Monocacy Watershed Bridges, Maryland
The Monocacy River and its tributaries in Frederick County, Maryland, are a treasure trove of late 19th and early 20th century steel-through truss and pony truss bridges. Particularly well-represented is the York Bridge Company, with six through-truss bridges constructed from 1890 to 1914. There are also bridges from the Wrought Iron Bridge Company of Canton, Ohio, as well as bridges by the Penn Bridge Company, Pittsburg Bridge Company, and King Bridge Company.
One of the highlights is the Four Points Bridge, by the Wrought Iron Bridge Company. Instead of the construction date that is usually displayed on early bridges, the date plaque on this bridge presents the date of November 21, 1876, which was the date that the truss type was patented. The bridge was washed off of the abutments by a flood in 1996, but was re-constructed.
The Mumma Ford Bridge, constructed by the York Bridge Company in 1911, is the longest of the bridges, having two spans. However, each span was later reinforced with a steel arch, giving the bridge an unusual combination of an arch-truss appearance.
The Poffenberger Road Bridge is an excellent example of how the historical documentation on these bridges can become jumbled, confusing interested bridgespotters. This does not have a builder plaque attached. The National Register of Historic Places Inventory Nomination Form states that it is a Wrought Iron Bridge Company bridge, but without any qualification or explanation. This information was later adopted by multiple sources, including bridgehunter.com, Wikipedia, and the “official” 2002 book on historic bridges of Maryland by Legler and Highsmith. However, historicbridges.org noted that the portal ornamentation of the Poffenberger Road Bridge was distinctive, consisting of an intricate, hand-cut geometric design that exactly matches the portal on the Bauer Road Bridge in the Calhoun County Historic Bridge Park in Michigan. Because the Bauer Road Bridge has legible cast-iron buttons inscribed with “PENN” on its lattice joints, the Poffenberger Road Bridge can confidently be attributed to the Penn Bridge Company. This means that all of the historic documentation attributing this bridge to the Wrought Iron Bridge Company is incorrect.