Il 83 171 over Cal Sag Extension
Fair Condition91 years old20,500 vehicles/day
Location
| State | Illinois |
| County | Cook |
| Location | 0.2 M S Il 171 |
| Carries | Il 83 171 |
| Crosses | Cal Sag Extension |
| Coordinates | 41.69557, -87.93624 |
Condition Ratings
| Overall Condition | Fair |
| Deck | 7 (Good) |
| Superstructure | 7 (Good) |
| Substructure | 6 (Satisfactory) |
| Channel/Waterway | 8 (Very Good) |
| Scour Critical | 8 — Stable, low risk |
Physical Characteristics
| Material | Steel Continuous |
| Design | Stringer/Multi-beam |
| Total Length | 502.3 ft (153.1 m) |
| Max Span | 50.2 ft (15.3 m) |
| Deck Width | 57.1 ft (17.4 m) |
| Deck Area | 2663.9 sq m |
| Main Spans | 10 |
| Year Built | 1935 (reconstructed 1997) |
Traffic
| Avg Daily Traffic | 20,500 (2023) |
| Truck Traffic | 4% |
| Lanes On Bridge | 4 |
Inspection & Ownership
| Last Inspection | 623 |
| Inspection Frequency | Every 24 months |
| Owner | State Highway Agency |
| Historical Significance | Bridge is not eligible for the National Register |
| Structure Number | 016102200000000 |