FHWA NBI 2024 Inspection record Public-domain dataset

I 93 BT NB4-N ABT

Carrying I 93 BT NB4-N ABT over I 93 CONN D & K

1.9 KM N OF JCT US1&I93, Suffolk, Massachusetts

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
34 t Inventory load rating

Bridge Snapshot: I 93 BT NB4-N ABT

The I 93 BT NB4-N ABT bridge in Suffolk, Massachusetts carries I 93 BT NB4-N ABT over I 93 CONN D & K. It was built in 1970, making it 56 years old today. The structure is built primarily of steel and spans 4 sections, stretching 112.8 meters (370 feet) end to end. Daily traffic averages 65,702 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 6/9, superstructure at 5/9, substructure at 5/9. The weakest component sits in fair condition. None of this bridge's reported major components fall into the Poor condition range. Its NBI inventory load rating is 33.7 metric tons.

Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.

How I 93 BT NB4-N ABT compares

▼ 7.5
Load rating vs Massachusetts average (41.2 t)
Bottom 37%
Lower load rating than 63% of Massachusetts bridges
494
Bridges in Suffolk · 34 in Poor condition
I 93 BT NB4-N ABT 33.7 t
Massachusetts average 41.2 t

Live comparison across Massachusetts.

Historical Sufficiency Rating

PlainBridge-computed
75.5 / 100 - historical 50–79.9 band
Structural adequacy /55
45.0
Serviceability /30
25.0
Essentiality /15
5.5
Special reductions
0

FHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.

Condition Ratings

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

Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.

Structural Details

Year Built
1970
Material
Steel
Number of Spans
4
Structure Length
112.8 m (370 ft)
Deck Width
21.9 m (72 ft)
Owner
State Highway Agency
Avg Daily Traffic
65,702 vehicles/day
Structure Number
B162813BRDOTNBI

Condition Analysis

  • The deck (driving surface) rates fair at 6/9, minor deterioration that routine maintenance should address.
  • The superstructure (beams and supports above the deck) rates fair at 5/9, minor deterioration that routine maintenance should address.
  • At 5/9, the substructure (piers and abutments) shows fair condition, with minor wear flagged for upkeep.

How to read this record

This page shows what the last federal inspection recorded, not whether I 93 BT NB4-N ABT 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 BT NB4-N ABT 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 BT NB4-N ABT?

I 93 BT NB4-N ABT in Suffolk, Massachusetts has a deck rating of 6/9, superstructure rating of 5/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.

How often is I 93 BT NB4-N ABT inspected?

I 93 BT NB4-N ABT'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 65,702 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. I 93 BT NB4-N ABT 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 BT NB4-N ABT?

I 93 BT NB4-N ABT has an NBI inventory load rating of 33.7 metric tons.

Who is responsible for maintaining I 93 BT NB4-N ABT?

I 93 BT NB4-N ABT is owned and maintained by State Highway Agency.

How old is I 93 BT NB4-N ABT and does age affect safety?

I 93 BT NB4-N ABT 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.

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

Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.