TIRRELL HILL ROAD
Carrying TIRRELL HILL ROAD over BLACK BROOK
1.9MI Fr Goffstwn Back RD, Hillsborough, New Hampshire
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: TIRRELL HILL ROAD
The TIRRELL HILL ROAD bridge in Hillsborough, New Hampshire carries TIRRELL HILL ROAD over BLACK BROOK. It was built in 1994, making it 32 years old today. The structure is built primarily of steel and spans 1 section, stretching 12.8 meters (42 feet) end to end. Daily traffic averages 1,273 vehicles, placing it in the moderately-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 7/9, superstructure at 4/9, 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 37.2 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How TIRRELL HILL ROAD 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 How the historical reference is calculated.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
- 1994
- Material
- Steel
- Number of Spans
- 1
- Structure Length
- 12.8 m (42 ft)
- Deck Width
- 7.3 m (24 ft)
- Owner
- City/Municipal Highway Agency
- Avg Daily Traffic
- 1,273 vehicles/day
- Structure Number
- 009501620014100
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • At 7/9, the deck (driving surface) is in good shape and shows no significant wear.
- • At 4/9, the superstructure (beams and supports above the deck) is in poor shape, with advanced wear flagged for priority repair.
- • The substructure (piers and abutments) rates fair at 6/9, minor deterioration that routine maintenance should address.
How to read this record
TIRRELL HILL ROAD 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 TIRRELL HILL ROAD against other structures in Hillsborough 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 TIRRELL HILL ROAD?
TIRRELL HILL ROAD in Hillsborough, New Hampshire has a deck rating of 7/9, superstructure rating of 4/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is TIRRELL HILL ROAD inspected?
TIRRELL HILL ROAD'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 1,273 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. TIRRELL HILL ROAD 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 TIRRELL HILL ROAD?
TIRRELL HILL ROAD has an NBI inventory load rating of 37.2 metric tons.
Who is responsible for maintaining TIRRELL HILL ROAD?
TIRRELL HILL ROAD is owned and maintained by City/Municipal Highway Agency.
How old is TIRRELL HILL ROAD and does age affect safety?
TIRRELL HILL ROAD was built in 1994, making it 32 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.