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WARREN COUNTY BRIDGE No. 19005 HAER No. NJ-86 (Lock Street Bridge) Lock Street over the Lopatcong Creek Phillipsburg Warren County New Jersey PHOTOGRAPHS WRITTEN HISTORICAL AND DESCRIPTIVE DATA HISTORIC AMERICAN ENGINEERING RECORD National Park Service Northeast Region U.S. Custom House 200 Chestnut Street Philadelphia, PA 19106 HISTORIC AMERICAN ENGINEERING RECORD WARREN COUNTY BRIDGE NO. 19005 (Lock Street Bridge) HAER No. NJ-86 Location: Lock Street over the Lopatcong Creek Phillipsburg, Warren County, New Jersey UTM: 18.486260.4503460 Quad: Easton, N.J.,PA. 1: 24,000 Date of Construction: Substructure: Unknown Superstructure: Circa 1900-1910 Alterations and Additions: circa 1927, 1950- 1960, 1980, 1985 Engineer: Unknown Present Owner: County of Warren Wayne DuMont, Jr. Administration Building Belvidere, New Jersey 07823 Present Use: Vehicular bridge To be demolished Significance: The bridge crosses over the Lopatcong Creek and permits access from the Route 22 corridor to the east into the Town of Phillipsburg. The bridge, which is a steel Pratt Truss with pin connections, is a representative structure for the span length and time period in which it was built. Project Information: An evaluation (1980) advised replacement of the structure. This documentation recommended by the Office of New Jersey Heritage, serves to mitigate the negative effect of the removal of the bridge. Elizabeth S. Calhoun Mace Consulting Engineers, P.C. 1011 Route US 22 Phillipsburg, New Jersey 08865 WARREN COUNTY BRIDGE NO. 19005 (Lock Street Bridge) HAER No. NJ-86 (Page 2) I. DESCRIPTION OF BRIDGE AND SETIING: Warren County Bridge No. 19005 (Lock Street Bridge) was constructed to carry vehicular traffic across the Lopatcong Creek. To the south, Lock Street runs parallel to the Lopatcong Creek and the Morris Canal. The bridge is located approximately two hundred feet northwest of the abandoned Morris Canal Incline Plane 10 West. This bridge originally spanned the main flow of the creek, while another bridge, a stone arch located approximately 130' to the south, spanned another part of the Creek. In recent times the channel through the stone arch bridge has been filled in and the Lock Street Bridge spans the entire width of the Creek. The area where the bridge is located is rural in nature, although it is in close proximity (one-half mile) to the more urbanized area of the Town of Phillipsburg. The approach roadway is narrow, approximately 15' on each side. On the southern approach the roadway is restricted by the abutment walls from the abandoned stone arch bridge and farther south by the creek bank on the east and on the west by a spring house, located approximately 400' south of the bridge, on the west side. On the northern approach the roadway width is restricted by the banks of the creek on the west side and by an embankment on the east side. The bridge abutments are sharply skewed from the roadway. This skew accommodates the creek to make the sharp turn immediately upstream of the bridge. Although the bridge was located close to the Morris Canal there is no documentation that would indicate that the Morris Canal and Banking Company was responsible for the construction of the bridge. The bridge is currently owned by the County, while the adjoining roadway is owned by the adjoining municipalities. The municipal boundary line follows the center of the road and bridge, with the Town of Phillipsburg being on the west and the Township of Lopatcong being on the east. During the time period when the Morris Canal was in operation, Lock Street serviced the Canal. The bridge crossing the Creek allowed vehicular and pedestrian access to both the lower and upper ends of the incline plane. Vehicles and/or pedestrians approaching the site from the south could cross the bridge to access the upper end of the plane, while vehicles and/or pedestrians approaching the site from the north could cross the bridge to access the lower end of the canal. In more recent times the bridge's primary purpose is to act as a vehicular connection between the Town of Phillipsburg in the south and the area to the east and north of the Town, specifically to Route US 22. From the north and east it serves as a secondary access to the southern end of the Town. WARREN COUNTY BRIDGE NO. 19005 (Lock Street Bridge) HAER No. NJ-86 (Page 3) 11. BRIDGE DETAIL A. GENERAL DIMENSIONS OF THE BRIDGE The bridge's clear span length is sixty-six (66') feet and the overall structure length is seventy-four feet (7 4'). The truss is composed of five panels, two on each end of the span thirteen feet three inches (13'-3") long and one in the middle of the span fifteen feet eleven inches (15'-11 ") long. The height of the span from the bottom pin connection to the top member connection is six feet (6'), thereby classifying it as a "pony" truss. The overall truss width from the centerline of the truss to the centerline of truss is sixteen feet ten inches ( 16' -1 O") and the deck width is fifteen feet eight inches (15'-8"). The clearance from the bottom of the deck stringers to the creek stream bed varies from approximately four to six feet (4' -6'). B. GENERAL DESIGN ELEMENTS AND MATERIALS: The Pratt Truss was one of the earlier truss designs and was developed in the United States around 1844. The truss design modified the Howe truss by putting the vertical members in compression and the diagonal members in tension. 