US Bridges

Longswitch Road over Six Mile Bayou

Fair

Washington County, Mississippi · Sec 2 T18N R 6W B · Structure no. SA7600000000211

Built
1961
64 years old, rebuilt 2016
Condition
Fair
inspected January 2024
Type
Channel Beam
Concrete
Length
76 ft
4 main spans
Daily traffic
50
2023 count
Owner
County
County Highway Agency

About this bridge

Longswitch Road over Six Mile Bayou is a concrete channel beam carrying Longswitch Road over Six Mile Bayou in Washington County, Mississippi. It was built in 1961 and reconstructed in 2016, so it is 64 years old, older than the Mississippi average of 38.9 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 50 vehicles a day, roughly 8% of them trucks, projected to reach 70 by 2043. The structure is 76 ft (23.2 m) long and 31 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesLongswitch Road
CrossesSix Mile Bayou
LocationSec 2 T18N R 6W B
RouteCounty Highway 824
CountyWashington County
StateMississippi
Coordinates33.44447, -90.7874
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
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.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating57.1 US tons
Inventory rating34.2 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans4
Design loadH 15
Structure length76 ft (23.2 m)
Longest span19 ft (5.8 m)
Deck width31 ft (9.4 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2023)
Projected traffic70 by 2043
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$926,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Longswitch Road over Six Mile Bayou built?

It was built in 1961, making it 64 years old in 2025. It was reconstructed in 2016.

What condition is Longswitch Road over Six Mile Bayou 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 January 2024.

How much traffic does Longswitch Road over Six Mile Bayou carry?

About 50 vehicles per day (2023 count), of which roughly 8% are trucks.

How long is Longswitch Road over Six Mile Bayou?

The structure is 76 ft (23.2 m) long with a longest span of 19 ft (5.8 m) and a deck 31 ft wide.

Who owns Longswitch Road over Six Mile Bayou?

It is owned by the County Highway Agency.