US Bridges

LA0040 over Natalbany River

PoorPosted for load

Tangipahoa Parish, Louisiana · 0.5 M W of I-55 · Structure no. 625304150201671

Built
1971
54 years old
Condition
Poor
inspected April 2023
Type
Slab
Concrete
Length
172 ft
8 main spans
Daily traffic
913
2021 count
Owner
State
State Highway Agency

About this bridge

LA0040 over Natalbany River is a concrete slab carrying LA0040 over Natalbany River in Tangipahoa Parish, Louisiana. It was built in 1971, so it is 54 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 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. Its operating status is: posted for load restriction.

It carries about 913 vehicles a day, roughly 12% of them trucks, projected to reach 1,004 by 2041. The structure is 172 ft (52.4 m) long and 31 ft wide.

Location

Open in Google Maps
CarriesLA0040
CrossesNatalbany River
Location0.5 M W of I-55
RouteState Highway 40
CountyTangipahoa Parish
StateLouisiana
Coordinates30.64294, -90.5393
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.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourScour critical; foundations unstable for calculated scour conditions
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 adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating27.9 US tons
Inventory rating21.8 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans8
Design loadHS 20
Structure length172 ft (52.4 m)
Longest span19 ft (5.8 m)
Deck width31 ft (9.4 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic913 (2021)
Projected traffic1,004 by 2041
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
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$787,000
NavigationNo navigation control on waterway

Frequently asked questions

When was LA0040 over Natalbany River built?

It was built in 1971, making it 54 years old in 2025.

What condition is LA0040 over Natalbany River 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 April 2023.

How much traffic does LA0040 over Natalbany River carry?

About 913 vehicles per day (2021 count), of which roughly 12% are trucks.

How long is LA0040 over Natalbany River?

The structure is 172 ft (52.4 m) long with a longest span of 19 ft (5.8 m) and a deck 31 ft wide.

Who owns LA0040 over Natalbany River?

It is owned by the State Highway Agency.