| Key Facts |
| Bridge Name | Facility Carried / Feature Intersected | Location | Structure Type | Construction Date / Builder or Contractor |
| Marengo Bridge
23 Mile Road Bridge | 23 Mile Road Over Kalamazoo River | Marengo: Calhoun County, Michigan | Concrete 60 Foot Plan Curved Chord Through Girder, Stationary | 1922 By: Mead Brothers |
| Technical Facts |
| Structure Length | Roadway Width | Main Spans | Approach Spans |
| 60 Feet (18.2 Meters) | 20 Feet (6.1 Meters) | 1 | None |
This concrete camelback bridge, also known as a curved-chord through girder, appears to be the last of its kind in Calhoun County. The structure was built in 1922, and as a result is a very old example of this structure type.
The treatment of concrete camelback bridges like this one has been no better than the treatment that truss bridges get. They have survived because they were built later than most truss bridges and they were significantly overbuilt which has helped them have a long life. The bridges of this type that have been demolished are usually because these bridges are not quite wide enough to comfortably support two lanes. The preservation of these unique bridges, which were designed by Michigan and built in no other state, is important to honor and remember Michigan's innovation in the development of effective transportation systems. In addition, preservation allows these visually pleasing structure to continue to add to the desirability of the roadway and surrounding area.
Information and Findings From MDOT
Plans for the 23 Mile Road Bridge were prepared by the state highway department in January 1922. The bridge was subsequently built by Calhoun County as a state reward bridge. The contractor, Mead Brothers of Battle Creek, Michigan, had to dismantle the superstructure of the previous bridge, probably a steel truss, before erecting the new concrete span. Construction cost of the new bridge totaled $10,353. |
