US Bridges

LA0315 over Bayou Dularge

Fair

Terrebonne Parish, Louisiana · .01 MI North of LA 661 · Structure no. 025502459009801

Built
1977
48 years old
Condition
Fair
inspected October 2023
Type
Movable - Bascule
Steel
Length
2,311 ft
1 main span
Daily traffic
12,596
2021 count
Owner
State
State Highway Agency

About this bridge

LA0315 over Bayou Dularge is a steel movable - bascule carrying LA0315 over Bayou Dularge in Terrebonne Parish, Louisiana. It was built in 1977, so it is 48 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 12,596 vehicles a day, roughly 11% of them trucks, projected to reach 13,855 by 2041. The structure is 2,311 ft (704.4 m) long and 39 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesLA0315
CrossesBayou Dularge
Location.01 MI North of LA 661
RouteState Highway 315
CountyTerrebonne Parish
StateLouisiana
Coordinates29.56727, -90.7177
Functional classUrban Minor Arterial

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.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating47 US tons
Inventory rating32 US tons

Structure

Structure typeMovable - Bascule
MaterialSteel
DeckOpen grating
Main spans1 (+34 approach)
Design loadHS 20
Structure length2,311 ft (704.4 m)
Longest span150 ft (45.7 m)
Deck width39 ft (12 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,596 (2021)
Projected traffic13,855 by 2041
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway and waterway
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 proposedNone recorded
Estimated improvement cost—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was LA0315 over Bayou Dularge built?

It was built in 1977, making it 48 years old in 2025.

What condition is LA0315 over Bayou Dularge 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 October 2023.

How much traffic does LA0315 over Bayou Dularge carry?

About 12,596 vehicles per day (2021 count), of which roughly 11% are trucks.

How long is LA0315 over Bayou Dularge?

The structure is 2,311 ft (704.4 m) long with a longest span of 150 ft (45.7 m) and a deck 39 ft wide.

Who owns LA0315 over Bayou Dularge?

It is owned by the State Highway Agency.