US Bridges

LA0057 over Dulac Bayou

Fair

Terrebonne Parish, Louisiana · 8 MI North of LA 56 · Structure no. 025502460117211

Built
1971
54 years old
Condition
Fair
inspected March 2024
Type
Movable - Swing
Steel
Length
462 ft
1 main span
Daily traffic
952
2021 count
Owner
State
State Highway Agency

About this bridge

LA0057 over Dulac Bayou is a steel movable - swing carrying LA0057 over Dulac Bayou in Terrebonne Parish, Louisiana. It was built in 1971, so it is 54 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 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 952 vehicles a day, roughly 5% of them trucks, projected to reach 1,047 by 2041. The structure is 462 ft (140.8 m) long and 32 ft wide. If it were closed, the detour would be 14.3 mi (23 km).

Location

Open in Google Maps
CarriesLA0057
CrossesDulac Bayou
Location8 MI North of LA 56
RouteState Highway 57
CountyTerrebonne Parish
StateLouisiana
Coordinates29.37416, -90.71175
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating31.4 US tons
Inventory rating23.9 US tons

Structure

Structure typeMovable - Swing
MaterialSteel
DeckOpen grating
Main spans1 (+16 approach)
Design loadHS 20
Structure length462 ft (140.8 m)
Longest span135 ft (41.1 m)
Deck width32 ft (9.9 m)
Roadway width25 ft (7.5 m)
Vertical clearance over deck19 ft (5.7 m)

Traffic and service

Average daily traffic952 (2021)
Projected traffic1,047 by 2041
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.3 mi (23 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—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was LA0057 over Dulac Bayou built?

It was built in 1971, making it 54 years old in 2025.

What condition is LA0057 over Dulac Bayou 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 March 2024.

How much traffic does LA0057 over Dulac Bayou carry?

About 952 vehicles per day (2021 count), of which roughly 5% are trucks.

How long is LA0057 over Dulac Bayou?

The structure is 462 ft (140.8 m) long with a longest span of 135 ft (41.1 m) and a deck 32 ft wide.

Who owns LA0057 over Dulac Bayou?

It is owned by the State Highway Agency.