This large through truss bridge crosses the Heart River just west of Mandan.
Originally built in 1905, the bridge first was constructed of just the truss span. Reportedly built by the McClintic-Marshall Construction Company, this is the only (presently) known span built by this firm for the Northern Pacific.
However, in 1999 a series of modern concrete beam approaches were added to the 8-panel, pin connected Pratt Through Truss. The bridge rests on concrete and steel substructures.
It is believed that these approaches were added, and the bridge raised due to flooding concerns. At this time, it also appears that the bridge received a rehabilitation.
Overall, the bridge remains in good condition. With the raise in 1999, the bridge now uses its former abutments as piers.
Historic photo of the bridge (From Structural Design: Volume I)
The author has ranked this bridge as being moderately significant, due to the lack of historic railroad truss bridges in North Dakota.
The photo above is an overview. The bridge can be accessed from the parallel road.