6TH Ave S over Big Spring Creek 133
Fergus County, Montana · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 6TH Ave S over Big Spring Creek 133 in Fergus County, Montana, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1962 and reconstructed in 1975, making it 63 years old at the 2025 inventory.
- It carries about 437 vehicles a day (traffic count year 2023).
- Its listed owner is a city or municipal highway agency.
- It is one of 9 of the 158 inventoried bridges in Fergus County rated poor (5.7%); 9 (5.7%) are rated poor.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (47.05426, -109.41818)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 6 | Satisfactory condition |
| Superstructure | 6 | Satisfactory condition |
| Substructure | 4 | Poor condition |
Bridge details
| Structure | Prestressed concrete slab |
| Length | about 50 ft |
| Location | Lewistown-6th Ave S |
| NBI structure number | M14071000+00201 |
| Condition class | Poor |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Montana department of transportation.
Busiest bridges in Fergus 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 |
All bridges nearby: Fergus County, MT bridge conditions · every bridge in Fergus County · Montana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.