470TH Avenue over Big Sioux Rv
Brookings County, South Dakota · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 470TH Avenue over Big Sioux Rv in Brookings County, South Dakota, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- It was built in 1930, making it 95 years old at the 2025 inventory.
- It carries about 1,330 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- 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 → (44.22107, -96.80944)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 4 | Poor condition |
| Superstructure | 5 | Fair condition |
| Substructure | 5 | Fair condition |
Bridge details
| Structure | Steel through truss |
| Length | about 77 ft |
| Location | 0.6W & 4.1S Brookings |
| NBI structure number | 000000006159221 |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
All bridges nearby: Brookings County, SD bridge conditions · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.