US 521 over Ox Swamp
FairWilliamsburg County, South Carolina · 10.0 MI SE of Kingstree · Structure no. 000000000000585
- Built
- 1931
- 94 years old, rebuilt 1966
- Condition
- Fair
- inspected November 2024
- Type
- Tee Beam
- Concrete
- Length
- 150 ft
- 6 main spans
- Daily traffic
- 3,100
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
US 521 over Ox Swamp is a concrete tee beam carrying US 521 over Ox Swamp in Williamsburg County, South Carolina. It was built in 1931 and reconstructed in 1966, 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 3,100 vehicles a day, roughly 16% of them trucks, projected to reach 5,394 by 2043. The structure is 150 ft (45.7 m) long and 47 ft wide. If it were closed, the detour would be 3.1 mi (5 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 521 over Ox Swamp built?
It was built in 1931, making it 94 years old in 2025. It was reconstructed in 1966.
What condition is US 521 over Ox 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 November 2024.
How much traffic does US 521 over Ox Swamp carry?
About 3,100 vehicles per day (2023 count), of which roughly 16% are trucks.
How long is US 521 over Ox 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 US 521 over Ox Swamp?
It is owned by the State Highway Agency.