US Bridges

LA0504 over Sibley Lake

Good

Natchitoches Parish, Louisiana · 1.7 Mi. N of Int LA6 · Structure no. 083508350501701

Built
2005
20 years old
Condition
Good
inspected February 2024
Type
Slab
Concrete
Length
180 ft
9 main spans
Daily traffic
1,737
2021 count
Owner
State
State Highway Agency

About this bridge

LA0504 over Sibley Lake is a concrete slab carrying LA0504 over Sibley Lake in Natchitoches Parish, Louisiana. It was built in 2005, so it is 20 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 1,737 vehicles a day, roughly 8% of them trucks, projected to reach 1,910 by 2041. The structure is 180 ft (54.9 m) long and 32 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesLA0504
CrossesSibley Lake
Location1.7 Mi. N of Int LA6
RouteState Highway 504
Coordinates31.75081, -93.1555
Functional classUrban 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 protection7 GoodSome minor problems.
Last inspectionFebruary 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 adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating56.1 US tons
Inventory rating43.2 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans9
Design loadHS 20
Structure length180 ft (54.9 m)
Longest span20 ft (6.1 m)
Deck width32 ft (9.8 m)
Roadway width29 ft (8.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,737 (2021)
Projected traffic1,910 by 2041
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 LA0504 over Sibley Lake built?

It was built in 2005, making it 20 years old in 2025.

What condition is LA0504 over Sibley Lake 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 February 2024.

How much traffic does LA0504 over Sibley Lake carry?

About 1,737 vehicles per day (2021 count), of which roughly 8% are trucks.

How long is LA0504 over Sibley Lake?

The structure is 180 ft (54.9 m) long with a longest span of 20 ft (6.1 m) and a deck 32 ft wide.

Who owns LA0504 over Sibley Lake?

It is owned by the State Highway Agency.