US Bridges

LA0091 over Bayou Jonas

Poor

Acadia Parish, Louisiana · 1.66 MI W of LA 1120 · Structure no. 030102110106361

Built
1979
46 years old
Condition
Poor
inspected March 2023
Type
Slab
Concrete
Length
114 ft
6 main spans
Daily traffic
1,617
2021 count
Owner
State
State Highway Agency

About this bridge

LA0091 over Bayou Jonas is a concrete slab carrying LA0091 over Bayou Jonas in Acadia Parish, Louisiana. It was built in 1979, so it is 46 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.

It carries about 1,617 vehicles a day, roughly 13% of them trucks, projected to reach 1,778 by 2041. The structure is 114 ft (34.7 m) long and 43 ft wide. If it were closed, the detour would be 11.2 mi (18 km).

Location

Open in Google Maps
CarriesLA0091
CrossesBayou Jonas
Location1.66 MI W of LA 1120
RouteState Highway 91
CountyAcadia Parish
StateLouisiana
Coordinates30.23656, -92.4919
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating34.6 US tons
Inventory rating26.8 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans6
Design loadHS 20
Structure length114 ft (34.7 m)
Longest span19 ft (5.8 m)
Deck width43 ft (13.2 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,617 (2021)
Projected traffic1,778 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 LA0091 over Bayou Jonas built?

It was built in 1979, making it 46 years old in 2025.

What condition is LA0091 over Bayou Jonas 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 March 2023.

How much traffic does LA0091 over Bayou Jonas carry?

About 1,617 vehicles per day (2021 count), of which roughly 13% are trucks.

How long is LA0091 over Bayou Jonas?

The structure is 114 ft (34.7 m) long with a longest span of 19 ft (5.8 m) and a deck 43 ft wide.

Who owns LA0091 over Bayou Jonas?

It is owned by the State Highway Agency.