SH 78 over Birch Creek
Owyhee County, Idaho · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- SH 78 over Birch Creek in Owyhee County, Idaho, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1954, making it 71 years old at the 2025 inventory.
- It carries about 580 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 29 of the 49 inventoried bridges in Owyhee County rated fair (59.2%); 4 (8.2%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (fair), but component ratings moved: deck 6 to 7, superstructure 6 to 7.
- Its most recent inspection on record is dated August 2024, 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 → (43.02567, -116.18897)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 7 | Good condition |
| Superstructure | 6 | 7 | Good condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Concrete frame |
| Length | about 27 ft |
| Location | 24.8 E. Murphy |
| NBI structure number | 000000000015285 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2024 |
| 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 Idaho department of transportation.
Busiest bridges in Owyhee County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 95 over Snake River;homedale Br. | 1969 | 11,000 | Fair |
| SH 55 over Snake River (marsing Br) | 2020 | 7,500 | Fair |
| US 95 over B Line Canal | 1982 | 3,600 | Good |
| US 95 over Jump Creek | 1982 | 3,200 | Good |
| SH 19 over Succor Creek | 2017 | 2,500 | Good |
| SH 45 over Snake R.(walters Ferry) | 1972 | 1,900 | Fair |
All bridges nearby: Owyhee County, ID bridge conditions · every bridge in Owyhee County · Idaho bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.