Structure 91005000001069 · Mackinac County, MI
Carries Usfs RTE 3445 over Carp River, 0.1 Mi W H63.
Set by its lowest-rated component: Deck and Substructure at 4 of 9.
How ratings work91 ft end to end, longest span 19 ft. Lengths and the car on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.
| State | Michigan |
| County | Mackinac |
| Location | 0.1 Mi W H63 |
| Carries | Usfs RTE 3445 |
| Crosses | Carp River |
| Coordinates | 46.03386, -84.72014 |
| Material | Steel |
| Design | Stringer/Multi-beam |
| Total Length | 90.6 ft (27.6 m) |
| Max Span | 19.0 ft (5.8 m) |
| Deck Width | 17.7 ft (5.4 m) |
| Deck Area | 149.0 sq m |
| Main Spans | 5 |
| Year Built | 1962 |
| Avg Daily Traffic | 15 (1998) |
| Lanes On Bridge | 1 |
| Last Inspection | October 2024 |
| Inspection Frequency | Every 12 months |
| Owner | U.S. Forest Service |
| Historical Significance | Historical significance is not determined |
| Scour Critical | 4 — Foundations need monitoring |
| Structure Number | 091005000001069 |
Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."
A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.