I0310 over Mississippi River
St. Charles Parish, Louisiana · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- I0310 over Mississippi River in St. Charles Parish, Louisiana, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1983, making it 42 years old at the 2025 inventory.
- It carries about 47,396 vehicles a day (traffic count year 2021).
- Its listed owner is the state highway agency.
- It is one of 32 of the 82 inventoried bridges in St. Charles Parish rated fair (39.0%); 1 (1.2%) 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 February 2023, on a 24-month routine inspection cycle.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- 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 → (29.9446, -90.37292)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 5 | 5 | Fair condition |
Bridge details
| Structure | Continuous steel cable-stayed girder |
| Length | about 2,745 ft |
| Location | 4.4 Mi S of US 61 |
| NBI structure number | 024504503700001 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | February 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 7: scour countermeasures installed |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Louisiana department of transportation.
Busiest bridges in St. Charles Parish
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I0310 over Swamp | 1992 | 56,783 | Good |
| US0090 over Drain Ditch | 1999 | 49,920 | Good |
| US0090 over US 90 Turnarounds | 2013 | 49,920 | Good |
| US0090 over Davis Pond Diversion | 2002 | 49,920 | Good |
| US0090 over Drain Canal | 1953 | 49,920 | Fair |
| US0090 over Sellers Canal | 1953 | 49,920 | Fair |
All bridges nearby: St. Charles Parish, LA bridge conditions · every bridge in St. Charles Parish · Louisiana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.