US 521 over Thorntree Swamp

Fair Condition95 years old2,200 vehicles/day

Location

StateSouth Carolina
CountyWilliamsburg
Location5.3 Mi S Of Kingstree
CarriesUS 521
CrossesThorntree Swamp
Coordinates33.58770, -79.83714

Condition Ratings

Overall ConditionFair
Channel/Waterway6 (Satisfactory)
Culvert6 (Satisfactory)
Scour Critical8 — Stable, low risk

Physical Characteristics

MaterialConcrete
DesignCulvert
Total Length34.1 ft (10.4 m)
Max Span9.8 ft (3 m)
Deck Width55.1 ft (16.8 m)
Deck Area174.7 sq m
Main Spans3
Year Built1931 (reconstructed 1965)

Traffic

Avg Daily Traffic2,200 (2023)
Truck Traffic22%
Lanes On Bridge2

Inspection & Ownership

Last Inspection623
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Structure Number000000000000587

Nearby Bridges

S-45-143 over Thorntree Swamp 0.3 mi Poor S-45-453 over Thorntree Swamp 0.6 mi Fair US 521 over S.c.l. Railroad 1.1 mi Fair Sc 377 over Black River 1.1 mi Good Sc 377 over Black River Swamp (1) 1.3 mi Good US 521 over Stony Run 1.3 mi Fair Sc 377 over Black River Swamp (2) 1.4 mi Good Sc 377 over Black River Swamp (3) 1.6 mi Good S-45-570 over Thorntree Swamp 2.0 mi Good S-45-142 over Boggy Swamp 3.2 mi Good