Structure 17770 · Cass County, IA
Carries Ia 83 over Compton Creek, 0.1 Mi. W Of Jct. SR M56.
A culvert 20 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 | Cass |
| Location | 0.1 Mi. W Of Jct. SR M56 |
| Carries | Ia 83 |
| Crosses | Compton Creek |
| Coordinates | 41.44675, -95.11436 |
| Material | Concrete Continuous |
| Design | Culvert |
| Total Length | 20.0 ft (6.1 m) |
| Max Span | 9.8 ft (3 m) |
| Deck Area | 67.1 sq m |
| Main Spans | 2 |
| Year Built | 1936 (reconstructed 1991) |
| Avg Daily Traffic | 760 (2022) |
| Truck Traffic | 13% |
| Lanes On Bridge | 2 |
| Last Inspection | March 2024 |
| Inspection Frequency | Every 24 months |
| Owner | State Highway Agency |
| Historical Significance | Bridge is not eligible for the National Register |
| Scour Critical | 7 — Countermeasures installed |
| Structure Number | 000000000017770 |
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.