Ahnapee State Trail - Kewaunee River Bridge (East)

Located in a swampy area on the west side of Kewaunee, this unique deck plate girder swing bridge carries the former Green Bay & Western Railroad Kewaunee Car Ferry Line over the Kewaunee River. In 1892, a car ferry was constructed across Lake Michigan to connect to Ludington, Michigan and Frankfort, Michigan. At Ludington, the ferry connected to the Pere Marquette Railway, later the Chesapeake & Ohio Railroad; and at Frankfort, the ferry connected to the Ann Arbor Railroad. To facilitate the ferry service, two lines were constructed into Kewaunee, one on either side of the Kewaunee River. The southern line was constructed to serve industry in Kewaunee, while the northern line connected directly to the ferry slip. The first bridge at this location was likely a timber pile trestle, constructed when the ferry slip line was first built in 1892. Between 1900 and 1910, the KGB&W under the direction of parent GB&W invested significant capital into this line, replacing many of the timber bridges with steel and concrete structures. In the summer of 1905, the present bridge was constructed at this location. Currently, the bridge consists of an 80-foot center bearing deck plate girder swing span, approached by timber pile trestle spans on either end. While the bridge was initially constructed entirely on timber piles, the piers supporting the swing span were later replaced with steel pile structures. The deck plate girder span uses a typical design for the era, with heavy girders and an open deck. Unlike many swing spans, the bridge uses a center bearing design, where wheels are attached directly to the bottom of superstructure, which rotate on a track placed on a center pier. Rim-bearing designs, with a steel drum rotating on a roller nest, were more common and better developed for railroad use. The use of a center bearing swing span was possibly required due to the limited clearance beneath the structure.

While it is unclear which contractor fabricated the main span, the GB&W used the Wisconsin Bridge & Iron Company for most steel spans. It is likely that this contractor also constructed this bridge. The timber components of the bridge were constructed by railroad company forces. Deck plate girder spans were commonly used by railroads, as they were durable and easy to construct. These types of spans were also suitable for short swing spans over small navigable waterways. Since the initial construction, the bridge has seen some alterations. These alterations include the replacement of some original timber piers with steel pile structures, likely completed in the later half of the 20th Century. It also appears that the bridge is no longer capable of opening for river traffic, and most of the related machinery has been removed. This includes the gears and end roller bearings. After the car ferry at Kewaunee was discontinued in 1990, the line was abandoned and acquired for trail use. Currently, the bridge carries the Ahnapee State Trail, and a deck and handrails have been added to the bridge. Overall, the bridge appears to be in fair condition, with no significant deterioration noted. The author has ranked this bridge as being moderately significant, as it is an excellent example of a relatively unusual center-bearing swing span.