Bridge conditions in Butte County, Idaho
32 inventoried bridges · 1 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Butte County tracks close to typical: 1 of its 32 inventoried bridges (3.1%) are rated poor, against a national rate of about 7%.
- 1 of the 32 bridges in Butte County, Idaho, are rated in poor condition (3.1%) in the 2025 National Bridge Inventory, as of .
- 9 bridges (28.1%) are rated good and 22 (68.8%) fair.
- The median Butte County bridge was built in 1978.
- The busiest poor-rated bridge is Adams Boulevard over Adams Drainage (built 1993), carrying about 491 vehicles a day.
Good 28.1% · Fair 68.8% · Poor 3.1% of 32 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 |
|---|---|---|---|
| Adams Boulevard over Adams Drainage | 1993 | 491 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 20 over Inl Central Connector | 1993 | 4,400 | Fair |
| US 20 over Big Lost River | 1977 | 2,700 | Good |
| US 93 over Arco Canal | 1962 | 2,600 | Good |
| US 93 over Spring Creek | 1962 | 2,600 | Good |
| US 93 over Big Lost River | 1962 | 2,600 | Fair |
| US 93 over Big Lost River | 1958 | 2,300 | Fair |
| Stc 6749;2500N over Big Lost River | 1926 | 500 | Fair |
| Adams Boulevard over Adams Drainage | 1993 | 491 | Poor |
| Stc 6749; 3300W over Big Lost River | 1926 | 290 | Fair |
| 2700 N over E.branch Big Lost River | 1987 | 280 | 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.