Bridge conditions in Carlton County, Minnesota
148 inventoried bridges · 13 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
The federal inventory lists 148 bridges in Carlton County: 72 rated good, 63 fair, and 13 poor.
- 13 of the 148 bridges in Carlton County, Minnesota, are rated in poor condition (8.8%) in the 2025 National Bridge Inventory, as of .
- 72 bridges (48.6%) are rated good and 63 (42.6%) fair.
- The median Carlton County bridge was built in 1984.
- The busiest poor-rated bridge is I 35 over Moose Horn River (built 1968), carrying about 8,200 vehicles a day.
Good 48.6% · Fair 42.6% · Poor 8.8% of 148 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 35 over Moose Horn River | 1968 | 8,200 | Poor |
| I 35 over Moose Horn River | 1968 | 8,200 | Poor |
| Csah 61 over BNSF RR | 1979 | 2,884 | Poor |
| Csah 26 over I 35 | 1965 | 1,343 | Poor |
| Csah 1 over Mp; L Canal | 1976 | 1,006 | Poor |
| Csah 6 over Blackhoof Creek | 1918 | 420 | Poor |
| Csah 12 over Kettle River | 1964 | 300 | Poor |
| Csah 4 over Kettle River | 1935 | 278 | Poor |
| M 1 over Tamarack River | 1940 | 180 | Poor |
| CR 138 over Moose Horn River | 1978 | 164 | Poor |
| Ut 264 over Ditch | 1983 | 56 | Poor |
| Ut 1103 over Ditch | 1983 | 3 | Poor |
| Ut 388 over Hasty Brook | 1935 | 1 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I 35 over Portage River | 1968 | 16,400 | Fair |
| Mn 33 over I 35 | 1965 | 16,100 | Fair |
| I 35 over St Louis River | 1971 | 14,250 | Fair |
| I 35 over St Louis River | 1971 | 14,250 | Fair |
| I 35 over Korby Road | 1973 | 14,250 | Good |
| I 35 over Korby Road | 1973 | 14,250 | Good |
| I 35 over Midway River | 1971 | 14,250 | Good |
| I 35 over Midway River | 1971 | 14,250 | Good |
| Mn 33 over St Louis River | 1995 | 13,800 | Fair |
| Mn 33 over St Louis R BNSF RR; St | 1997 | 13,800 | Fair |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of Minnesota: Minnesota 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.