Fs Route No. 456A over N.f. St Joe River
Shoshone County, Idaho · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Fs Route No. 456A over N.f. St Joe River in Shoshone County, Idaho, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1935, making it 90 years old at the 2025 inventory.
- It carries about 50 vehicles a day.
- It is one of 26 of the 261 inventoried bridges in Shoshone County rated poor (10.0%); 26 (10.0%) 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 August 2022, on a 12-month routine inspection cycle.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- 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 → (47.33692, -115.75184)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 5 | Fair condition |
| Superstructure | 4 | 4 | Poor condition |
| Substructure | 4 | 4 | Poor condition |
Bridge details
| Structure | Steel through truss |
| Length | about 119 ft |
| Location | Loop Creek |
| NBI structure number | 010402000001056 |
| Condition class | Poor |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2022 |
| Inspection interval (item 91) | 12 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Idaho department of transportation.
Busiest bridges in Shoshone County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I 90 over Stc 5766;SILVERTON Ic | 1978 | 11,000 | Fair |
| I 90 EB & WB over S.fk.cda R;fr.rd. | 1978 | 11,000 | Fair |
| I 90 over S.fk.coeur Dalene River | 1987 | 11,000 | Fair |
| I 90 Ebl & Wbl over Crossroad Bd;w.wallace I | 1987 | 11,000 | Fair |
| I 90 over I 90B;CANYON CR | 1991 | 11,000 | Fair |
| I 90 Spur over Canyon Creek | 1940 | 10,500 | Fair |
All bridges nearby: Shoshone County, ID bridge conditions · every bridge in Shoshone County · Idaho bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.