US Bridges

LA0001 over Bayou Plaquemine

Poor

Iberville Parish, Louisiana · 0.20 MI SE of LA 77 · Structure no. 612400500614452

Built
1950
75 years old
Condition
Poor
inspected August 2024
Type
Truss - Thru
Steel
Length
1,259 ft
3 main spans
Daily traffic
10,843
2021 count
Owner
State
State Highway Agency

About this bridge

LA0001 over Bayou Plaquemine is a steel truss - thru carrying LA0001 over Bayou Plaquemine in Iberville Parish, Louisiana. It was built in 1950, so it is 75 years old, older than the Louisiana average of 43 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 3 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 10,843 vehicles a day, roughly 9% of them trucks, projected to reach 11,927 by 2041. The structure is 1,259 ft (383.7 m) long and 38 ft wide. If it were closed, the detour would be 13 mi (21 km).

Location

Open in Google Maps
CarriesLA0001
CrossesBayou Plaquemine
Location0.20 MI SE of LA 77
RouteState Highway 1
CountyIberville Parish
StateLouisiana
Coordinates30.2937, -91.23874
Functional classUrban Other Principal Arterial

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating19.3 US tons
Inventory rating15 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans3 (+48 approach)
Design loadHS 20
Structure length1,259 ft (383.7 m)
Longest span150 ft (45.7 m)
Deck width38 ft (11.7 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deck17 ft (5.2 m)

Traffic and service

Average daily traffic10,843 (2021)
Projected traffic11,927 by 2041
Trucks9%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed13 mi (21 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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$4.9 million
NavigationNo navigation control on waterway

Frequently asked questions

When was LA0001 over Bayou Plaquemine built?

It was built in 1950, making it 75 years old in 2025.

What condition is LA0001 over Bayou Plaquemine in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in August 2024.

How much traffic does LA0001 over Bayou Plaquemine carry?

About 10,843 vehicles per day (2021 count), of which roughly 9% are trucks.

How long is LA0001 over Bayou Plaquemine?

The structure is 1,259 ft (383.7 m) long with a longest span of 150 ft (45.7 m) and a deck 38 ft wide.

Who owns LA0001 over Bayou Plaquemine?

It is owned by the State Highway Agency.