HWY UNION ST
Carrying HWY UNION ST over WATER MERRIMACK RIVER
AT MERRIMAC RIVER, Essex, Massachusetts
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
HWY UNION ST in Essex, Massachusetts sits above 14% of rated Massachusetts bridges on inventory load rating (26 t), while its 1888 build year is earlier than 93% of Essex's recorded-year cohort (394 bridges).
HWY UNION ST in Essex, Massachusetts is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1888, 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 MA:L04003317DOTNBI
PRE-1950 · MAT-OTHER · LONG-SPAN-RUN · SUPER-LED · HEAVY-ADT · STANDARD-LOAD · CAT-FAIR
- PRE-1950 Pre-1950
- MAT-OTHER Other
- LONG-SPAN-RUN 5 spans
- SUPER-LED Superstructure-led
- HEAVY-ADT Heavy ADT
- STANDARD-LOAD Standard 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: HWY UNION ST
The HWY UNION ST bridge in Essex, Massachusetts carries HWY UNION ST over WATER MERRIMACK RIVER. It was built in 1888, making it 138 years old today. It was last reconstructed in 2012, extending its service life. The structure is built primarily of aluminum/iron and spans 5 sections, stretching 185.9 meters (610 feet) end to end. Daily traffic averages 24,050 vehicles, placing it in the heavily-trafficked tier of Massachusetts bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 8/9, superstructure at 5/9, substructure at 7/9. The weakest component sits in fair condition. All reported major components score above the Poor range.
How HWY UNION ST compares
Age against the county: built in 1888, earlier than 368 of Essex's 394 bridges with a recorded construction year (93%), against a county median build year of 1962. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Massachusetts bridges with a recorded inventory load rating (5,295 rated).
HWY UNION ST vs every rated Massachusetts bridge
Inventory load rating (metric tons), FHWA NBI, this state
26 Top 86% higher than 14% of 5,295 bridges
rated Massachusetts 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.
Essex inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 395 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
- 1888
- Last Reconstructed
- 2012
- Material
- Aluminum/Iron
- Number of Spans
- 5
- Structure Length
- 185.9 m (610 ft)
- Deck Width
- 14.9 m (49 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 24,050 vehicles/day
- Structure Number
- L04003317DOTNBI
Condition Analysis
- • The deck (driving surface) rates good at 8/9, with no significant deterioration on file.
- • At 5/9, the superstructure (beams and supports above the deck) shows fair condition, with minor wear flagged for upkeep.
- • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.
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 HWY UNION ST 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 HWY UNION ST against other structures in Essex and across Massachusetts. Massachusetts 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 HWY UNION ST?
HWY UNION ST in Essex, Massachusetts has a deck rating of 8/9, superstructure rating of 5/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is HWY UNION ST inspected?
HWY UNION 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 24,050 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. HWY UNION ST 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 HWY UNION ST?
HWY UNION ST has an NBI inventory load rating of 25.9 metric tons.
Who is responsible for maintaining HWY UNION ST?
HWY UNION ST is owned and maintained by State Highway Agency.
How old is HWY UNION ST and does age affect safety?
HWY UNION ST was built in 1888, making it 138 years old and last reconstructed in 2012.
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.