Wilbur Rd. / River RaisinCounty: Washtenaw
City/Township: Bridgewater Twp.
Location: Wilbur Rd. / River Raisin
Year Built: 1953 About this Bridge: Located in a wooded area southwest of Manchester, this bridge carries a one-lane unpaved road over the Raisin River. Concrete footings from a previous span appear on either side of the bridges south abutment. The “Bailey”-type pony truss bridge was developed in 1941 by Donald Coleman Bailey, chief engineer of the British Experimental Bridging Establishment, and was adopted by the United States’ military in the same year. Based upon a system of steel panel trusses edging a roadway carried by steel I-beam stringers, the design proved remarkably versatile and was employed during World War II in both the European and Pacific theaters. The Bailey proved particularly appealing because it could easily be altered in place to handle a variety of vehicle weights and sizes. The strength of the structure was varied by vertically stacking the panel trusses and/or combining them side-by-side. Usually the bridge was at least partially assembled on shore and then “launched” across the gap. The U.S. military, which used the Bailey for spans up to 180 feet, boasted that one platoon of engineers could erect a 100-foot, double truss, single-story bridge in about five hours. After the war, the military offered Bailey bridges for sale through the War Assets Administration. Ingham County Purchased at least three for use a temporary crossing during its bridge projects. The present Washtenaw County bridge is a double-truss, single-story Bailey structure reportedly constructed in 1953. No archival information could be located indicating whether any war-surplus materials were used. The bridge received a new timber deck and steel stringers in 1984. Because the repair project apparently did not alter the trusses, this bridge remains a good example of a relatively rare span type.