This by the way appears to have been a nationally significant bridge. It is a Parker truss (polygonal top chord, not curved) but the members and chord design is strongly reminiscent of an 1870s bowstring truss from the overall arch-like shape of the truss to the composition of the beams such as the plate-like bottom chord.
This bridge was destroyed in the flooding of May 2010. Parts of the bridge are still laying across the river. The next time I go out that way I will make sure to take some pictures.