US Bridges

LA0494 over Bayou Poisson

Fair

Natchitoches Parish, Louisiana · 3.04 Mi. N of Int LA119 · Structure no. 083508350603041

Built
1950
75 years old
Condition
Fair
inspected April 2024
Type
Slab
Concrete
Length
100 ft
5 main spans
Daily traffic
18,361
2021 count
Owner
State
State Highway Agency

About this bridge

LA0494 over Bayou Poisson is a concrete slab carrying LA0494 over Bayou Poisson in Natchitoches Parish, Louisiana. It was built in 1950, so it is 75 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 6 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 18,361 vehicles a day, roughly 14% of them trucks, projected to reach 20,197 by 2041. The structure is 100 ft (30.5 m) long and 29 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesLA0494
CrossesBayou Poisson
Location3.04 Mi. N of Int LA119
RouteState Highway 494
CountyNatchitoches Parish
StateLouisiana
Coordinates31.71204, -93.0176
Functional classRural Major Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Last inspectionApril 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating36 US tons
Inventory rating21.1 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans5
Design loadH 15
Structure length100 ft (30.5 m)
Longest span20 ft (6.1 m)
Deck width29 ft (8.9 m)
Roadway width24 ft (7.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic18,361 (2021)
Projected traffic20,197 by 2041
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 LA0494 over Bayou Poisson built?

It was built in 1950, making it 75 years old in 2025.

What condition is LA0494 over Bayou Poisson 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 April 2024.

How much traffic does LA0494 over Bayou Poisson carry?

About 18,361 vehicles per day (2021 count), of which roughly 14% are trucks.

How long is LA0494 over Bayou Poisson?

The structure is 100 ft (30.5 m) long with a longest span of 20 ft (6.1 m) and a deck 29 ft wide.

Who owns LA0494 over Bayou Poisson?

It is owned by the State Highway Agency.