Irr US012 over Dry Run Ck
Corson County, South Dakota · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Irr US012 over Dry Run Ck in Corson 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 1964, making it 61 years old at the 2025 inventory.
- It carries about 391 vehicles a day (traffic count year 2024).
- Its listed owner is the state highway agency.
- It is one of 26 of the 49 inventoried bridges in Corson County rated fair (53.1%); 4 (8.2%) 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 → (45.81861, -100.83292)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous concrete culvert |
| Length | about 20 ft |
| Location | 0.7 W Jct Sd 63 |
| NBI structure number | 000000016574090 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Corson County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Irr US012 over Claymore Ck | 1958 | 1,378 | Poor |
| Irr US012 over Deep Bank Ck | 1965 | 1,091 | Fair |
| Irr US012 over Br Snake Ck | 1965 | 1,091 | Fair |
| Irr US012 over Snake Ck | 1966 | 1,091 | Fair |
| Irr SD020 over Ck | 2000 | 956 | Good |
| Irr SD063 over Oak Ck | 1980 | 864 | Fair |
All bridges nearby: Corson County, SD bridge conditions · every bridge in Corson County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.