Bridge conditions in Shoshone County, Idaho
261 inventoried bridges · 26 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
About one in 10 bridges in Shoshone County is rated in poor condition: 26 of 261 on the federal inventory, one of the higher shares in Idaho.
- 26 of the 261 bridges in Shoshone County, Idaho, are rated in poor condition (10.0%) in the 2025 National Bridge Inventory, as of .
- 61 bridges (23.4%) are rated good and 174 (66.7%) fair.
- The median Shoshone County bridge was built in 1973.
- The busiest poor-rated bridge is I 90B over S.fk.cda R;i-90b Arch (built 1940), carrying about 2,300 vehicles a day.
Good 23.4% · Fair 66.7% · Poor 10.0% of 261 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 |
|---|---|---|---|
| I 90B over S.fk.cda R;i-90b Arch | 1940 | 2,300 | Poor |
| Bunker Ave over S.fk.coeur Dalene River | 1971 | 1,900 | Poor |
| Old River Road over Stc 5752;N.FK.CDA River | 1930 | 1,200 | Poor |
| STC5752;CDA Rvr Rd over Coeur Dalene River | 1951 | 960 | Poor |
| SH 3 over St Maries River | 1955 | 460 | Poor |
| Stc 5711;MOON Pass over Big Dick Creek | 1909 | 370 | Poor |
| Third Street over S.fk.coeur Dalene River | 1978 | 360 | Poor |
| Cooper Pass Road over Canyon Creek | 2012 | 220 | Poor |
| Pine Drive; Nf 301 over W.fk.st Maries River | 1973 | 130 | Poor |
| Mill Road over I 90;MILL Road Ic | 1963 | 110 | Poor |
| Potlatch Road over Elk Creek Trestle | 1912 | 100 | Poor |
| Potlatch Road over Big Creek Trestle | 1912 | 100 | Poor |
| Potlatch Road over Agatha Creek Trestle | 1912 | 100 | Poor |
| Potlatch Road over Black Prince Trestle | 1912 | 100 | Poor |
| Fifth Street over S.fk.coeur Dalene River | 1972 | 50 | Poor |
| Fs Route No. 2361 over Beaver Creek | 1983 | 50 | Poor |
| Fs Route No. 409 over W.f. Steamboat Creek | 1956 | 50 | Poor |
| Fs Route No. 257 over Steamboat Creek | 1956 | 50 | Poor |
| Fs Route No. 1221 over Gold Creek | 1963 | 50 | Poor |
| Fs Route 225 over St Joe River | 1934 | 50 | Poor |
| Fs Route No. 456A over N.f. St Joe River | 1935 | 50 | Poor |
| Fs Route No. 537 over Big Creek | 1939 | 50 | Poor |
| Northside Rd over Black Prince Creek | 1965 | 40 | Poor |
| I 90RAMP EB Off over S.fk.cda R.;eb Off Ramp | 1964 | 20 | Poor |
| Old Mil. RR Grade over Slough Bridge | 1912 | 15 | Poor |
| Old Mil. RR Grade over Trout Creek | 1912 | 15 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I 90 over Stc 5766;SILVERTON Ic | 1978 | 11,000 | Fair |
| I 90 EB & WB over S.fk.cda R;fr.rd. | 1978 | 11,000 | Fair |
| I 90 over S.fk.coeur Dalene River | 1987 | 11,000 | Fair |
| I 90 Ebl & Wbl over Crossroad Bd;w.wallace I | 1987 | 11,000 | Fair |
| I 90 over I 90B;CANYON CR | 1991 | 11,000 | Fair |
| I 90 Spur over Canyon Creek | 1940 | 10,500 | Fair |
| I 90 Ebl & Wbl over S.fk.coeur Dalene River | 1962 | 10,500 | Fair |
| I 90 Ebl & Wbl over S.fk.coeur Dalene River | 1962 | 10,500 | Fair |
| I 90 Ebl & Wbl over S.fk.coeur Dalene River | 1962 | 10,500 | Fair |
| I 90 Ebl & Wbl over I 90 EB Off;w.mullan Ic | 1973 | 9,600 | 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.