Old Highway 85 over Hay Ck
Butte County, South Dakota · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Old Highway 85 over Hay Ck in Butte County, South Dakota, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1932, making it 93 years old at the 2025 inventory.
- It carries about 21 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 76 of the 142 inventoried bridges in Butte County rated fair (53.5%); 20 (14.1%) are rated poor.
- 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 → (45.19866, -103.5683)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 6 | Satisfactory condition |
Bridge details
| Structure | Concrete culvert |
| Length | about 20 ft |
| Location | 6N 14.7W of Hoover |
| NBI structure number | 000000010239010 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Butte County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US085 over Hay Ck | 1963 | 15,432 | Fair |
| US085 over Belle Fourche Rv | 1958 | 10,476 | Fair |
| SD034 over Willow Ck | 1939 | 3,961 | Fair |
| SD034 over Redwater Rv | 1992 | 3,547 | Fair |
| SD034 over Redwater Canal | 1964 | 3,547 | Good |
| SD034 over False Bottom Ck | 1992 | 3,547 | Fair |
All bridges nearby: Butte County, SD bridge conditions · every bridge in Butte County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.