Bridge conditions in Ada County, Idaho
302 inventoried bridges · 3 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
The federal inventory lists 302 bridges in Ada County: 134 rated good, 165 fair, and 3 poor.
- 3 of the 302 bridges in Ada County, Idaho, are rated in poor condition (1.0%) in the 2025 National Bridge Inventory, as of .
- 134 bridges (44.4%) are rated good and 165 (54.6%) fair.
- The median Ada County bridge was built in 1991.
- The busiest poor-rated bridge is Sma 7643;HEALY Rd over New York Canal (built 1964), carrying about 7,000 vehicles a day.
Good 44.4% · Fair 54.6% · Poor 1.0% of 302 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 |
|---|---|---|---|
| Sma 7643;HEALY Rd over New York Canal | 1964 | 7,000 | Poor |
| Sma 7643;ECKERT Rd over Ridenbaugh Canal | 1954 | 6,700 | Poor |
| Sma 7643;ECKERT Rd over Boise River(barber Br) | 1954 | 6,700 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I 84 Ebl & Wbl over Ridenbaugh Canal | 1966 | 144,500 | Fair |
| I 84 over Ten Mile Creek | 1965 | 131,000 | Fair |
| I 184B Ebl & Wbl over S7403;UPRR;FRANKLIN Ic | 2001 | 76,500 | Good |
| I 184B Ebl & Wbl over S7073;CANAL;COLE Rd | 2001 | 76,500 | Fair |
| I 184 Ebl over I 84 Wbl | 2001 | 68,500 | Good |
| SH 55;EAGLE Road over I 84 Eb-wb;eagle Rd Ic | 1990 | 58,000 | Fair |
| I 184;W Fairview over Settlers Canal | 1967 | 56,500 | Fair |
| I 84 over SH 21;GOWEN Rd Ic | 2015 | 52,000 | Good |
| SH 69 over Ten Mile Creek | 1963 | 49,500 | Fair |
| I 84 Ebl over New York Canal | 1968 | 45,750 | Good |
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.