Bridge conditions in Fergus County, Montana
158 inventoried bridges · 9 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Fergus County tracks close to typical: 9 of its 158 inventoried bridges (5.7%) are rated poor, against a national rate of about 7%.
- 9 of the 158 bridges in Fergus County, Montana, are rated in poor condition (5.7%) in the 2025 National Bridge Inventory, as of .
- 52 bridges (32.9%) are rated good and 97 (61.4%) fair.
- The median Fergus County bridge was built in 1979.
- The busiest poor-rated bridge is US 87 over Drainage (built 1939), carrying about 1,067 vehicles a day.
Good 32.9% · Fair 61.4% · Poor 5.7% of 158 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 |
|---|---|---|---|
| US 87 over Drainage | 1939 | 1,067 | Poor |
| US 191 over Missouri River | 1959 | 655 | Poor |
| 6TH Ave S over Big Spring Creek 133 | 1962 | 437 | Poor |
| US 191 over Box Elder Creek | 1942 | 382 | Poor |
| Fairview Rd over S Fork Mcdonald CR 123 | 1962 | 100 | Poor |
| N Dawes Street over Big Spring Creek 061 | 1940 | 100 | Poor |
| W Broadway Street over Big Spring Creek 062 | 1940 | 100 | Poor |
| Third Avenue S over Little Casino Creek 138 | 2006 | 100 | Poor |
| Road 220 over Carroll Coulee | 1963 | 1 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 87-e Main St over Mill Ditch | 1922 | 8,747 | Fair |
| US 87-w Main St over Big Spring Creek | 1962 | 5,357 | Fair |
| US 191-1st Ave N over Big Spring Creek | 1960 | 5,189 | Fair |
| US 87 over Boyd Creek | 1942 | 2,831 | Fair |
| US 191-kendall Rd over Big Spring Creek | 1976 | 2,663 | Fair |
| US 87 over Beaver Creek | 2009 | 2,589 | Good |
| US 87 over Cottonwood Creek | 2009 | 2,589 | Fair |
| W Brassey St over Big Spring Creek | 1920 | 2,412 | Fair |
| US 191 over Dawkins Branch | 2021 | 2,328 | Good |
| US 87 over Rock Creek | 2021 | 2,319 | 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.