US Bridges

LA1105 over Grand Coulee

Fair

Acadia Parish, Louisiana · 0.7 MI North of LA 370 · Structure no. 030108012900701

Built
1971
54 years old
Condition
Fair
inspected February 2023
Type
Slab
Concrete
Length
38 ft
2 main spans
Daily traffic
608
2021 count
Owner
State
State Highway Agency

About this bridge

LA1105 over Grand Coulee is a concrete slab carrying LA1105 over Grand Coulee in Acadia 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 fair condition with a lowest component rating of 5 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 608 vehicles a day, roughly 13% of them trucks, projected to reach 668 by 2041. The structure is 38 ft (11.6 m) long and 31 ft wide. If it were closed, the detour would be 11.2 mi (18 km).

Location

Open in Google Maps
CarriesLA1105
CrossesGrand Coulee
Location0.7 MI North of LA 370
RouteState Highway 1105
CountyAcadia Parish
StateLouisiana
Coordinates30.43917, -92.31274
Functional classRural Major 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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being 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 rating70 US tons
Inventory rating42 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans2
Design loadHS 20
Structure length38 ft (11.6 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 traffic608 (2021)
Projected traffic668 by 2041
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.2 mi (18 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was LA1105 over Grand Coulee built?

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

What condition is LA1105 over Grand 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 February 2023.

How much traffic does LA1105 over Grand Coulee carry?

About 608 vehicles per day (2021 count), of which roughly 13% are trucks.

How long is LA1105 over Grand Coulee?

The structure is 38 ft (11.6 m) long with a longest span of 19 ft (5.8 m) and a deck 31 ft wide.

Who owns LA1105 over Grand Coulee?

It is owned by the State Highway Agency.