US Bridges

I0059 over Yellow Bayou

Fair

St. Tammany Parish, Louisiana · I0059 · Structure no. 625204530107021

Built
1962
63 years old, rebuilt 1987
Condition
Fair
inspected August 2023
Type
Slab
Concrete
Length
320 ft
16 main spans
Daily traffic
36,841
2021 count
Owner
State
State Highway Agency

About this bridge

I0059 over Yellow Bayou is a concrete slab carrying I0059 over Yellow Bayou in St. Tammany Parish, Louisiana. It was built in 1962 and reconstructed in 1987, so it is 63 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 36,841 vehicles a day, roughly 25% of them trucks, projected to reach 40,525 by 2041. The structure is 320 ft (97.5 m) long and 43 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI0059
CrossesYellow Bayou
LocationI0059
RouteInterstate 59
CountySt. Tammany Parish
StateLouisiana
Coordinates30.40314, -89.7264
Functional classRural Principal Arterial - Interstate

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 protection8 Very GoodNo problems noted.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating63.1 US tons
Inventory rating38 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans16
Design loadHS 20
Structure length320 ft (97.5 m)
Longest span20 ft (6.1 m)
Deck width43 ft (13 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic36,841 (2021)
Projected traffic40,525 by 2041
Trucks25%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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 I0059 over Yellow Bayou built?

It was built in 1962, making it 63 years old in 2025. It was reconstructed in 1987.

What condition is I0059 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 August 2023.

How much traffic does I0059 over Yellow Bayou carry?

About 36,841 vehicles per day (2021 count), of which roughly 25% are trucks.

How long is I0059 over Yellow Bayou?

The structure is 320 ft (97.5 m) long with a longest span of 20 ft (6.1 m) and a deck 43 ft wide.

Who owns I0059 over Yellow Bayou?

It is owned by the State Highway Agency.