin, CT, a firm that built riveted Warren trusses into the 1920s. The ashlar piers may predate the bridge, and they added to significance of the span. Warren pony trusses were the most common type of bridge in America prior to 1925, but it is not as common in New Jersey.
INFORMATION Bibliography: Darnell, Victor. Interview with Mary McCahon. 10/18/91. Mercer County Engineer's Office.
Physical Description: The 3-span bridge is composed of three sets of riveted Warren pony trusses supported on high ashlar abutments and piers. The substructure may well be from an earlier span. The inclined end posts and top chord are built up box members of channels and plate while the diagonals (there are no verticals) are toe-in channels that are either laced or connected by battens. Connections at panel points are riveted to gusset plates. The most unusual design detail of the bridge is the square-headed bolts that serve as the floor beam hangers. The hanger bolts pass through a plate riveted to the top of the lower panel point. The rolled I-section floor beams appear to be original, but the stringers were replaced in 1930. Repair work in the 1950s included replacing "rotted" gussets and bottom chord angles in kind. The original lattice railing survives. The bridge is well preserved in both setting and design, and it serves as a pedestrian bridge.
Historical and Technological Significance: The well-preserved 3-span riveted Warren pony truss is an important example of a oncecommon bridge type. One of three surviving Warren pony trusses in Mercer County, the Province Line Road bridge is the longest as well as most complete of the group. It was designed and fabricated by the Berlin Construction Company of Berlin, Connecticut in 1903. The Berlin Construction Company is an offshoot of the Berlin Iron Bridge Company, which was acquired by the American Bridge Company in 1900. When Berlin Iron Bridge Company, made famous by its lenticular truss bridges, was taken over, three executives formed a new company for the purpose of fabricating and erecting structural steel. Incorporated in New Jersey in 1900 and in Connecticut in 1905, the Berlin Construction Company leased a fabricating plant in Pottsville, Pennsylvania and maintained offices in New York and Boston. Its headquarters and fabricating yard, however, remained in Berlin, and the company produced building structural steel as well as bridges. It ceased bridge fabrication by the mid-1920s. According to bridge historian Victor Darnell, Berlin Construction Company's bridge work was dominated by straight-forward riveted Warren trusses. Original plans for the bridge survive in the Mercer County Engineer's Office. The bridge was designed by the Berlin Construction Company. The corporate history of the firm illustrates the dominant influence the American Bridge Company had on bridge fabrication at the turn-ofthe-century. As first J.P. Morgan and Company and then U.S. Steel acquired 50% of the nation's fabricating capacity, new firms were established in the wake of the reorganization. Berlin Construction, still in business as the Berlin Steel Construction Company specializing in building steel, was for a time able to be a profitable small fabricator making standardized designs. While not technologically innovative, the Province Line Road bridge stands as not only a well-preserved example of a small post-American Bridge Company fabricator but also a record of the history of technology at the turn of the century. The riveted Warren pony truss, according to J.A.L. Waddell, was the most common bridge type in the country prior to 1925.
Boundary Description and Justification: The bridge is evaluated as individually significant, and the boundary is thus limited to the substructure and superstructure itself. While the wooded setting contributes to the integrity of setting, the acreage does not appear to have significant historical value. The road itself once served as the boundary between the east and west Jersey provinces, but it has lost its integrity due to modern development.