Irr Bia Rte 36 over White Clay Creek
Oglala Lakota County, South Dakota · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Irr Bia Rte 36 over White Clay Creek in Oglala Lakota County, South Dakota, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 8 (very good condition) on the 0-9 scale.
- It was built in 2001, making it 24 years old at the 2025 inventory.
- It carries about 7,551 vehicles a day (traffic count year 2023).
- It is one of 20 of the 35 inventoried bridges in Oglala Lakota County rated good (57.1%); 2 (5.7%) 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 July 2023, on a 24-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 → (43.02449, -102.56502)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 8 | 8 | Very good condition |
| Superstructure | 8 | 8 | Very good condition |
| Substructure | 8 | 8 | Very good condition |
Bridge details
| Structure | Continuous concrete slab |
| Length | about 107 ft |
| Location | 0.3KM E of Oglala School |
| NBI structure number | 00000000000A136 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | July 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 Oglala Lakota County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| 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 |
| Irr US018 over White Clay Ck | 2011 | 2,131 | 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.