US Bridges

LA0589 over Alligator Bayou

PoorPosted for load

West Carroll Parish, Louisiana · .6 MI East of LA 17 · Structure no. 056208621400641

Built
1957
68 years old
Condition
Poor
inspected January 2023
Type
Slab
Concrete
Length
57 ft
3 main spans
Daily traffic
233
2021 count
Owner
State
State Highway Agency

About this bridge

LA0589 over Alligator Bayou is a concrete slab carrying LA0589 over Alligator Bayou in West Carroll Parish, Louisiana. It was built in 1957, so it is 68 years old, older than the Louisiana average of 43 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for load restriction.

It carries about 233 vehicles a day, roughly 15% of them trucks, projected to reach 256 by 2041. The structure is 57 ft (17.4 m) long and 27 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesLA0589
CrossesAlligator Bayou
Location.6 MI East of LA 17
RouteState Highway 589
Coordinates32.79187, -91.4032
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating16.4 US tons
Inventory rating12.9 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans3
Design loadH 15
Structure length57 ft (17.4 m)
Longest span19 ft (5.8 m)
Deck width27 ft (8.3 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic233 (2021)
Projected traffic256 by 2041
Trucks15%
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$312,000
NavigationNo navigation control on waterway

Frequently asked questions

When was LA0589 over Alligator Bayou built?

It was built in 1957, making it 68 years old in 2025.

What condition is LA0589 over Alligator Bayou in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in January 2023.

How much traffic does LA0589 over Alligator Bayou carry?

About 233 vehicles per day (2021 count), of which roughly 15% are trucks.

How long is LA0589 over Alligator Bayou?

The structure is 57 ft (17.4 m) long with a longest span of 19 ft (5.8 m) and a deck 27 ft wide.

Who owns LA0589 over Alligator Bayou?

It is owned by the State Highway Agency.