S-21-105 over Big Swamp
FairFlorence County, South Carolina · 1.5MI N Hyman · Structure no. 000000000009004
- Built
- 1996
- 29 years old
- Condition
- Fair
- inspected March 2023
- Type
- Slab
- Concrete Continuous
- Length
- 74 ft
- 3 main spans
- Daily traffic
- 650
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
S-21-105 over Big Swamp is a concrete continuous slab carrying S-21-105 over Big Swamp in Florence County, South Carolina. It was built in 1996, so it is 29 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 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 650 vehicles a day, roughly 14% of them trucks, projected to reach 949 by 2043. The structure is 74 ft (22.6 m) long and 37 ft wide. If it were closed, the detour would be 1.9 mi (3 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 | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Channel and channel protection | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was S-21-105 over Big Swamp built?
It was built in 1996, making it 29 years old in 2025.
What condition is S-21-105 over Big 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 March 2023.
How much traffic does S-21-105 over Big Swamp carry?
About 650 vehicles per day (2023 count), of which roughly 14% are trucks.
How long is S-21-105 over Big Swamp?
The structure is 74 ft (22.6 m) long with a longest span of 30 ft (9.1 m) and a deck 37 ft wide.
Who owns S-21-105 over Big Swamp?
It is owned by the State Highway Agency.