US Bridges

LA0478 over Bayou Grande

Good

Natchitoches Parish, Louisiana · 1.91 Miles East of LA 120 · Structure no. 083500000080625

Built
2013
12 years old
Condition
Good
inspected March 2024
Type
Slab
Concrete
Length
60 ft
3 main spans
Daily traffic
172
2021 count
Owner
State
State Highway Agency

About this bridge

LA0478 over Bayou Grande is a concrete slab carrying LA0478 over Bayou Grande in Natchitoches Parish, Louisiana. It was built in 2013, so it is 12 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 172 vehicles a day, roughly 14% of them trucks, projected to reach 189 by 2041. The structure is 60 ft (18.3 m) long and 33 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

Location

Open in Google Maps
CarriesLA0478
CrossesBayou Grande
Location1.91 Miles East of LA 120
RouteState Highway 478
CountyNatchitoches Parish
StateLouisiana
Coordinates31.63977, -93.09614
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.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating54.7 US tons
Inventory rating42.1 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length60 ft (18.3 m)
Longest span20 ft (6.1 m)
Deck width33 ft (10 m)
Roadway width30 ft (9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic172 (2021)
Projected traffic189 by 2041
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was LA0478 over Bayou Grande built?

It was built in 2013, making it 12 years old in 2025.

What condition is LA0478 over Bayou Grande 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 March 2024.

How much traffic does LA0478 over Bayou Grande carry?

About 172 vehicles per day (2021 count), of which roughly 14% are trucks.

How long is LA0478 over Bayou Grande?

The structure is 60 ft (18.3 m) long with a longest span of 20 ft (6.1 m) and a deck 33 ft wide.

Who owns LA0478 over Bayou Grande?

It is owned by the State Highway Agency.