US Bridges

Smithridge Bridge over Petit Caillou Bayou

FairPosted for load

Terrebonne Parish, Louisiana · 0001 Log MI from in · Structure no. 025529297903441

Built
1968
57 years old
Condition
Fair
inspected June 2023
Type
Movable - Swing
Steel
Length
129 ft
1 main span
Daily traffic
438
2020 count
Owner
County
County Highway Agency

About this bridge

Smithridge Bridge over Petit Caillou Bayou is a steel movable - swing carrying Smithridge Bridge over Petit Caillou Bayou in Terrebonne Parish, Louisiana. It was built in 1968, so it is 57 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. Its operating status is: posted for load restriction.

It carries about 438 vehicles a day, projected to reach 481 by 2040. The structure is 129 ft (39.3 m) long and 14 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

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CarriesSmithridge Bridge
CrossesPetit Caillou Bayou
Location0001 Log MI from in
RouteCounty Highway 0
CountyTerrebonne Parish
StateLouisiana
Coordinates29.49319, -90.57392
Functional classRural 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
Deck7 GoodSome minor problems.
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 protection7 GoodSome minor problems.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating6.4 US tons
Inventory rating5 US tons

Structure

Structure typeMovable - Swing
MaterialSteel
DeckWood or timber
Main spans1
Design loadHS 20
Structure length129 ft (39.3 m)
Longest span129 ft (39.3 m)
Deck width14 ft (4.3 m)
Roadway width14 ft (4.2 m)
Vertical clearance over deck13 ft (4.1 m)

Traffic and service

Average daily traffic438 (2020)
Projected traffic481 by 2040
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusEligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$433,000
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was Smithridge Bridge over Petit Caillou Bayou built?

It was built in 1968, making it 57 years old in 2025.

What condition is Smithridge Bridge over Petit Caillou 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 June 2023.

How much traffic does Smithridge Bridge over Petit Caillou Bayou carry?

About 438 vehicles per day (2020 count).

How long is Smithridge Bridge over Petit Caillou Bayou?

The structure is 129 ft (39.3 m) long with a longest span of 129 ft (39.3 m) and a deck 14 ft wide.

Who owns Smithridge Bridge over Petit Caillou Bayou?

It is owned by the County Highway Agency.