US 4 Mechanic ST over Mascoma River
PoorGrafton County, New Hampshire · 5.4 MI from Hanover Tl · Structure no. 014401000011000
- Built
- 1977
- 48 years old
- Condition
- Poor
- inspected October 2024
- Type
- Stringer/Multi-beam or Girder
- Steel
- Length
- 89 ft
- 1 main span
- Daily traffic
- 12,803
- 2023 count
- Owner
- City
- City or Municipal Highway Agency
About this bridge
US 4 Mechanic ST over Mascoma River is a steel stringer/multi-beam or girder carrying US 4 Mechanic ST over Mascoma River in Grafton County, New Hampshire. It was built in 1977, so it is 48 years old, younger than the New Hampshire average of 56.9 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.
It carries about 12,803 vehicles a day, roughly 5% of them trucks, projected to reach 18,948 by 2043. The structure is 89 ft (27.1 m) long and 73 ft wide. If it were closed, the detour would be 5 mi (8 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 | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 4 Mechanic ST over Mascoma River built?
It was built in 1977, making it 48 years old in 2025.
What condition is US 4 Mechanic ST over Mascoma River 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 October 2024.
How much traffic does US 4 Mechanic ST over Mascoma River carry?
About 12,803 vehicles per day (2023 count), of which roughly 5% are trucks.
How long is US 4 Mechanic ST over Mascoma River?
The structure is 89 ft (27.1 m) long with a longest span of 82 ft (25 m) and a deck 73 ft wide.
Who owns US 4 Mechanic ST over Mascoma River?
It is owned by the City or Municipal Highway Agency.