US 21 over Harbor River
GoodBeaufort County, South Carolina · 12.5 MI SE of Beaurfort · Structure no. 000000000010538
- Built
- 2021
- 4 years old
- Condition
- Good
- inspected April 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete Continuous
- Length
- 3,340 ft
- 20 main spans
- Daily traffic
- 2,600
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
US 21 over Harbor River is a prestressed concrete continuous stringer/multi-beam or girder carrying US 21 over Harbor River in Beaufort County, South Carolina. It was built in 2021, so it is 4 years old, younger than the South Carolina average of 48 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 2,600 vehicles a day, roughly 8% of them trucks, projected to reach 4,134 by 2043. The structure is 3,340 ft (1,018 m) long and 47 ft wide. If it were closed, the detour would be 3.7 mi (6 km).
Location
Open in Google MapsCondition and inspection
All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 8 Very Good | No problems noted. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 21 over Harbor River built?
It was built in 2021, making it 4 years old in 2025.
What condition is US 21 over Harbor River in?
The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in April 2023.
How much traffic does US 21 over Harbor River carry?
About 2,600 vehicles per day (2023 count), of which roughly 8% are trucks.
How long is US 21 over Harbor River?
The structure is 3,340 ft (1,018 m) long with a longest span of 168 ft (51.2 m) and a deck 47 ft wide.
Who owns US 21 over Harbor River?
It is owned by the State Highway Agency.