US Bridges

LA0129 over Ross Bayou

Poor

Concordia Parish, Louisiana · 1.03 MI North of LA 565 · Structure no. 581503550101031

Built
2000
25 years old
Condition
Poor
inspected February 2024
Type
Slab
Concrete
Length
116 ft
6 main spans
Daily traffic
1,684
2021 count
Owner
State
State Highway Agency

About this bridge

LA0129 over Ross Bayou is a concrete slab carrying LA0129 over Ross Bayou in Concordia Parish, Louisiana. It was built in 2000, so it is 25 years old, younger 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 4 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 1,684 vehicles a day, roughly 21% of them trucks, projected to reach 1,852 by 2041. The structure is 116 ft (35.4 m) long and 35 ft wide. If it were closed, the detour would be 11.8 mi (19 km).

Location

Open in Google Maps
CarriesLA0129
CrossesRoss Bayou
Location1.03 MI North of LA 565
RouteState Highway 129
CountyConcordia Parish
StateLouisiana
Coordinates31.52757, -91.7076
Functional classRural Major Collector

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
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionFebruary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating43.5 US tons
Inventory rating33.6 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans6
Design loadHS 20
Structure length116 ft (35.4 m)
Longest span19 ft (5.8 m)
Deck width35 ft (10.6 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,684 (2021)
Projected traffic1,852 by 2041
Trucks21%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.8 mi (19 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was LA0129 over Ross Bayou built?

It was built in 2000, making it 25 years old in 2025.

What condition is LA0129 over Ross Bayou 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 February 2024.

How much traffic does LA0129 over Ross Bayou carry?

About 1,684 vehicles per day (2021 count), of which roughly 21% are trucks.

How long is LA0129 over Ross Bayou?

The structure is 116 ft (35.4 m) long with a longest span of 19 ft (5.8 m) and a deck 35 ft wide.

Who owns LA0129 over Ross Bayou?

It is owned by the State Highway Agency.