I 93 /US1/ST3
Carrying I 93 /US1/ST3 over RR CSX SPUR
2 MI S OF JCT I90&I93, Suffolk, Massachusetts
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
I 93 /US1/ST3 in Suffolk, Massachusetts is rated Fair in the FHWA's 2024 National Bridge Inventory.
Built in 1958, 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 MA:B162603DNDOTNBI
INTERSTATE-ERA · STEEL · SINGLE-SPAN · TIED-CTRL · HEAVY-ADT · HEAVY-LOAD · CAT-FAIR
- INTERSTATE-ERA 1950–1979
- STEEL Steel
- SINGLE-SPAN Single span
- 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: I 93 /US1/ST3
The I 93 /US1/ST3 bridge in Suffolk, Massachusetts carries I 93 /US1/ST3 over RR CSX SPUR. It was built in 1958, making it 68 years old today. It was last reconstructed in 1984, extending its service life. The structure is built primarily of steel and spans 1 section, stretching 24.8 meters (81 feet) end to end. Daily traffic averages 188,320 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 7/9, superstructure at 6/9, substructure at 6/9. The weakest component sits in fair condition. All reported major components score above the Poor range.
How I 93 /US1/ST3 compares
Age against the county: built in 1958, earlier than 305 of Suffolk's 488 bridges with a recorded construction year (63%), against a county median build year of 1970. 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).
I 93 /US1/ST3 vs every rated Massachusetts bridge
Inventory load rating (metric tons), FHWA NBI, this state
42 Top 35% higher than 65% 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.
Suffolk inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 489 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
- 1958
- Last Reconstructed
- 1984
- Material
- Steel
- Number of Spans
- 1
- Structure Length
- 24.8 m (81 ft)
- Deck Width
- 33.9 m (111 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 188,320 vehicles/day
- Structure Number
- B162603DNDOTNBI
Condition Analysis
- • The deck (driving surface) rates good at 7/9, with no significant deterioration on file.
- • The superstructure (beams and supports above the deck) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
- • The substructure (piers and abutments) is in fair condition (6/9), 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 I 93 /US1/ST3 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 I 93 /US1/ST3 against other structures in Suffolk 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 I 93 /US1/ST3?
I 93 /US1/ST3 in Suffolk, Massachusetts has a deck rating of 7/9, superstructure rating of 6/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is I 93 /US1/ST3 inspected?
I 93 /US1/ST3'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 188,320 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. I 93 /US1/ST3 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 I 93 /US1/ST3?
I 93 /US1/ST3 has an NBI inventory load rating of 42.0 metric tons.
Who is responsible for maintaining I 93 /US1/ST3?
I 93 /US1/ST3 is owned and maintained by State Highway Agency.
How old is I 93 /US1/ST3 and does age affect safety?
I 93 /US1/ST3 was built in 1958, making it 68 years old and last reconstructed in 1984.
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.