US Bridges

LA0507 over Blacklake Bayou Relief

Fair

Bienville Parish, Louisiana · 4.31 MI West of LA 153 · Structure no. 040701000300251

Built
2000
25 years old
Condition
Fair
inspected April 2024
Type
Slab
Concrete
Length
437 ft
23 main spans
Daily traffic
582
2021 count
Owner
State
State Highway Agency

About this bridge

LA0507 over Blacklake Bayou Relief is a concrete slab carrying LA0507 over Blacklake Bayou Relief in Bienville Parish, Louisiana. It was built in 2000, so it is 25 years old, younger 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 582 vehicles a day, roughly 19% of them trucks, projected to reach 640 by 2041. The structure is 437 ft (133.2 m) long and 35 ft wide. If it were closed, the detour would be 11.8 mi (19 km).

Location

Open in Google Maps
CarriesLA0507
CrossesBlacklake Bayou Relief
Location4.31 MI West of LA 153
RouteState Highway 507
CountyBienville Parish
StateLouisiana
Coordinates32.20575, -93.2102
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionApril 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
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 rating99 US tons
Inventory rating64 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans23
Design loadHS 20
Structure length437 ft (133.2 m)
Longest span19 ft (5.8 m)
Deck width35 ft (10.6 m)
Roadway width31 ft (9.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic582 (2021)
Projected traffic640 by 2041
Trucks19%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesRelief for waterway
Detour if closed11.8 mi (19 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 LA0507 over Blacklake Bayou Relief built?

It was built in 2000, making it 25 years old in 2025.

What condition is LA0507 over Blacklake Bayou Relief 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 LA0507 over Blacklake Bayou Relief carry?

About 582 vehicles per day (2021 count), of which roughly 19% are trucks.

How long is LA0507 over Blacklake Bayou Relief?

The structure is 437 ft (133.2 m) long with a longest span of 19 ft (5.8 m) and a deck 35 ft wide.

Who owns LA0507 over Blacklake Bayou Relief?

It is owned by the State Highway Agency.