Structure 17090 · Carroll County, IA
Carries US 30 over Ditch #77, 1.1 Mi. E. Of Jct. US 71.
Set by its lowest-rated component: Deck and Superstructure at 6 of 9.
How ratings work25 ft end to end. 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 or the layout of the shorter spans, so those are drawn as typical for a slab bridge.
| State | Iowa |
| County | Carroll |
| Location | 1.1 Mi. E. Of Jct. US 71 |
| Carries | US 30 |
| Crosses | Ditch #77 |
| Coordinates | 42.06401, -94.85939 |
| Material | Concrete |
| Design | Slab |
| Total Length | 24.9 ft (7.6 m) |
| Max Span | 24.9 ft (7.6 m) |
| Deck Width | 142.4 ft (43.4 m) |
| Deck Area | 329.8 sq m |
| Main Spans | 1 |
| Year Built | 1919 (reconstructed 1974) |
| Avg Daily Traffic | 13,000 (2022) |
| Truck Traffic | 8% |
| Lanes On Bridge | 4 |
| Last Inspection | February 2023 |
| Inspection Frequency | Every 24 months |
| Owner | State Highway Agency |
| Historical Significance | Historical significance is not determined |
| Scour Critical | 8 — Stable, low risk |
| Structure Number | 000000000017090 |
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.