485TH Avenue over Flandreau Creek
Moody County, South Dakota · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 485TH Avenue over Flandreau Creek in Moody County, South Dakota, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1958, making it 67 years old at the 2025 inventory.
- It carries about 45 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 42 of the 88 inventoried bridges in Moody County rated fair (47.7%); 18 (20.5%) are rated poor.
- Its traffic status in the 2025 inventory is posted for load (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated August 2024, on a 24-month routine inspection cycle.
- A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (44.05426, -96.50607)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 5 | 5 | Fair condition |
Bridge details
| Structure | Continuous concrete slab |
| Length | about 163 ft |
| Location | 4E & 0.2N of Flandreau |
| NBI structure number | 000000051190098 |
| Condition class | Fair |
| Traffic status (item 41) | Posted for load |
| Last inspection (item 90) | August 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Moody County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I029 S over 243 St | 1963 | 10,190 | Fair |
| I029 N over 243 St | 1963 | 10,190 | Fair |
| I029 S over 238 St | 1963 | 10,030 | Fair |
| I029 S over Bachelor Ck | 1964 | 10,030 | Fair |
| I029 N over 238 St | 1963 | 10,030 | Fair |
| I029 N over Bachelor Ck | 1964 | 10,030 | Fair |
All bridges nearby: Moody County, SD bridge conditions · every bridge in Moody County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.