257 St over Cottonwood Ck
Tripp County, South Dakota · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 257 St over Cottonwood Ck in Tripp 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 2006, making it 19 years old at the 2025 inventory.
- It carries about 55 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 38 of the 89 inventoried bridges in Tripp County rated fair (42.7%); 22 (24.7%) 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 June 2023, 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 → (43.6737, -100.09656)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 8 | 8 | Very good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Prestressed concrete tee beam |
| Length | about 100 ft |
| Location | 0.6W & 15.9N Witten |
| NBI structure number | 000000062072071 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | June 2023 |
| 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 Tripp County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US018 over Dog Ear Ck | 1965 | 3,553 | Fair |
| US018 Ser Rd over Ck | 1965 | 2,820 | Fair |
| US018 over Sand Ck | 1973 | 2,052 | Fair |
| US018 over Ck | 1973 | 1,803 | Fair |
| US018 over Cottonwood Ck | 1965 | 1,746 | Fair |
| US018 over Big Hollow Ck | 1965 | 1,746 | Good |
All bridges nearby: Tripp County, SD bridge conditions · every bridge in Tripp County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.