US Bridges

Duchamp RD over Lasalle Coulee

Fair

St. Martin Parish, Louisiana · 1.1 Mi. NE of LA 182 · Structure no. 035030067915421

Built
1966
59 years old
Condition
Fair
inspected October 2024
Type
Slab
Concrete
Length
57 ft
3 main spans
Daily traffic
1,388
2020 count
Owner
County
County Highway Agency

About this bridge

Duchamp RD over Lasalle Coulee is a concrete slab carrying Duchamp RD over Lasalle Coulee in St. Martin Parish, Louisiana. It was built in 1966, so it is 59 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 1,388 vehicles a day, projected to reach 1,526 by 2040. The structure is 57 ft (17.4 m) long and 26 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesDuchamp RD
CrossesLasalle Coulee
Location1.1 Mi. NE of LA 182
RouteCounty Highway 0
CountySt. Martin Parish
StateLouisiana
Coordinates30.11224, -91.90395
Functional classRural Local

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.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating25.4 US tons
Inventory rating19.6 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans3
Design loadHS 20
Structure length57 ft (17.4 m)
Longest span19 ft (5.8 m)
Deck width26 ft (8 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,388 (2020)
Projected traffic1,526 by 2040
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Duchamp RD over Lasalle Coulee built?

It was built in 1966, making it 59 years old in 2025.

What condition is Duchamp RD over Lasalle Coulee 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 October 2024.

How much traffic does Duchamp RD over Lasalle Coulee carry?

About 1,388 vehicles per day (2020 count).

How long is Duchamp RD over Lasalle Coulee?

The structure is 57 ft (17.4 m) long with a longest span of 19 ft (5.8 m) and a deck 26 ft wide.

Who owns Duchamp RD over Lasalle Coulee?

It is owned by the County Highway Agency.