Old US 51 over Pass Manchac
PoorPosted for loadTangipahoa Parish, Louisiana · Pass Manchac · Structure no. 625304529000003
- Built
- 1957
- 68 years old
- Condition
- Poor
- inspected December 2024
- Type
- Stringer/Multi-beam or Girder
- Steel Continuous
- Length
- 3,012 ft
- 1 main span
- Daily traffic
- 4,107
- 2021 count
- Owner
- State
- State Highway Agency
About this bridge
Old US 51 over Pass Manchac is a steel continuous stringer/multi-beam or girder carrying Old US 51 over Pass Manchac in Tangipahoa Parish, Louisiana. It was built in 1957, so it is 68 years old, older than the Louisiana average of 43 years.
The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for load restriction.
It carries about 4,107 vehicles a day, roughly 12% of them trucks, projected to reach 4,517 by 2041. The structure is 3,012 ft (918.1 m) long and 33 ft wide. If it were closed, the detour would be 98.8 mi (159 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 4 Poor | Advanced section loss, deterioration, 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 | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Old US 51 over Pass Manchac built?
It was built in 1957, making it 68 years old in 2025.
What condition is Old US 51 over Pass Manchac in?
The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in December 2024.
How much traffic does Old US 51 over Pass Manchac carry?
About 4,107 vehicles per day (2021 count), of which roughly 12% are trucks.
How long is Old US 51 over Pass Manchac?
The structure is 3,012 ft (918.1 m) long with a longest span of 285 ft (86.9 m) and a deck 33 ft wide.
Who owns Old US 51 over Pass Manchac?
It is owned by the State Highway Agency.