S-20-21 over I-77
FairFairfield County, South Carolina · 6MI SE Winnsboro · Structure no. 000000000007254
- Built
- 1979
- 46 years old
- Condition
- Fair
- inspected May 2023
- Type
- Frame
- Steel Continuous
- Length
- 332 ft
- 5 main spans
- Daily traffic
- 125
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
S-20-21 over I-77 is a steel continuous frame carrying S-20-21 over I-77 in Fairfield 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 125 vehicles a day, roughly 5% of them trucks, projected to reach 160 by 2043. The structure is 332 ft (101.2 m) long and 37 ft wide. If it were closed, the detour would be 16.2 mi (26 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was S-20-21 over I-77 built?
It was built in 1979, making it 46 years old in 2025.
What condition is S-20-21 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 May 2023.
How much traffic does S-20-21 over I-77 carry?
About 125 vehicles per day (2023 count), of which roughly 5% are trucks.
How long is S-20-21 over I-77?
The structure is 332 ft (101.2 m) long with a longest span of 105 ft (32 m) and a deck 37 ft wide.
Who owns S-20-21 over I-77?
It is owned by the State Highway Agency.