I 93 NB/US1SB
Carrying I 93 NB/US1SB over ST 24 NB
I 93 AT ST 24, Norfolk, Massachusetts
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: I 93 NB/US1SB
The I 93 NB/US1SB bridge in Norfolk, Massachusetts carries I 93 NB/US1SB over ST 24 NB. It was built in 1958, making it 68 years old today. The structure is built primarily of steel continuous and spans 3 sections, stretching 64.6 meters (212 feet) end to end. Daily traffic averages 199,278 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 5/9, superstructure at 4/9, substructure at 6/9. The weakest component sits in poor condition. Because at least one major component scores 4 or lower, this bridge falls in FHWA's Poor condition category. That category is not a closure order. Its NBI inventory load rating is 28.4 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How I 93 NB/US1SB compares
Live comparison across Massachusetts.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 1958
- Material
- Steel Continuous
- Number of Spans
- 3
- Structure Length
- 64.6 m (212 ft)
- Deck Width
- 17.7 m (58 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 199,278 vehicles/day
- Structure Number
- R01005359DOTNBI
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • The superstructure (beams and supports above the deck) rates poor at 4/9, advanced deterioration that should be prioritized for repair.
- • The substructure (piers and abutments) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
How to read this record
I 93 NB/US1SB is in the federal Poor condition category. That is a component-based result, not a closure order.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Understand what Poor condition does and does not mean before drawing conclusions. Poor condition explained
- Compare I 93 NB/US1SB 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/US1SB?
I 93 NB/US1SB in Norfolk, Massachusetts has a deck rating of 5/9, superstructure rating of 4/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is I 93 NB/US1SB inspected?
I 93 NB/US1SB'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 199,278 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/US1SB is currently shown as Poor 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/US1SB?
I 93 NB/US1SB has an NBI inventory load rating of 28.4 metric tons.
Who is responsible for maintaining I 93 NB/US1SB?
I 93 NB/US1SB is owned and maintained by State Highway Agency.
How old is I 93 NB/US1SB and does age affect safety?
I 93 NB/US1SB was built in 1958, making it 68 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.
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.