US Bridges

LA0317 over Yellow Bayou

Fair

St. Mary Parish, Louisiana · 0.5 Mi. North of US 90 · Structure no. 035102430206521

Built
1950
75 years old
Condition
Fair
inspected May 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
80 ft
3 main spans
Daily traffic
2,330
2021 count
Owner
State
State Highway Agency

About this bridge

LA0317 over Yellow Bayou is a steel stringer/multi-beam or girder carrying LA0317 over Yellow Bayou in St. Mary 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 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 2,330 vehicles a day, roughly 9% of them trucks, projected to reach 2,563 by 2041. The structure is 80 ft (24.4 m) long and 29 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesLA0317
CrossesYellow Bayou
Location0.5 Mi. North of US 90
RouteState Highway 317
CountySt. Mary Parish
StateLouisiana
Coordinates29.75021, -91.4313
Functional classUrban Collector

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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no 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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46 US tons
Inventory rating28 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadH 10
Structure length80 ft (24.4 m)
Longest span30 ft (9.1 m)
Deck width29 ft (8.8 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,330 (2021)
Projected traffic2,563 by 2041
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$412,000
NavigationNo navigation control on waterway

Frequently asked questions

When was LA0317 over Yellow Bayou built?

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

What condition is LA0317 over Yellow 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 LA0317 over Yellow Bayou carry?

About 2,330 vehicles per day (2021 count), of which roughly 9% are trucks.

How long is LA0317 over Yellow Bayou?

The structure is 80 ft (24.4 m) long with a longest span of 30 ft (9.1 m) and a deck 29 ft wide.

Who owns LA0317 over Yellow Bayou?

It is owned by the State Highway Agency.