Structure 409 · Arenac County, MI
Carries I-75 Nb|us-23 NB over Sunsmith Drain, 0.5 Mi N Of Worth RD.
A culvert 22 ft across with 2 openings. Lengths are drawn to scale; at this length a semi-truck would be a speck. Each part is colored by its latest inspection rating. The inventory records lengths but not heights, so those are drawn as typical for a culvert.
| State | Michigan |
| County | Arenac |
| Location | 0.5 Mi N Of Worth RD |
| Carries | I-75 Nb|us-23 NB |
| Crosses | Sunsmith Drain |
| Coordinates | 43.93293, -84.01760 |
| Material | Concrete |
| Design | Culvert |
| Total Length | 22.3 ft (6.8 m) |
| Max Span | 10.5 ft (3.2 m) |
| Deck Area | 182.2 sq m |
| Main Spans | 2 |
| Year Built | 1968 |
| Avg Daily Traffic | 27,470 (2007) |
| Truck Traffic | 9% |
| Lanes On Bridge | 2 |
| Last Inspection | April 2024 |
| Inspection Frequency | Every 24 months |
| Owner | State Highway Agency |
| Historical Significance | Bridge is not eligible for the National Register |
| Scour Critical | 8 — Stable, low risk |
| Structure Number | 000000000000409 |
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.