FHWA NBI 2024 Inspection record Public-domain dataset

US 1 NB/LOWR DECK

Carrying US 1 NB/LOWR DECK over OTHER RELIEF

TOLL PL LOWER, Suffolk, Massachusetts

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
22 t Inventory load rating

Bridge Snapshot: US 1 NB/LOWR DECK

The US 1 NB/LOWR DECK bridge in Suffolk, Massachusetts carries US 1 NB/LOWR DECK over OTHER RELIEF. It was built in 1950, making it 76 years old today. The structure is built primarily of steel and spans 12 sections, stretching 326.7 meters (1072 feet) end to end. Daily traffic averages 41,951 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. All reported major components score above the Poor range. Its NBI inventory load rating is 22.2 metric tons.

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

How US 1 NB/LOWR DECK compares

▼ 19.0
Load rating vs Massachusetts average (41.2 t)
Bottom 8%
Lower load rating than 92% of Massachusetts bridges
494
Bridges in Suffolk · 34 in Poor condition
US 1 NB/LOWR DECK 22.2 t
Massachusetts average 41.2 t

Live comparison across Massachusetts.

Historical Sufficiency Rating

PlainBridge-computed
44.4 / 100 - historical 20–49.9 band
Structural adequacy /55
34.4
Serviceability /30
10.0
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 How the historical reference is calculated.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
5/9
Fair (5–6)
Substructure
5/9
Fair (5–6)
Inventory Load Rating
22.2 t
NBI inventory level (metric tons)
Overall Condition
Fair

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

Structural Details

Year Built
1950
Material
Steel
Number of Spans
12
Structure Length
326.7 m (1072 ft)
Deck Width
12.7 m (42 ft)
Owner
State Highway Agency
Avg Daily Traffic
41,951 vehicles/day
Structure Number
B160174X1DOTNBI

Condition Analysis

  • The deck (driving surface) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
  • The superstructure (beams and supports above the deck) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
  • The substructure (piers and abutments) is in fair condition (5/9), with minor deterioration that may require routine maintenance.

How to read this record

This page shows what the last federal inspection recorded, not whether US 1 NB/LOWR DECK 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 US 1 NB/LOWR DECK 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 US 1 NB/LOWR DECK?

US 1 NB/LOWR DECK 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 US 1 NB/LOWR DECK inspected?

US 1 NB/LOWR DECK'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 41,951 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. US 1 NB/LOWR DECK 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 US 1 NB/LOWR DECK?

US 1 NB/LOWR DECK has an NBI inventory load rating of 22.2 metric tons.

Who is responsible for maintaining US 1 NB/LOWR DECK?

US 1 NB/LOWR DECK is owned and maintained by State Highway Agency.

How old is US 1 NB/LOWR DECK and does age affect safety?

US 1 NB/LOWR DECK was built in 1950, making it 76 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.