180th Street over Big Sioux River
Poor Condition96 years old135 vehicles/day
Location
| State | South Dakota |
| County | Hamlin |
| Location | 3n & 1.3w Of Castlewood |
| Carries | 180th Street |
| Crosses | Big Sioux River |
| Coordinates | 44.77524, -97.05305 |
Condition Ratings
| Overall Condition | Poor |
| Deck | 3 (Serious) |
| Superstructure | 4 (Poor) |
| Substructure | 4 (Poor) |
| Channel/Waterway | 5 (Fair) |
| Scour Critical | Unknown |
Physical Characteristics
| Material | Steel |
| Design | Truss - Thru |
| Total Length | 62.0 ft (18.9 m) |
| Max Span | 60.0 ft (18.3 m) |
| Deck Width | 15.7 ft (4.8 m) |
| Deck Area | 90.7 sq m |
| Main Spans | 1 |
| Year Built | 1930 (reconstructed 1970) |
Traffic
| Avg Daily Traffic | 135 (2022) |
| Truck Traffic | 2% |
| Lanes On Bridge | 1 |
Inspection & Ownership
| Last Inspection | 724 |
| Inspection Frequency | Every 12 months |
| Owner | County Highway Agency |
| Historical Significance | Bridge is eligible for the National Register |
| Structure Number | 000000029217020 |