FHWA NBI 2024 Inspection record Public-domain dataset

CHEMICAL ROAD

Carrying CHEMICAL ROAD over WARNER RIVER

0.2 MI FROM JOPPA ROAD, Merrimack, New Hampshire

Inventory: FHWA NBI 2024 · last ETL August 2026

FHWA NBI record, refreshed with each annual release.

Fair
13 t Inventory load rating Lower than 97% of rated New Hampshire bridges

CHEMICAL ROAD in Merrimack, New Hampshire sits above 3% of rated New Hampshire bridges on inventory load rating (13 t), while its 1966 build year is earlier than 45% of Merrimack's recorded-year cohort (326 bridges).

CHEMICAL ROAD in Merrimack, New Hampshire is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1966, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 6. 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:026301810011200

INTERSTATE-ERA · STEEL · MULTI-SPAN · TIED-CTRL · LOCAL-ADT · LIGHT-LOAD · CAT-FAIR

  • INTERSTATE-ERA 1950–1979
  • STEEL Steel
  • MULTI-SPAN 2 spans
  • TIED-CTRL Tied control
  • LOCAL-ADT Local ADT
  • LIGHT-LOAD Light 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: CHEMICAL ROAD

The CHEMICAL ROAD bridge in Merrimack, New Hampshire carries CHEMICAL ROAD over WARNER RIVER. It was built in 1966, making it 60 years old today. The structure is built primarily of steel and spans 2 sections, stretching 36.3 meters (119 feet) end to end. Daily traffic averages 84 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 a deck rating of 6/9, superstructure at 6/9, substructure at 7/9. The weakest component sits in fair condition. None of this bridge's reported major components fall into the Poor condition range.

How CHEMICAL ROAD compares

▼ 25.7
Load rating vs New Hampshire average (38.4 t; 2,540 of 2,542 rated)
326
Bridges in Merrimack · 26 in Poor condition

Age against the county: built in 1966, earlier than 148 of Merrimack's 326 bridges with a recorded construction year (45%), against a county median build year of 1966.

CHEMICAL ROAD 12.7 t
New Hampshire average (2,540 of 2,542 rated) 38.4 t

Live comparison across New Hampshire bridges with a recorded inventory load rating (2,540 of 2,542 rated).

CHEMICAL ROAD vs every rated New Hampshire bridge

Inventory load rating (metric tons), FHWA NBI, this state

13 Top 97% higher than 3% 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

Deck
6/9
Fair (5–6)
Superstructure
6/9
Fair (5–6)
Substructure
7/9
Good (7–9)
Inventory Load Rating
12.7 t
NBI inventory level (metric tons)
Overall Condition
Fair

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.

Merrimack inventory by recorded NBI category

Exclusive Good/Fair/Poor bands across all 326 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
1966
Material
Steel
Number of Spans
2
Structure Length
36.3 m (119 ft)
Deck Width
9.7 m (32 ft)
Owner
City/Municipal Highway Agency
Avg Daily Traffic
84 vehicles/day
Structure Number
026301810011200

Condition Analysis

  • At 6/9, the deck (driving surface) shows fair condition, with minor wear flagged for upkeep.
  • The superstructure (beams and supports above the deck) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
  • At 7/9, the substructure (piers and abutments) is in good shape and shows no significant wear.

How to read this record

This page shows what the last federal inspection recorded, not whether CHEMICAL ROAD 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 CHEMICAL ROAD against other structures in Merrimack 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 CHEMICAL ROAD?

CHEMICAL ROAD in Merrimack, New Hampshire has a deck rating of 6/9, superstructure rating of 6/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.

How often is CHEMICAL ROAD inspected?

CHEMICAL 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 84 vehicles per day.

What does “structurally deficient” mean in older bridge reports?

FHWA retired that reported status beginning with the 2018 archive. CHEMICAL ROAD 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 CHEMICAL ROAD?

CHEMICAL ROAD has an NBI inventory load rating of 12.7 metric tons.

Who is responsible for maintaining CHEMICAL ROAD?

CHEMICAL ROAD is owned and maintained by City/Municipal Highway Agency.

How old is CHEMICAL ROAD and does age affect safety?

CHEMICAL ROAD was built in 1966, making it 60 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.

Data sourced from the Federal Highway Administration National Bridge Inventory. See our methodology for details. Retrieved and formatted by PlainBridges

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Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.

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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.