A drive along Burnt Mill Road in Lurgan Township in Franklin County winds around scenic county farmland crossing the Conodoguinet Creek where a monument to Pennsylvania’s industrial past, the Burnt Mill Road Bridge, has stood for the past 136 years.
The Burnt Mill Road metal truss bridge (PA-SHARE Resource #2004RE06914) is a 105 foot long and 14 foot 6 inch wide single-span Pratt through truss that was built in 1885. The bridge’s pinned connections and wrought iron members are evidence of its early construction.
The bridge was built by the Pittsburgh Bridge Company, an important Pennsylvania bridge builder who had connections to Franklin County through Thomas Nelson of Chambersburg. Nelson, along with Andrew Buchanan, became agents who sold bridges for the Pittsburgh Bridge Company and were responsible for assembling the bridges on site for the company. Many bridges in the state have plaques with Nelson and Buchanan named as the bridge engineers. Thomas Nelson also served as president of the Pittsburgh Bridge Company from 1896 to 1900.
In those early days, Pennsylvania was the heart of the iron and steel industry and many bridge manufactures located to Pennsylvania to be near the raw materials needed to make metal truss bridges. Iron and steel manufactures often stamped their metal with a brand during production. Many of these brands can be seen on metal truss bridge members today. Members of the Burnt Mill Road Bridge are marked with the Carnegie Steel Company brand.
The Carnegie Steel Company, founded by Andrew Carnegie and associates in Pittsburgh, provided the metal used in the members of the Burnt Mill Road Bridge. The Burnt Mill Road Bridge is a true Pennsylvania bridge from its raw material to its construction!
Character defining feature of the Burnt Mill Road bridge include: the wrought iron truss material, the Pratt thru truss form, the pinned connections, the structural members to include the top and bottom chords, verticals and diagonal members, sway bracing, features of the portal, and the builder plaques. Note the built-up floorbeam members on the Burnt Mill Road Bridge, another feature seen on early metal truss bridges. Before the technology arrived allowing a single large, rolled metal beam, smaller steel elements were riveted together to form larger and stronger beams.
The Burnt Mill Road Bridge also exhibits two rare features. On the top chord there is a second pin connection that connects the vertical member to a gusset plate that is riveted to the top chord. On the bottom chord, the connections are framed into the floorbeams instead of using a U-bolt hanger system which was the common connection method of the time. Due to these features the bridge was characterized as an Exceptional Preservation Priority in the state’s Metal Truss Bridge Management Plan.
When the Pennsylvania Department of Transportation and the PA SHPO met with Franklin County Officials to discuss the Metal Truss Bridge Management Plan in 2017 and again in 2020, a decision was made to add the Burnt Mill Road Bridge to the bridge marketing list.
While a set deadline has not been determined for the removal of the bridge, the local owners recognize that the bridge will likely need to be removed in the future and want to market the bridge in advance of a removal project to give this early bridge as much time as possible to find a new owner and location.
The Burnt Mill Road bridge has all the details of an early Pennsylvania-built metal truss bridge as well as unique construction details that aren’t found on other bridges. This bridge could be a monument in your trail or park system, bringing a tangible part of Pennsylvania’s iron and steel industrial history to your site.
Burnt Mill Road Bridge Quick Facts:
Year Built: 1885
Type: Pratt Thru
Number of Spans: 1
Length: 105 feet
Width: 14 feet 6 inches
Vertical Clearance: 13 feet 5 inches
Builder: Pittsburgh Bridge Company, Pittsburgh, PA
Location: Lurgan Township, Franklin Township
Carries: Burnt Mill Road over Conodoguinet creek
If you or your organization is interested in assuming ownership of the Burnt Mill Road Bridge or finding out more about the steps to relocate the structure, please contact Tyra Guyton of the Pennsylvania State Historic Preservation Office at tyguyton@pa.gov or (717) 346-0617 Veronica Martin of the Pennsylvania Department of Transportation at vermartin@pa.gov or at (717) 705-1482.
