Md 478 over Br of Potomac River
GoodFrederick County, Maryland · 1.78 MI S. East of Md 180 · Structure no. 100000100089010
- Built
- 2019
- 6 years old
- Condition
- Good
- inspected January 2024
- Type
- Slab
- Prestressed Concrete
- Length
- 58 ft
- 1 main span
- Daily traffic
- 2,471
- 2009 count
- Owner
- State
- State Highway Agency
About this bridge
Md 478 over Br of Potomac River is a prestressed concrete slab carrying Md 478 over Br of Potomac River in Frederick County, Maryland. It was built in 2019, so it is 6 years old, younger than the Maryland average of 52.6 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 2,471 vehicles a day, roughly 8% of them trucks, projected to reach 3,506 by 2026. The structure is 58 ft (17.8 m) long and 42 ft wide. If it were closed, the detour would be 8.1 mi (13 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 | 8 Very Good | No problems noted. |
| Superstructure | 8 Very Good | No problems noted. |
| Substructure | 9 Excellent | 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 Md 478 over Br of Potomac River built?
It was built in 2019, making it 6 years old in 2025.
What condition is Md 478 over Br of Potomac 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 January 2024.
How much traffic does Md 478 over Br of Potomac River carry?
About 2,471 vehicles per day (2009 count), of which roughly 8% are trucks.
How long is Md 478 over Br of Potomac River?
The structure is 58 ft (17.8 m) long with a longest span of 55 ft (16.8 m) and a deck 42 ft wide.
Who owns Md 478 over Br of Potomac River?
It is owned by the State Highway Agency.