Year constructed: c1895
Bridge type: Pin-and Rigid-Connected Kingpost Pony Truss
National Register of Historic Places status: Bridge is un-evaluated in its current location
Length: 36 feet
Width: 16 feet
Spans: 1
FHWA: 347800
Jurisdiction: Winneshiek County Conservation
Location: Trout Run Trail in Decorah, Section 28, T98N-R08W (Decorah Township)
Details
This short-span crossing of Ten Mile Creek is located some five miles northwest of Decorah in central Winneshiek County. County records do not refer specifically to this kingpost pony truss, but it appears to have been built circa 1895, probably by the R.D. Wheaton Bridge Company of Chicago, which supplied several kingpost trusses to the county at that time. Consisting of a kingpost pony truss with rigid-connected upper chords and pinned lowers, the structure is supported by stone abutments. Since its completion, the Ten Mile Creek Bridge has continued to carry intermittent traffic in its picturesque setting, while retaining an exceptional degree of structural integrity.
With its roots extending to the Middle Ages, the kingpost pony truss was the most rudimentary truss type. Numerous kingposts were built on Iowa's early roads in the late 19th and early 20th centuries, executed first as timber/iron combination structures and later in all-metal configurations. The Kingpost as a structural type was generally limited to relatively short-span applications, however, and as steel beam bridges received widespread acceptance after the turn of the century, erection of kingpost trusses declined rapidly. This bridge in Winneshiek County is a well-preserved example of this mainstay structural type [adapted from Crow-Dolby and Fraser 1992].