Smithwick Road over White River
Oglala Lakota County, South Dakota · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Smithwick Road over White River in Oglala Lakota County, South Dakota, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 2 (critical condition) on the 0-9 scale.
- It was built in 1935, making it 90 years old at the 2025 inventory.
- It carries about 10 vehicles a day (traffic count year 2020).
- It is one of 2 of the 35 inventoried bridges in Oglala Lakota County rated poor (5.7%); 2 (5.7%) 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 → (43.25486, -102.82742)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 3 | Serious condition |
| Superstructure | 2 | Critical condition |
| Substructure | 2 | Critical condition |
Bridge details
| Structure | Steel through truss |
| Length | about 195 ft |
| Location | .75 Km NE of Bia Rte 41 |
| NBI structure number | 00000000000A154 |
| Condition class | Poor |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Oglala Lakota County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Irr Bia Rte 36 over White Clay Creek | 2001 | 7,551 | Good |
| Irr US018 over Wolf Ck | 2006 | 5,154 | Fair |
| Irr US018 over Ck | 2016 | 3,597 | Good |
| Irr US018 over Ck | 2011 | 3,274 | Good |
| Irr US018 over Cheyenne Ck | 2020 | 3,274 | Good |
| Irr Bia Rte 27 over White River | 1985 | 2,368 | Fair |
All bridges nearby: Oglala Lakota County, SD bridge conditions · every bridge in Oglala Lakota County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.