LA0427 over Bayou Manchac
Ascension Parish, Louisiana · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- LA0427 over Bayou Manchac in Ascension Parish, Louisiana, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- It was built in 1972, making it 53 years old at the 2025 inventory.
- It carries about 11,384 vehicles a day (traffic count year 2021).
- Its listed owner is the state highway agency.
- 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 → (30.33546, -91.0121)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 6 | Satisfactory condition |
| Superstructure | 6 | Satisfactory condition |
| Substructure | 4 | Poor condition |
Bridge details
| Structure | Concrete slab |
| Length | about 113 ft |
| Location | 2.1 Mi W of La 42 |
| NBI structure number | 611708172300001 |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Louisiana department of transportation.
All bridges nearby: Ascension Parish, LA bridge conditions · Louisiana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.