Seaport Causeway over Biscayne Bay
FairClosed to trafficMiami-Dade County, Florida · Entrance to Port of Miami · Structure no. 874998
- Built
- 1964
- 61 years old
- Condition
- Fair
- inspected January 2024
- Type
- Movable - Bascule
- Steel
- Length
- 2,239 ft
- 1 main span
- Daily traffic
- 1
- 2024 count
- Owner
- County
- County Highway Agency
About this bridge
Seaport Causeway over Biscayne Bay is a steel movable - bascule carrying Seaport Causeway over Biscayne Bay in Miami-Dade County, Florida. It was built in 1964, so it is 61 years old, older than the Florida average of 41.3 years.
The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: closed to all traffic.
It carries about 1 vehicles a day, roughly 50% of them trucks, projected to reach 24 by 2042. The structure is 2,239 ft (682.4 m) long and 37 ft wide. If it were closed, the detour would be 0.6 mi (1 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Substructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Channel and channel protection | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Seaport Causeway over Biscayne Bay built?
It was built in 1964, making it 61 years old in 2025.
What condition is Seaport Causeway over Biscayne Bay 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 Seaport Causeway over Biscayne Bay carry?
About 1 vehicles per day (2024 count), of which roughly 50% are trucks.
How long is Seaport Causeway over Biscayne Bay?
The structure is 2,239 ft (682.4 m) long with a longest span of 106 ft (32.3 m) and a deck 37 ft wide.
Who owns Seaport Causeway over Biscayne Bay?
It is owned by the County Highway Agency.