Bridge conditions in Missoula County, Montana
206 inventoried bridges · 15 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Missoula County tracks close to typical: 15 of its 206 inventoried bridges (7.3%) are rated poor, against a national rate of about 7%.
- 15 of the 206 bridges in Missoula County, Montana, are rated in poor condition (7.3%) in the 2025 National Bridge Inventory, as of .
- 66 bridges (32.0%) are rated good and 125 (60.7%) fair.
- The median Missoula County bridge was built in 1971.
- The busiest poor-rated bridge is I 90 over Int Reserve Street (built 1966), carrying about 13,664 vehicles a day.
Good 32.0% · Fair 60.7% · Poor 7.3% of 206 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 90 over Int Reserve Street | 1966 | 13,664 | Poor |
| I 90 over Clark Fork River | 1964 | 9,168 | Poor |
| Lolo St over Rattlesnake Creek 009 | 1966 | 2,363 | Poor |
| Mullan Rd over Irrigation Canal | 1970 | 1,635 | Poor |
| S 474 over RR | 1959 | 1,397 | Poor |
| US 12 Fh 11 over Lolo Creek | 1957 | 799 | Poor |
| Hwy 10 W over Ninemile Creek 035 | 1924 | 141 | Poor |
| Hwy 10 W over Ninemile Slide 026 | 1947 | 141 | Poor |
| Turah Rd over Clark Fork 103 | 1962 | 100 | Poor |
| Placid Lake Rd over Owl Creek 077 | 1970 | 100 | Poor |
| Sunset Hill Rd over Blackfoot River 088 | 1907 | 100 | Poor |
| Boy Scout Rd over Clearwater River 082 | 1938 | 100 | Poor |
| Gilbert CR. Rd over Rock Creek | 1982 | 50 | Poor |
| Wahlquist Br Road over Rock Creek | 1961 | 50 | Poor |
| Finley CR Rd over Placid CR | 1959 | 50 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| N Reserve St over Clark Fork R Flood Plain | 1977 | 35,914 | Fair |
| N Reserve St over Clark Fork River | 1975 | 35,914 | Fair |
| Reserve St over W Broadway St-rr | 1998 | 29,572 | Fair |
| Brooks St-us 12 over Bitterroot River | 1968 | 28,185 | Fair |
| I 90 over Grant Creek | 1965 | 27,328 | Good |
| N Russel Street over Clark Fork River | 2020 | 23,274 | Good |
| S Orange St over Pedestrian-bike Path | 2002 | 22,608 | Good |
| S Orange St over Clark Fork River | 2003 | 22,608 | Fair |
| US 12-e Broadway S over Rattlesnake Creek | 1964 | 21,390 | Fair |
| US 93 over Lolo Creek | 1965 | 20,994 | Good |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of Montana: Montana 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.