US Bridges

LA0021 over Bogue Chitto River

Good

St. Tammany Parish, Louisiana · LA0021 · Structure no. 625200300201612

Built
1974
51 years old
Condition
Good
inspected November 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
1,422 ft
26 main spans
Daily traffic
7,481
2021 count
Owner
State
State Highway Agency

About this bridge

LA0021 over Bogue Chitto River is a prestressed concrete stringer/multi-beam or girder carrying LA0021 over Bogue Chitto River in St. Tammany Parish, Louisiana. It was built in 1974, so it is 51 years old, older than the Louisiana average of 43 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 7,481 vehicles a day, roughly 12% of them trucks, projected to reach 8,229 by 2041. The structure is 1,422 ft (433.4 m) long and 43 ft wide. If it were closed, the detour would be 34.2 mi (55 km).

CarriesLA0021
CrossesBogue Chitto River
LocationLA0021
RouteState Highway 21
Coordinates30.63188, -89.8966
Functional classRural Principal Arterial - Other

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation7: Better than 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 rating79 US tons
Inventory rating39 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans26
Design loadHS 20
Structure length1,422 ft (433.4 m)
Longest span80 ft (24.4 m)
Deck width43 ft (13.1 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,481 (2021)
Projected traffic8,229 by 2041
Trucks12%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed34.2 mi (55 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was LA0021 over Bogue Chitto River built?

It was built in 1974, making it 51 years old in 2025.

What condition is LA0021 over Bogue Chitto River in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in November 2023.

How much traffic does LA0021 over Bogue Chitto River carry?

About 7,481 vehicles per day (2021 count), of which roughly 12% are trucks.

How long is LA0021 over Bogue Chitto River?

The structure is 1,422 ft (433.4 m) long with a longest span of 80 ft (24.4 m) and a deck 43 ft wide.

Who owns LA0021 over Bogue Chitto River?

It is owned by the State Highway Agency.