Irr SD020 over Ck
Dewey County, South Dakota · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Irr SD020 over Ck in Dewey County, South Dakota, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 8 (very good condition) on the 0-9 scale.
- It was built in 1997, making it 28 years old at the 2025 inventory.
- It carries about 890 vehicles a day (traffic count year 2024).
- Its listed owner is the state highway agency.
- It is one of 15 of the 27 inventoried bridges in Dewey County rated good (55.6%); 4 (14.8%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated July 2023, on a 48-month routine inspection cycle.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (45.42917, -101.15512)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Culvert | 8 | 8 | Very good condition |
Bridge details
| Structure | Continuous concrete culvert |
| Length | about 26 ft |
| Location | 3.3 E Jct Sd 63 |
| NBI structure number | 000000021174030 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | July 2023 |
| Inspection interval (item 91) | 48 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 Dewey County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Irr US212 over Little Bear Ck | 2023 | 1,291 | Good |
| Irr SD020 over Ck | 1997 | 890 | Good |
| Irr SD063 over Moreau Rv | 1971 | 717 | Fair |
| Irr US212 over Virgin Ck | 1990 | 601 | Good |
| Irr US212 over Virgin Ck | 1988 | 601 | Good |
| Irr SD020 over Little Moreau Rv | 1993 | 598 | Good |
All bridges nearby: Dewey County, SD bridge conditions · every bridge in Dewey County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.