US Bridges

US 378 over Mountain Creek

Fair

Edgefield County, South Carolina · 10.9 MI NW of Edgefield · Structure no. 000000000001033

Built
1940
85 years old, rebuilt 1959
Condition
Fair
inspected January 2024
Type
Tee Beam
Concrete
Length
125 ft
5 main spans
Daily traffic
1,050
2023 count
Owner
State
State Highway Agency

About this bridge

US 378 over Mountain Creek is a concrete tee beam carrying US 378 over Mountain Creek in Edgefield County, South Carolina. It was built in 1940 and reconstructed in 1959, so it is 85 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 1,050 vehicles a day, roughly 20% of them trucks, projected to reach 1,670 by 2043. The structure is 125 ft (38.1 m) long and 31 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

Location

Open in Google Maps
CarriesUS 378
CrossesMountain Creek
Location10.9 MI NW of Edgefield
RouteU.S. Route 378
CountyEdgefield County
StateSouth Carolina
Coordinates33.92861, -82.02469
Functional classRural Minor Arterial

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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating28.9 US tons
Inventory rating17.2 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans5
Design loadH 15
Structure length125 ft (38.1 m)
Longest span25 ft (7.6 m)
Deck width31 ft (9.6 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,050 (2023)
Projected traffic1,670 by 2043
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 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 proposedWidening with deck rehabilitation or replacement
Estimated improvement cost$260,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 378 over Mountain Creek built?

It was built in 1940, making it 85 years old in 2025. It was reconstructed in 1959.

What condition is US 378 over Mountain Creek 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 US 378 over Mountain Creek carry?

About 1,050 vehicles per day (2023 count), of which roughly 20% are trucks.

How long is US 378 over Mountain Creek?

The structure is 125 ft (38.1 m) long with a longest span of 25 ft (7.6 m) and a deck 31 ft wide.

Who owns US 378 over Mountain Creek?

It is owned by the State Highway Agency.