Bridge conditions in Lemhi County, Idaho
114 inventoried bridges · 9 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
9 of the 114 bridges the federal inventory lists in Lemhi County are rated poor; the rest split 65 good and 40 fair.
- 9 of the 114 bridges in Lemhi County, Idaho, are rated in poor condition (7.9%) in the 2025 National Bridge Inventory, as of .
- 65 bridges (57.0%) are rated good and 40 (35.1%) fair.
- The median Lemhi County bridge was built in 1992.
- The busiest poor-rated bridge is US 93 over Salmon River;salmon Br. (built 1926), carrying about 7,300 vehicles a day.
Good 57.0% · Fair 35.1% · Poor 7.9% of 114 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 93 over Salmon River;salmon Br. | 1926 | 7,300 | Poor |
| Salmon River Road over Pine Creek | 2012 | 350 | Poor |
| N. St. Charles over Lemhi River | 1948 | 310 | Poor |
| No Data Entered over Boulder Creek | 1966 | 200 | Poor |
| No Data Entered over Panther Creek | 1980 | 200 | Poor |
| Viola Lane over Lemhi River(bagley Br) | 1991 | 50 | Poor |
| No Data Entered over Yellowjacket Creek | 1962 | 50 | Poor |
| Moccasin-napias Rd over Napias Creek | 1953 | 25 | Poor |
| Road over Bear Valley Creek | 1960 | 10 | Poor |
Busiest bridges in the 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 |
| SH 28 over Lemhi River | 2001 | 1,600 | Good |
| SH 28 over Lemhi River | 2018 | 1,600 | Good |
| Williams Creek Rd over Salmon River; Shoup Br | 2018 | 1,200 | Good |
| US 93 over N.fk.salmon River | 1955 | 1,100 | Fair |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of Idaho: Idaho bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.