Nj 31 SB over I-78
FairHunterdon County, New Jersey · At Nj 31 Interchange · Structure no. 1017153
- Built
- 1967
- 58 years old, rebuilt 1994
- Condition
- Fair
- inspected July 2024
- Type
- Stringer/Multi-beam or Girder
- Steel
- Length
- 222 ft
- 2 main spans
- Daily traffic
- 14,852
- 2022 count
- Owner
- State
- State Highway Agency
About this bridge
Nj 31 SB over I-78 is a steel stringer/multi-beam or girder carrying Nj 31 SB over I-78 in Hunterdon County, New Jersey. It was built in 1967 and reconstructed in 1994, so it is 58 years old, younger than the New Jersey average of 58.5 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 14,852 vehicles a day, roughly 4% of them trucks, projected to reach 17,822 by 2042. The structure is 222 ft (67.7 m) long and 47 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 |
|---|---|---|
| Deck | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Nj 31 SB over I-78 built?
It was built in 1967, making it 58 years old in 2025. It was reconstructed in 1994.
What condition is Nj 31 SB over I-78 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 July 2024.
How much traffic does Nj 31 SB over I-78 carry?
About 14,852 vehicles per day (2022 count), of which roughly 4% are trucks.
How long is Nj 31 SB over I-78?
The structure is 222 ft (67.7 m) long with a longest span of 115 ft (35.1 m) and a deck 47 ft wide.
Who owns Nj 31 SB over I-78?
It is owned by the State Highway Agency.