Bridge conditions in Jefferson County, Idaho
125 inventoried bridges · 4 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
The federal inventory lists 125 bridges in Jefferson County: 24 rated good, 97 fair, and 4 poor.
- 4 of the 125 bridges in Jefferson County, Idaho, are rated in poor condition (3.2%) in the 2025 National Bridge Inventory, as of .
- 24 bridges (19.2%) are rated good and 97 (77.6%) fair.
- The median Jefferson County bridge was built in 1972.
- The busiest poor-rated bridge is N 4400 E (shelton) over Burgess Canal (built 1969), carrying about 510 vehicles a day.
Good 19.2% · Fair 77.6% · Poor 3.2% of 125 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 |
|---|---|---|---|
| N 4400 E (shelton) over Burgess Canal | 1969 | 510 | Poor |
| E 700 N Rd over Butte Market Lake Canal | 1962 | 61 | Poor |
| E 421 N over Lewisville Canal | 1960 | 50 | Poor |
| 2350 North over Camas Creek | 1972 | 20 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 20 over Garfield Ucon Canal | 1972 | 34,500 | Fair |
| US 20 over Burgess Canal | 1975 | 28,500 | Fair |
| US 20 Eb-wb over SH 48;RIGBY Gs | 1976 | 28,500 | Fair |
| US 20 Ebl & Wbl over Parks Lewisville Canal | 1975 | 19,500 | Fair |
| US 20 Ebl over Snake River;lorenzo Br. | 1980 | 15,250 | Fair |
| US 20 Wbl over Snake River;lorenzo Br. | 1974 | 15,250 | Fair |
| US 20 Ebl over Snake River Dry Bed Cnl | 1975 | 9,750 | Fair |
| US 20 Wbl over Snake River Dry Bed Cnl | 1975 | 9,750 | Fair |
| US 20 Ebl over Menan Canal | 1975 | 9,750 | Fair |
| US 20 Wbl over Menan Canal | 1975 | 9,750 | 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.