US Bridges

LA0175 over Bayou San Miguel Relief

Fair

Sabine Parish, Louisiana · 1.94 M N of N Jct. LA 120 · Structure no. 084300350201941

Built
1934
91 years old
Condition
Fair
inspected August 2024
Type
Tee Beam
Concrete
Length
92 ft
3 main spans
Daily traffic
1,587
2021 count
Owner
State
State Highway Agency

About this bridge

LA0175 over Bayou San Miguel Relief is a concrete tee beam carrying LA0175 over Bayou San Miguel Relief in Sabine Parish, Louisiana. It was built in 1934, so it is 91 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 1,587 vehicles a day, roughly 14% of them trucks, projected to reach 1,745 by 2041. The structure is 92 ft (28 m) long and 29 ft wide. If it were closed, the detour would be 21.7 mi (35 km).

Location

Open in Google Maps
CarriesLA0175
CrossesBayou San Miguel Relief
Location1.94 M N of N Jct. LA 120
RouteState Highway 175
CountySabine Parish
StateLouisiana
Coordinates31.74263, -93.5093
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating33.6 US tons
Inventory rating26.1 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length92 ft (28 m)
Longest span30 ft (9.1 m)
Deck width29 ft (8.7 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,587 (2021)
Projected traffic1,745 by 2041
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesRelief for waterway
Detour if closed21.7 mi (35 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 LA0175 over Bayou San Miguel Relief built?

It was built in 1934, making it 91 years old in 2025.

What condition is LA0175 over Bayou San Miguel Relief 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 August 2024.

How much traffic does LA0175 over Bayou San Miguel Relief carry?

About 1,587 vehicles per day (2021 count), of which roughly 14% are trucks.

How long is LA0175 over Bayou San Miguel Relief?

The structure is 92 ft (28 m) long with a longest span of 30 ft (9.1 m) and a deck 29 ft wide.

Who owns LA0175 over Bayou San Miguel Relief?

It is owned by the State Highway Agency.