Bridge conditions in Lake County, Montana
116 inventoried bridges · 13 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Of the 116 Lake County bridges in the federal inventory, 13 carry a poor rating. That 11.2% share is roughly 2x the national average.
- 13 of the 116 bridges in Lake County, Montana, are rated in poor condition (11.2%) in the 2025 National Bridge Inventory, as of .
- 70 bridges (60.3%) are rated good and 33 (28.4%) fair.
- The median Lake County bridge was built in 2006.
- The busiest poor-rated bridge is Irr - US 93 over Nine Pipe Reservoir (built 1933), carrying about 8,158 vehicles a day.
Good 60.3% · Fair 28.4% · Poor 11.2% of 116 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 |
|---|---|---|---|
| Irr - US 93 over Nine Pipe Reservoir | 1933 | 8,158 | Poor |
| S Main Ave over Mission Creek 052 | 1929 | 2,233 | Poor |
| S 83 Fh 15 over Lost Creek | 1953 | 1,246 | Poor |
| Glover Rd over Pablo 3A Canal 037 | 1985 | 471 | Poor |
| Light Rd over Pablo 31A Canal 036 | 2009 | 292 | Poor |
| Rocky Butte Rd over Crow Creek 070 | 1986 | 128 | Poor |
| Red Barn Rd over Little Bitterroot Rv 064 | 1960 | 100 | Poor |
| Seifert Rd over Pablo A Canal 083 | 1960 | 100 | Poor |
| Schaefer Rd over Pablo Feeder Canal 086 | 1985 | 100 | Poor |
| Jocko Canyon Rd over Jocko River 011 | 1975 | 100 | Poor |
| Eagle Pass Trail over Pablo Feeder Canal 104 | 1977 | 100 | Poor |
| Allison Rd over Pablo Feeder Canal 046 | 1960 | 100 | Poor |
| Irr Bia Rte 1012 over Dry Creek Canal | 1975 | 50 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Irr - US 93 over Pablo Feeder Canal | 2006 | 15,997 | Good |
| US 93 over Wildlife Crossing | 2007 | 10,897 | Good |
| US 93 over Wildlife Crossing | 2007 | 10,897 | Good |
| US 93 over Agricultural Crossing | 2007 | 10,897 | Good |
| Irr - US 93 over Jocko River | 2005 | 8,775 | Good |
| US 93 over Spring Creek | 2006 | 8,775 | Good |
| US 93 over Wildlife Underpass | 2006 | 8,775 | Good |
| US 93 over Wildlife Underpass | 2006 | 8,775 | Good |
| US 93 over Jocko River Side Channel | 2006 | 8,775 | Fair |
| US 93 over Wildlife Upass-drainage | 2006 | 8,775 | 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.