Bridge conditions in Gem County, Idaho
57 inventoried bridges · 3 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
3 of the 57 bridges the federal inventory lists in Gem County are rated poor; the rest split 14 good and 40 fair.
- 3 of the 57 bridges in Gem County, Idaho, are rated in poor condition (5.3%) in the 2025 National Bridge Inventory, as of .
- 14 bridges (24.6%) are rated good and 40 (70.2%) fair.
- The median Gem County bridge was built in 1973.
- The busiest poor-rated bridge is Cascade Road over Enterprise Canal (built 1950), carrying about 950 vehicles a day.
Good 24.6% · Fair 70.2% · Poor 5.3% of 57 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 |
|---|---|---|---|
| Cascade Road over Enterprise Canal | 1950 | 950 | Poor |
| Little Rock Road over Noble Drain | 1955 | 50 | Poor |
| Rammage Meadows Rd over Third Fk.chief Eagle Eye | 1963 | 20 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| SH 16 over Black Canyon Canal | 1966 | 12,000 | Fair |
| SH 52 over Farmers Coop Canal | 1992 | 11,500 | Good |
| SH 52 over Payette River;emmett Br. | 1971 | 10,500 | Fair |
| SH 52 over Farmers Coop Canal | 2001 | 7,000 | Good |
| SMA7190;SUBSTATION over Last Chance Canal | 2016 | 6,800 | Good |
| SH 52 over Drain Ditch | 1988 | 3,500 | Fair |
| SH 52 over Noble Canal | 1990 | 3,000 | Fair |
| STC3831;LTL Frzout over Black Canyon Canal | 1973 | 2,500 | Fair |
| SH 52 over Squaw Creek | 1956 | 2,100 | Fair |
| STC7409;W 4TH St over Farmers Coop Canal | 1960 | 1,800 | 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.