US 93 over N. Fork Salmon River
Lemhi County, Idaho · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US 93 over N. Fork Salmon River in Lemhi County, Idaho, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 8 (very good condition) on the 0-9 scale.
- It was built in 1997, making it 28 years old at the 2025 inventory.
- It carries about 670 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 65 of the 114 inventoried bridges in Lemhi County rated good (57.0%); 9 (7.9%) 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 2024, on a 48-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 → (45.59361, -113.96306)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Culvert | 8 | 8 | Very good condition |
Bridge details
| Structure | Steel culvert |
| Length | about 22 ft |
| Location | 15.1 N. North Fork |
| NBI structure number | 000000000033340 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2024 |
| Inspection interval (item 91) | 48 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 Lemhi County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 93 over Salmon River;salmon Br. | 1926 | 7,300 | Poor |
| US 93 over Salmon River;carmen Br. | 1970 | 2,100 | Fair |
| US 93 over Carmen Creek | 1931 | 2,100 | Fair |
| US 93 over Tower Creek | 1931 | 2,100 | Fair |
| SH 28 over Lemhi River | 2001 | 1,700 | Good |
| SH 28 over Lemhi River | 2001 | 1,700 | Good |
All bridges nearby: Lemhi County, ID bridge conditions · every bridge in Lemhi County · Idaho bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.