THORNTONS FERRY RD
Carrying THORNTONS FERRY RD over BEAVER BROOK
3.2 MI FR MERRIMACK TL, Hillsborough, New Hampshire
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
THORNTONS FERRY RD in Hillsborough, New Hampshire sits above 1% of rated New Hampshire bridges on inventory load rating (0 t), while its 1970 build year is earlier than 52% of Hillsborough's recorded-year cohort (385 bridges).
THORNTONS FERRY RD in Hillsborough, New Hampshire is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1970, it carries 1 rated component on the inspecting agency's 0-9 scale, and its weakest reported component scores 1. The lowest applicable rating sets the federal condition category, so this Poor result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure NH:000701450010600
INTERSTATE-ERA · STEEL · MULTI-SPAN · CULVERT-LED · LOCAL-ADT · TRACE-LOAD · CAT-POOR
- INTERSTATE-ERA 1950–1979
- STEEL Steel
- MULTI-SPAN 2 spans
- CULVERT-LED Culvert-led
- LOCAL-ADT Local ADT
- TRACE-LOAD Trace load
- CAT-POOR Poor
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Bridge Snapshot: THORNTONS FERRY RD
The THORNTONS FERRY RD bridge in Hillsborough, New Hampshire carries THORNTONS FERRY RD over BEAVER BROOK. It was built in 1970, making it 56 years old today. The structure is built primarily of steel and spans 2 sections, stretching 6.1 meters (20 feet) end to end. Daily traffic averages 388 vehicles, placing it in the lower-traffic tier of New Hampshire bridges. It is owned and maintained by City/Municipal Highway Agency.
The latest FHWA inspection records show culvert at 1/9. The weakest component sits in critical condition. At least one major component here scores 4 or below, which produces a Poor condition classification under FHWA's current reporting rules.
How THORNTONS FERRY RD compares
Age against the county: built in 1970, earlier than 201 of Hillsborough's 385 bridges with a recorded construction year (52%), against a county median build year of 1973. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across New Hampshire bridges with a recorded inventory load rating (2,540 of 2,542 rated).
THORNTONS FERRY RD vs every rated New Hampshire bridge
Inventory load rating (metric tons), FHWA NBI, this state
0 Top 99% higher than 1% of 2,540 bridges
rated New Hampshire bridges, bucketed by value
Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FHWA National Bridge Inventory · August 2026
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Hillsborough inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 385 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 1970
- Material
- Steel
- Number of Spans
- 2
- Structure Length
- 6.1 m (20 ft) 0
- Owner
- City/Municipal Highway Agency
- Avg Daily Traffic
- 388 vehicles/day
- Structure Number
- 000701450010600
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
THORNTONS FERRY RD 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 THORNTONS FERRY RD 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 THORNTONS FERRY RD?
THORNTONS FERRY RD in Hillsborough, New Hampshire on the FHWA's 0–9 scale.
How often is THORNTONS FERRY RD inspected?
THORNTONS FERRY RD'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 388 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. THORNTONS FERRY RD 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 THORNTONS FERRY RD?
THORNTONS FERRY RD has an NBI inventory load rating of 0.0 metric tons.
Who is responsible for maintaining THORNTONS FERRY RD?
THORNTONS FERRY RD is owned and maintained by City/Municipal Highway Agency.
How old is THORNTONS FERRY RD and does age affect safety?
THORNTONS FERRY RD was built in 1970, making it 56 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.
Share this inspection record
Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.