US Bridges

Sc 9 over Mitchell Swamp

Fair

Horry County, South Carolina · 6.5MI NW of Loris · Structure no. 000000000000550

Built
1931
94 years old, rebuilt 1967
Condition
Fair
inspected August 2024
Type
Tee Beam
Concrete
Length
150 ft
6 main spans
Daily traffic
2,400
2023 count
Owner
State
State Highway Agency

About this bridge

Sc 9 over Mitchell Swamp is a concrete tee beam carrying Sc 9 over Mitchell Swamp in Horry County, South Carolina. It was built in 1931 and reconstructed in 1967, so it is 94 years old, older than the South Carolina average of 48 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 2,400 vehicles a day, roughly 6% of them trucks, projected to reach 3,504 by 2043. The structure is 150 ft (45.7 m) long and 47 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesSc 9
CrossesMitchell Swamp
Location6.5MI NW of Loris
RouteState Highway 9
CountyHorry County
StateSouth Carolina
Coordinates34.11434, -78.97762
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating52.5 US tons
Inventory rating31.4 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans6
Design loadH 15
Structure length150 ft (45.7 m)
Longest span25 ft (7.6 m)
Deck width47 ft (14.3 m)
Roadway width43 ft (13 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,400 (2023)
Projected traffic3,504 by 2043
Trucks6%
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

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 Sc 9 over Mitchell Swamp built?

It was built in 1931, making it 94 years old in 2025. It was reconstructed in 1967.

What condition is Sc 9 over Mitchell Swamp 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 Sc 9 over Mitchell Swamp carry?

About 2,400 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is Sc 9 over Mitchell Swamp?

The structure is 150 ft (45.7 m) long with a longest span of 25 ft (7.6 m) and a deck 47 ft wide.

Who owns Sc 9 over Mitchell Swamp?

It is owned by the State Highway Agency.