US Bridges

Theriot Voisin Br over Du Large Bayou

FairPosted for load

Terrebonne Parish, Louisiana · 0001 Log MI from in · Structure no. 025529248904681

Built
2011
14 years old
Condition
Fair
inspected May 2023
Type
Movable - Bascule
Steel
Length
89 ft
4 main spans
Daily traffic
1,156
2023 count
Owner
County
County Highway Agency

About this bridge

Theriot Voisin Br over Du Large Bayou is a steel movable - bascule carrying Theriot Voisin Br over Du Large Bayou in Terrebonne Parish, Louisiana. It was built in 2011, so it is 14 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 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 1,156 vehicles a day, projected to reach 1,271 by 2043. The structure is 89 ft (27.1 m) long and 22 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesTheriot Voisin Br
CrossesDu Large Bayou
Location0001 Log MI from in
RouteCounty Highway 0
CountyTerrebonne Parish
StateLouisiana
Coordinates29.41309, -90.7819
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating40.3 US tons
Inventory rating31.1 US tons

Structure

Structure typeMovable - Bascule
MaterialSteel
DeckWood or timber
Main spans4
Design loadH 10
Structure length89 ft (27.1 m)
Longest span28 ft (8.5 m)
Deck width22 ft (6.8 m)
Roadway width21 ft (6.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,156 (2023)
Projected traffic1,271 by 2043
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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$313,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Theriot Voisin Br over Du Large Bayou built?

It was built in 2011, making it 14 years old in 2025.

What condition is Theriot Voisin Br over Du Large 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 May 2023.

How much traffic does Theriot Voisin Br over Du Large Bayou carry?

About 1,156 vehicles per day (2023 count).

How long is Theriot Voisin Br over Du Large Bayou?

The structure is 89 ft (27.1 m) long with a longest span of 28 ft (8.5 m) and a deck 22 ft wide.

Who owns Theriot Voisin Br over Du Large Bayou?

It is owned by the County Highway Agency.