US 401 over I-20
FairDarlington County, South Carolina · 3MI N of Lamar · Structure no. 000000000006461
- Built
- 1974
- 51 years old
- Condition
- Fair
- inspected January 2024
- Type
- Stringer/Multi-beam or Girder
- Steel Continuous
- Length
- 294 ft
- 4 main spans
- Daily traffic
- 3,200
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
US 401 over I-20 is a steel continuous stringer/multi-beam or girder carrying US 401 over I-20 in Darlington County, South Carolina. It was built in 1974, so it is 51 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 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 3,200 vehicles a day, roughly 15% of them trucks, projected to reach 2,464 by 2043. The structure is 294 ft (89.6 m) long and 63 ft wide.
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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 401 over I-20 built?
It was built in 1974, making it 51 years old in 2025.
What condition is US 401 over I-20 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 January 2024.
How much traffic does US 401 over I-20 carry?
About 3,200 vehicles per day (2023 count), of which roughly 15% are trucks.
How long is US 401 over I-20?
The structure is 294 ft (89.6 m) long with a longest span of 105 ft (32 m) and a deck 63 ft wide.
Who owns US 401 over I-20?
It is owned by the State Highway Agency.