Structure 37121 · Monona County, IA
Carries Ia 183 over Overflow Channel, 4.8 Mi. S Of SR E54.
A culvert 25 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 | Iowa |
| County | Monona |
| Location | 4.8 Mi. S Of SR E54 |
| Carries | Ia 183 |
| Crosses | Overflow Channel |
| Coordinates | 41.87035, -95.90415 |
| Material | Concrete Continuous |
| Design | Culvert |
| Total Length | 24.9 ft (7.6 m) |
| Max Span | 12.1 ft (3.7 m) |
| Deck Area | 92.7 sq m |
| Main Spans | 2 |
| Year Built | 2008 |
| Avg Daily Traffic | 580 (2022) |
| Truck Traffic | 17% |
| Lanes On Bridge | 2 |
| Last Inspection | November 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 | 000000000037121 |
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.