US Bridges

LA0309 over Bubbling Bayou

Good

Lafourche Parish, Louisiana · 2.5 MI North of US 90 · Structure no. 022904130401571

Built
1995
30 years old
Condition
Good
inspected April 2024
Type
Slab
Concrete
Length
80 ft
4 main spans
Daily traffic
4,583
2021 count
Owner
State
State Highway Agency

About this bridge

LA0309 over Bubbling Bayou is a concrete slab carrying LA0309 over Bubbling Bayou in Lafourche Parish, Louisiana. It was built in 1995, so it is 30 years old, younger than the Louisiana average of 43 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 4,583 vehicles a day, roughly 12% of them trucks, projected to reach 5,041 by 2041. The structure is 80 ft (24.4 m) long and 43 ft wide. If it were closed, the detour would be 19.9 mi (32 km).

CarriesLA0309
CrossesBubbling Bayou
Location2.5 MI North of US 90
RouteState Highway 309
Coordinates29.73732, -90.9197
Functional classRural Minor Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating81 US tons
Inventory rating48 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length80 ft (24.4 m)
Longest span20 ft (6.1 m)
Deck width43 ft (13.1 m)
Roadway width39 ft (12 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,583 (2021)
Projected traffic5,041 by 2041
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.9 mi (32 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was LA0309 over Bubbling Bayou built?

It was built in 1995, making it 30 years old in 2025.

What condition is LA0309 over Bubbling Bayou in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in April 2024.

How much traffic does LA0309 over Bubbling Bayou carry?

About 4,583 vehicles per day (2021 count), of which roughly 12% are trucks.

How long is LA0309 over Bubbling Bayou?

The structure is 80 ft (24.4 m) long with a longest span of 20 ft (6.1 m) and a deck 43 ft wide.

Who owns LA0309 over Bubbling Bayou?

It is owned by the State Highway Agency.