US Bridges

S-12-46 over I-77

Fair

Chester County, South Carolina · 4.1 MI N Richburg · Structure no. 000000000007220

Built
1979
46 years old
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
334 ft
2 main spans
Daily traffic
200
2023 count
Owner
State
State Highway Agency

About this bridge

S-12-46 over I-77 is a steel continuous stringer/multi-beam or girder carrying S-12-46 over I-77 in Chester County, South Carolina. It was built in 1979, so it is 46 years old, younger 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 6 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 200 vehicles a day, projected to reach 256 by 2043. The structure is 334 ft (101.8 m) long and 37 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesS-12-46
CrossesI-77
Location4.1 MI N Richburg
RouteState Highway 46
Coordinates34.77293, -81.03771
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating31.1 US tons
Inventory rating23.9 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2 (+2 approach)
Design loadHS 15
Structure length334 ft (101.8 m)
Longest span126 ft (38.4 m)
Deck width37 ft (11.4 m)
Roadway width34 ft (10.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic200 (2023)
Projected traffic256 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed5 mi (8 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was S-12-46 over I-77 built?

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

What condition is S-12-46 over I-77 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 March 2023.

How much traffic does S-12-46 over I-77 carry?

About 200 vehicles per day (2023 count).

How long is S-12-46 over I-77?

The structure is 334 ft (101.8 m) long with a longest span of 126 ft (38.4 m) and a deck 37 ft wide.

Who owns S-12-46 over I-77?

It is owned by the State Highway Agency.