S 13 over Duck Creek
McCone County, Montana · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- S 13 over Duck Creek in McCone County, Montana, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1992, making it 33 years old at the 2025 inventory.
- It carries about 792 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 34 of the 43 inventoried bridges in McCone County rated fair (79.1%); 4 (9.3%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (fair), but component ratings moved: superstructure 7 to 8.
- Its most recent inspection on record is dated January 2025, on a 24-month routine inspection cycle.
- A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (47.6176, -105.49594)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 8 | Very good condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 97 ft |
| Location | 14M NE Circle |
| NBI structure number | P00025014+09561 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | January 2025 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Montana department of transportation.
Busiest bridges in McCone County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| S 200 over Redwater River | 1933 | 1,263 | Fair |
| Irr - S 13 over Drainage | 1995 | 985 | Fair |
| Irr - S 13 over Drainage-stockpass | 1995 | 985 | Good |
| Irr - S 13 over Nickwall Creek | 1995 | 985 | Fair |
| S 200S over Buffalo Spring Creek | 1966 | 971 | Fair |
| S 13 over Horse Creek | 1988 | 910 | Fair |
All bridges nearby: McCone County, MT bridge conditions · every bridge in McCone County · Montana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.