US 521 over Mill Branch
FairClarendon County, South Carolina · 3MI N of Manning · Structure no. 000000000001611
- Built
- 1949
- 76 years old, rebuilt 2005
- Condition
- Fair
- inspected January 2024
- Type
- Culvert
- Concrete
- Length
- 25 ft
- 2 main spans
- Daily traffic
- 7,700
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
US 521 over Mill Branch is a concrete culvert carrying US 521 over Mill Branch in Clarendon County, South Carolina. It was built in 1949 and reconstructed in 2005, so it is 76 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 7,700 vehicles a day, roughly 20% of them trucks, projected to reach 13,398 by 2043. The structure is 25 ft (7.6 m) long and 146 ft wide. If it were closed, the detour would be 1.2 mi (2 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 |
|---|---|---|
| Channel and channel protection | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Culvert | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 521 over Mill Branch built?
It was built in 1949, making it 76 years old in 2025. It was reconstructed in 2005.
What condition is US 521 over Mill Branch 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 521 over Mill Branch carry?
About 7,700 vehicles per day (2023 count), of which roughly 20% are trucks.
How long is US 521 over Mill Branch?
The structure is 25 ft (7.6 m) long with a longest span of 12 ft (3.7 m) and a deck 146 ft wide.
Who owns US 521 over Mill Branch?
It is owned by the State Highway Agency.