Bridge conditions in Siskiyou County, California
425 inventoried bridges · 25 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
The federal inventory lists 425 bridges in Siskiyou County: 170 rated good, 230 fair, and 25 poor.
- 25 of the 425 bridges in Siskiyou County, California, are rated in poor condition (5.9%) in the 2025 National Bridge Inventory, as of .
- 170 bridges (40.0%) are rated good and 230 (54.1%) fair.
- The median Siskiyou County bridge was built in 1969.
- The busiest poor-rated bridge is Interstate 5 over Panorama Road (built 1960), carrying about 18,000 vehicles a day.
Good 40.0% · Fair 54.1% · Poor 5.9% of 425 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 |
|---|---|---|---|
| Interstate 5 over Panorama Road | 1960 | 18,000 | Poor |
| State Route 96 over Thompson Creek | 1952 | 615 | Poor |
| State Route 96 over Scott River | 1957 | 600 | Poor |
| N Old Stage Rd over Shasta River | 1968 | 379 | Poor |
| Lake View Road over Klamath River | 1960 | 226 | Poor |
| Salmon River Road over Salmon River | 1966 | 210 | Poor |
| Hospital Road over Yreka Creek | 1987 | 200 | Poor |
| Eller Lane over Scott River | 1910 | 172 | Poor |
| West Beaver Road over West Fork Beaver Creek | 1983 | 50 | Poor |
| Trapper Road over Trapper Creek | 1978 | 50 | Poor |
| South Russian Road over Russian Creek | 1966 | 50 | Poor |
| China Mt. Road over Houston Creek | 1974 | 50 | Poor |
| Boulder Road over East Boulder Creek | 1966 | 50 | Poor |
| Camp Eden Road over Duck Lake Creek | 1949 | 50 | Poor |
| Tom Walker Road over Tompkins Creek | 1988 | 50 | Poor |
| No Data Entered over West Boulder Creek | 2004 | 50 | Poor |
| No Data Entered over Elk Creek | 1971 | 30 | Poor |
| Horse Creek Rd over Klamath River | 1930 | 21 | Poor |
| Wildcat Creek Road over Scott River | 1909 | 20 | Poor |
| Independence Road over Independence Creek | 1970 | 20 | Poor |
| Methodist Ck Road over S. Fk. Salmon River | 1963 | 20 | Poor |
| Old Cottonwood CR over Cottonwood Creek | 1957 | 10 | Poor |
| Road over Mid Fk Applegate | 1963 | 10 | Poor |
| Road over Butte Fork Creek | 1951 | 10 | Poor |
| No Data Entered over Boulder Creek | 1967 | 2 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Interstate 5 SB over UP RR & Amtrak | 1964 | 20,000 | Fair |
| Interstate 5 NB over UP RR & Amtrak | 1964 | 20,000 | Fair |
| Interstate 5 over Mott Road | 1976 | 20,000 | Good |
| Interstate 5 over Mott Road | 1976 | 20,000 | Fair |
| Interstate 5 over Dunsmuir Ave | 1976 | 19,200 | Good |
| Interstate 5 over Sacramento UP RR Amtrak | 1955 | 18,000 | Good |
| Interstate 5 over Little Castle Creek | 1960 | 18,000 | Fair |
| Interstate 5 over Dunsmuir Ave | 1960 | 18,000 | Good |
| Interstate 5 over Panorama Road | 1960 | 18,000 | Poor |
| Interstate 5 over Oak Street | 1960 | 18,000 | Good |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of California: California 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.