Structure 43000100000000 · Jo Daviess County, IL
Carries US 20 over Miss River HWY Rr, In Dubuque.
Set by its lowest-rated component: Superstructure and Substructure at 6 of 9.
How ratings work5,760 ft end to end, longest span 845 ft: about 16 football fields, or 1.1 miles. 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 through arch.
| State | Illinois |
| County | Jo Daviess |
| Location | In Dubuque |
| Carries | US 20 |
| Crosses | Miss River HWY Rr |
| Coordinates | 42.49156, -90.65561 |
| Material | Steel Continuous |
| Design | Arch - Thru |
| Total Length | 5759.8 ft (1755.6 m) |
| Max Span | 845.1 ft (257.6 m) |
| Deck Width | 30.5 ft (9.3 m) |
| Deck Area | 16327.1 sq m |
| Main Spans | 3 |
| Year Built | 1943 (reconstructed 1992) |
| Avg Daily Traffic | 17,300 (2023) |
| Truck Traffic | 11% |
| Lanes On Bridge | 2 |
| Lanes Under Bridge | 2 |
| Last Inspection | October 2023 |
| Inspection Frequency | Every 24 months |
| Owner | State Highway Agency |
| Historical Significance | Bridge is on the National Register of Historic Places |
| Scour Critical | 7 — Countermeasures installed |
| Structure Number | 043000100000000 |
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.