476TH Avenue over Big Slough Creek
Roberts County, South Dakota · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 476TH Avenue over Big Slough Creek in Roberts County, South Dakota, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1930 and reconstructed in 1970, making it 95 years old at the 2025 inventory.
- It carries about 22 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 40 of the 158 inventoried bridges in Roberts County rated poor (25.3%); 40 (25.3%) are rated poor.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (45.88427, -96.66778)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 6 | Satisfactory condition |
| Superstructure | 4 | Poor condition |
| Substructure | 4 | Poor condition |
Bridge details
| Structure | Concrete channel beam |
| Length | about 23 ft |
| Location | 3E & 1.4N of Rosholt |
| NBI structure number | 000000055270036 |
| Condition class | Poor |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Roberts County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Irr SD010 over Ck | 2019 | 7,072 | Good |
| Irr SD010 over Ck | 1979 | 6,275 | Fair |
| 458TH Avenue over Creek | 1941 | 5,850 | Fair |
| 458TH Avenue over Creek | 1941 | 5,850 | Fair |
| 459TH Avenue over Creek | 1941 | 5,850 | Good |
| Irr I029 over Big Spring Ck | 1978 | 5,340 | Fair |
All bridges nearby: Roberts County, SD bridge conditions · every bridge in Roberts County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.