US 4,MECHANIC ST
Carrying US 4,MECHANIC ST over MASCOMA RIVER
5.4 MI FROM HANOVER TL, Grafton, New Hampshire
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: US 4,MECHANIC ST
The US 4,MECHANIC ST bridge in Grafton, New Hampshire carries US 4,MECHANIC ST over MASCOMA RIVER. It was built in 1977, making it 49 years old today. The structure is built primarily of steel and spans 1 section, stretching 27.1 meters (89 feet) end to end. Daily traffic averages 12,552 vehicles, placing it in the heavily-trafficked tier of New Hampshire bridges. It is owned and maintained by City/Municipal Highway Agency.
The latest FHWA inspection records show a deck rating of 4/9, superstructure at 7/9, substructure at 6/9. The weakest component sits in poor condition. At least one major component here scores 4 or below, which produces a Poor condition classification under FHWA's current reporting rules. Its NBI inventory load rating is 32.8 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How US 4,MECHANIC ST compares
Live comparison across New Hampshire.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 1977
- Material
- Steel
- Number of Spans
- 1
- Structure Length
- 27.1 m (89 ft)
- Deck Width
- 22.1 m (73 ft)
- Owner
- City/Municipal Highway Agency
- Avg Daily Traffic
- 12,552 vehicles/day
- Structure Number
- 014401000011000
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) rates poor at 4/9, advanced deterioration that should be prioritized for repair.
- • The superstructure (beams and supports above the deck) is in good condition (7/9), showing no significant deterioration.
- • The substructure (piers and abutments) rates fair at 6/9, minor deterioration that routine maintenance should address.
How to read this record
US 4,MECHANIC ST is in the federal Poor condition category. That is a component-based result, not a closure order.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Understand what Poor condition does and does not mean before drawing conclusions. Poor condition explained
- Compare US 4,MECHANIC ST against other structures in Grafton and across New Hampshire. New Hampshire bridges
- Noticed visible damage or a safety concern? Report it to the agency that owns the bridge, or call 911 in an emergency. How to report a bridge
Condition codes come straight from the FHWA National Bridge Inventory and are not a real-time safety judgment. Only the owning agency, a state DOT, county, or other owner, can post, restrict, or close a bridge.
Frequently Asked Questions
What do the condition ratings mean for US 4,MECHANIC ST?
US 4,MECHANIC ST in Grafton, New Hampshire has a deck rating of 4/9, superstructure rating of 7/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is US 4,MECHANIC ST inspected?
US 4,MECHANIC ST's responsible agency sets its routine interval under FHWA's risk-based inspection rules; this page does not expose the scheduled interval. It carries about 12,552 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. US 4,MECHANIC ST is currently shown as Poor condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for US 4,MECHANIC ST?
US 4,MECHANIC ST has an NBI inventory load rating of 32.8 metric tons.
Who is responsible for maintaining US 4,MECHANIC ST?
US 4,MECHANIC ST is owned and maintained by City/Municipal Highway Agency.
How old is US 4,MECHANIC ST and does age affect safety?
US 4,MECHANIC ST was built in 1977, making it 49 years old.
Disclaimer: Bridge condition data is from the FHWA NBI and reflects the last reported inspection. A Poor condition rating is not a live declaration that a bridge is closed or unsafe for travel. For current closure, posting, or safety information, contact the responsible transportation agency.
Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.