US0171 over Diamond Gully
Calcasieu Parish, Louisiana · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US0171 over Diamond Gully in Calcasieu Parish, Louisiana, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1996, making it 29 years old at the 2025 inventory.
- It carries about 32,659 vehicles a day (traffic count year 2021).
- Its listed owner is the state highway agency.
- It is one of 339 of the 462 inventoried bridges in Calcasieu Parish rated fair (73.4%); 39 (8.4%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated May 2023, 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 → (30.35448, -93.20023)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 5 | Fair condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 5 | 5 | Fair condition |
Bridge details
| Structure | Concrete slab |
| Length | about 80 ft |
| Location | 3.6 Mi N of La 378-us171 |
| NBI structure number | 071000240204001 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | May 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Louisiana department of transportation.
Busiest bridges in Calcasieu Parish
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I0010 over Sabine Relief | 1954 | 86,969 | Poor |
| I0010 over Gum Gully | 1966 | 86,969 | Fair |
| I0010 over Vinton Canal | 1966 | 86,969 | Fair |
| I0010 over Hamptons Coulee | 1966 | 86,969 | Fair |
| I0010 over Coone Gully | 1965 | 86,969 | Fair |
| I0010 over Drain | 1966 | 86,969 | Fair |
All bridges nearby: Calcasieu Parish, LA bridge conditions · every bridge in Calcasieu Parish · Louisiana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.