Structure 16031500000000 · Cook County, IL
Carries Harlem AVE NB Ill over San & Ship Canal, 0.1 M N I55.
Set by its lowest-rated component: Superstructure and Substructure at 4 of 9.
How ratings work456 ft end to end: about 6 semi-trucks nose to tail. Lengths and the semi-truck on the deck are drawn to the same scale. 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 bascule bridge (drawn closed).
| State | Illinois |
| County | Cook |
| Location | 0.1 M N I55 |
| Carries | Harlem AVE NB Ill |
| Crosses | San & Ship Canal |
| Coordinates | 41.80138, -87.80218 |
| Material | Steel |
| Design | Movable - Bascule |
| Total Length | 456.4 ft (139.1 m) |
| Max Span | 224.1 ft (68.3 m) |
| Deck Width | 72.8 ft (22.2 m) |
| Deck Area | 3088.0 sq m |
| Main Spans | 1 |
| Year Built | 1931 (reconstructed 1990) |
| Avg Daily Traffic | 35,500 (2023) |
| Truck Traffic | 5% |
| Lanes On Bridge | 3 |
| Last Inspection | August 2024 |
| Inspection Frequency | Every 12 months |
| Owner | State Highway Agency |
| Historical Significance | Bridge is possibly eligible (requires evaluation) |
| Scour Critical | 8 — Stable, low risk |
| Structure Number | 016031500000000 |
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.