Radar Hill Road over Boxelder Ck
Pennington County, South Dakota · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Radar Hill Road over Boxelder Ck in Pennington County, South Dakota, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1989, making it 36 years old at the 2025 inventory.
- It carries about 966 vehicles a day (traffic count year 2022).
- Its listed owner is a town or township highway agency.
- It is one of 206 of the 348 inventoried bridges in Pennington County rated fair (59.2%); 21 (6.0%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (fair), but component ratings moved: substructure 7 to 6.
- Its most recent inspection on record is dated April 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 → (44.10938, -103.09083)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 6 | Satisfactory condition |
Bridge details
| Structure | Prestressed concrete tee beam |
| Length | about 80 ft |
| Location | 1.0W 0.3S Box Elder |
| NBI structure number | 000000052480282 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | April 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 Pennington County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I090 over Boxelder Ck | 1994 | 26,980 | Good |
| Cambell St over Ck | 1964 | 23,179 | Fair |
| SD079NF over St Joseph St Rcp&e RR | 1964 | 23,179 | Fair |
| Cambell St over Rapid Ck | 1967 | 21,415 | Fair |
| West Main St. over Rapid Ck | 1975 | 20,745 | Good |
| SD231 over Rapid Ck | 1974 | 20,057 | Fair |
All bridges nearby: Pennington County, SD bridge conditions · every bridge in Pennington County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.