FHWA NBI 2024 Inspection record Public-domain dataset

I 93 NB/US1NB

Carrying I 93 NB/US1NB over ST 37 GRANITE ST

I 93 AT ST 37, Norfolk, Massachusetts

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
34 t Inventory load rating

Bridge Snapshot: I 93 NB/US1NB

The I 93 NB/US1NB bridge in Norfolk, Massachusetts carries I 93 NB/US1NB over ST 37 GRANITE ST. It was built in 1957, making it 69 years old today. The structure is built primarily of prestressed concrete and spans 2 sections, stretching 32.3 meters (106 feet) end to end. Daily traffic averages 95,449 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 7/9, 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. Its NBI inventory load rating is 34.1 metric tons.

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

How I 93 NB/US1NB compares

▼ 7.1
Load rating vs Massachusetts average (41.2 t)
Bottom 39%
Lower load rating than 61% of Massachusetts bridges
348
Bridges in Norfolk · 14 in Poor condition
I 93 NB/US1NB 34.1 t
Massachusetts average 41.2 t

Live comparison across Massachusetts.

Historical Sufficiency Rating

PlainBridge-computed
83.0 / 100 - historical 80–100 band
Structural adequacy /55
55.0
Serviceability /30
28.0
Essentiality /15
0.0
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 How the historical reference is calculated.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
7/9
Good (7–9)
Substructure
7/9
Good (7–9)
Inventory Load Rating
34.1 t
NBI inventory level (metric tons)
Overall Condition
Fair

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

Structural Details

Year Built
1957
Material
Prestressed Concrete
Number of Spans
2
Structure Length
32.3 m (106 ft)
Deck Width
22.0 m (72 ft)
Owner
State Highway Agency
Avg Daily Traffic
95,449 vehicles/day
Structure Number
B21048356DOTNBI

Condition Analysis

  • The deck (driving surface) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
  • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
  • 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 I 93 NB/US1NB 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 NB/US1NB against other structures in Norfolk 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 NB/US1NB?

I 93 NB/US1NB in Norfolk, Massachusetts has a deck rating of 6/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.

How often is I 93 NB/US1NB inspected?

I 93 NB/US1NB'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 95,449 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. I 93 NB/US1NB 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 NB/US1NB?

I 93 NB/US1NB has an NBI inventory load rating of 34.1 metric tons.

Who is responsible for maintaining I 93 NB/US1NB?

I 93 NB/US1NB is owned and maintained by State Highway Agency.

How old is I 93 NB/US1NB and does age affect safety?

I 93 NB/US1NB was built in 1957, making it 69 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.