St Onge Road over Miller Ck
Lawrence County, South Dakota · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- St Onge Road over Miller Ck in Lawrence County, South Dakota, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1950, making it 75 years old at the 2025 inventory.
- It carries about 50 vehicles a day (traffic count year 2022).
- Its listed owner is a city or municipal highway agency.
- It is one of 16 of the 136 inventoried bridges in Lawrence County rated poor (11.8%); 16 (11.8%) 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 → (44.48188, -103.72952)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 4 | Poor condition |
Bridge details
| Structure | Concrete culvert |
| Length | about 28 ft |
| Location | .3w4.5s St Onge-spearfish |
| NBI structure number | 000000041160085 |
| Condition class | Poor |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Lawrence County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Jackson Blvd over Spearfish Ck | 1966 | 12,135 | Fair |
| US014A Pine St over Whitewood Ck | 1967 | 11,370 | Fair |
| US014A over I090 | 2016 | 10,868 | Good |
| I090 W over Sandstone Dr | 1970 | 10,406 | Fair |
| I090 E over Sandstone Dr | 1970 | 10,406 | Good |
| US014A over Ck | 1994 | 9,638 | Good |
All bridges nearby: Lawrence County, SD bridge conditions · every bridge in Lawrence County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.