US Bridges

LA0403 over Bayou Lafourche

Fair

Assumption Parish, Louisiana · 0.01 MI E of LA 1 · Structure no. 610408041009651

Built
1972
53 years old
Condition
Fair
inspected July 2023
Type
Slab
Concrete
Length
171 ft
9 main spans
Daily traffic
347
2021 count
Owner
State
State Highway Agency

About this bridge

LA0403 over Bayou Lafourche is a concrete slab carrying LA0403 over Bayou Lafourche in Assumption Parish, Louisiana. It was built in 1972, so it is 53 years old, older than the Louisiana average of 43 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 347 vehicles a day, roughly 10% of them trucks, projected to reach 381 by 2041. The structure is 171 ft (52.1 m) long and 35 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesLA0403
CrossesBayou Lafourche
Location0.01 MI E of LA 1
RouteState Highway 403
CountyAssumption Parish
StateLouisiana
Coordinates29.99311, -91.05426
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating69 US tons
Inventory rating41 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans9
Design loadHS 20
Structure length171 ft (52.1 m)
Longest span19 ft (5.8 m)
Deck width35 ft (10.7 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic347 (2021)
Projected traffic381 by 2041
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 LA0403 over Bayou Lafourche built?

It was built in 1972, making it 53 years old in 2025.

What condition is LA0403 over Bayou Lafourche in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in July 2023.

How much traffic does LA0403 over Bayou Lafourche carry?

About 347 vehicles per day (2021 count), of which roughly 10% are trucks.

How long is LA0403 over Bayou Lafourche?

The structure is 171 ft (52.1 m) long with a longest span of 19 ft (5.8 m) and a deck 35 ft wide.

Who owns LA0403 over Bayou Lafourche?

It is owned by the State Highway Agency.