Structure 2000600000000 · Alexander County, IL
Carries US 51 over Ohio River, 1 Mi S Cairo.
Set by its lowest-rated component: Deck and Superstructure and Substructure at 5 of 9.
How ratings work5,865 ft end to end, longest span 800 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 truss.
| State | Illinois |
| County | Alexander |
| Location | 1 Mi S Cairo |
| Carries | US 51 |
| Crosses | Ohio River |
| Coordinates | 36.98883, -89.15116 |
| Material | Steel Continuous |
| Design | Truss - Thru |
| Total Length | 5865.2 ft (1787.7 m) |
| Max Span | 799.9 ft (243.8 m) |
| Deck Width | 25.9 ft (7.9 m) |
| Deck Area | 14122.8 sq m |
| Main Spans | 5 |
| Year Built | 1937 (reconstructed 1979) |
| Avg Daily Traffic | 5,700 (2023) |
| Truck Traffic | 25% |
| Lanes On Bridge | 2 |
| Last Inspection | August 2024 |
| Inspection Frequency | Every 12 months |
| Owner | State Highway Agency |
| Historical Significance | Bridge is not eligible for the National Register |
| Scour Critical | 5 — Stable for scour |
| Structure Number | 002000600000000 |
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.