SALMON STREET WB
Carrying SALMON STREET WB over MERRIMACK RIVER CSX RD
.3MI W JCT US 3, Hillsborough, New Hampshire
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
SALMON STREET WB in Hillsborough, New Hampshire sits above 69% of rated New Hampshire bridges on inventory load rating (45 t), while its 1970 build year is earlier than 52% of Hillsborough's recorded-year cohort (385 bridges).
SALMON STREET WB in Hillsborough, New Hampshire is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1970, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 5. The lowest applicable rating sets the federal condition category, so this Fair 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:016101060007200
INTERSTATE-ERA · STEEL · LONG-SPAN-RUN · TIED-CTRL · HEAVY-ADT · HEAVY-LOAD · CAT-FAIR
- INTERSTATE-ERA 1950–1979
- STEEL Steel
- LONG-SPAN-RUN 4 spans
- TIED-CTRL Tied control
- HEAVY-ADT Heavy ADT
- HEAVY-LOAD Heavy load
- CAT-FAIR Fair
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: SALMON STREET WB
The SALMON STREET WB bridge in Hillsborough, New Hampshire carries SALMON STREET WB over MERRIMACK RIVER CSX RD. It was built in 1970, making it 56 years old today. It was last reconstructed in 1999, extending its service life. The structure is built primarily of steel continuous and spans 4 sections, stretching 261.5 meters (858 feet) end to end. Daily traffic averages 12,785 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 5/9, superstructure at 5/9, substructure at 5/9. The weakest component sits in fair condition. No reported major component scores in the Poor range under the current federal condition thresholds.
How SALMON STREET WB 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).
SALMON STREET WB vs every rated New Hampshire bridge
Inventory load rating (metric tons), FHWA NBI, this state
45 Top 31% higher than 69% 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.
Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.
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
- Last Reconstructed
- 1999
- Material
- Steel Continuous
- Number of Spans
- 4
- Structure Length
- 261.5 m (858 ft)
- Deck Width
- 11.3 m (37 ft)
- Owner
- City/Municipal Highway Agency
- Avg Daily Traffic
- 12,785 vehicles/day
- Structure Number
- 016101060007200
Condition Analysis
- • At 5/9, the deck (driving surface) shows fair condition, with minor wear flagged for upkeep.
- • The superstructure (beams and supports above the deck) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • The substructure (piers and abutments) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether SALMON STREET WB is safe to cross today. Here is how to use it.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Learn how the 0–9 condition scale and Good/Fair/Poor categories are defined. How condition ratings work
- Compare SALMON STREET WB 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 SALMON STREET WB?
SALMON STREET WB in Hillsborough, New Hampshire has a deck rating of 5/9, superstructure rating of 5/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.
How often is SALMON STREET WB inspected?
SALMON STREET WB'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 12,785 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. SALMON STREET WB is currently shown as Fair condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for SALMON STREET WB?
SALMON STREET WB has an NBI inventory load rating of 44.5 metric tons.
Who is responsible for maintaining SALMON STREET WB?
SALMON STREET WB is owned and maintained by City/Municipal Highway Agency.
How old is SALMON STREET WB and does age affect safety?
SALMON STREET WB was built in 1970, making it 56 years old and last reconstructed in 1999.
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.