1 During this time period, this truss type was generally used for shorter spans 2 and "probably 90 per cent of all simple spans \A/ere of this kind." 3 The particular style of truss is a half hip, meaning that there is no vertical member connected at the first joint in the top chord. This particular design is considered to be "more rigid than the full-slope type."4 The original truss was constructed of built-up sections consisting of plates rivetted to rolled channel sections. The diagonal tension members were square bars with eyes formed in the ends through which the pins were passed. The tension members are fitted with turnbuckles to allow for adjustment of the structure. The pin connections were of common use during this period, with thousands of pin­ connected bridges in service by the turn of the century. 5 This method originally was introduced around 1859 and was favored by American engineers. 6 This type of bridge was very commonly used on rural bridge crossings throughout the region. The structural members, including the truss members, the stringers, and the floor beams, are steel as are the pin-connections. These materials were commonly used in bridges of this type. The materials used in the structural modifications made to tl1e superstructure were also steel, with welded cormections. The welding is the indicator that certain elements were added to the structure subsequent to its original construction. WARREN COUNTY BRIDGE NO. 19005 (Lock Street Bridge) HAER No. NJ-86 (Page 4) The verticals and the top chord are constructed of compound sections as was typical during this era. These consist of channel sections and plates rivetted together. The diagonal tension members composed of either square or rectangular bar stock with eyebars at the ends to accommodate the pin connections. The square eyebars are fitted with turnbuckles which allow proper adjustment of the truss. The lower chord is composed of rectangular eyebars. Lateral bracing in the form of round threaded bars are connected to each floor beam. One text written in 1914 cautions that "Low truss pin-connected bridges should not be built unless extreme care is used to brace the trusses transversely11 .7 These bars provide the recommended bracing. The eastern abutment face and wingwall are composed of stone masonry. The western abutment and wingwall is also stone masonry, however concrete scour protection lines the bottom of the abutment face and the northwestern wingwall face. The stone masonry has dressed beds with quarry facing. C. BRIDGE MODIFICATIONS Modifications were made to the bridge site over the years. On the superstructure the outriggers were added to each vertical member. The date of when this construction was performed is uncertain however it is estimated to be after circa 1935. It was around this time that the practice of welded bridge connections became used regularly on moderate spans. 8 The truss was modified and reinforced with the use of welded members. Outriggers were added to each floor beam resulting in four (4) on each side of the bridge. These consist of channel members to extend the floorbeams and 11 111 sections to connect these with the upper chord. Additional bottom chord and diagonals members in the form of rectangular bars are welded to steel gusset plates which in turn are welded to the original structural members at the pin connections. Cover plates were also welded to the top chord. The deck has been reconstructed. Its original construction is unknown. The original deck stringers and deck were replaced between 1950 and 1960 by metal pans and a bituminous concrete surface course. As recent as 1985 the deck was replaced with a glue laminated wood deck and a bituminous concrete surface course. Other modifications to the structure include the adding of diagonal members to the center panel in 1980 and the reinforcing of the substructure with scour protection in the south abutment. The date of this modification is uncertain. WARREN COUNTY BRIDGE NO. 19005 (Lock Street Bridge) HAER No. NJ-86 (Page 5) The south wingwall on the eastern abutment appears to have been extended during the time of the dismantling of the canal.

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