FHWA NBI 2024 Inspection record Public-domain dataset

I 495 SB

Carrying I 495 SB over WATER CONCORD RIVER

3.2KM SOUTH OF RT 38, Middlesex, Massachusetts

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Good
45 t Inventory load rating

Bridge Snapshot: I 495 SB

The I 495 SB bridge in Middlesex, Massachusetts carries I 495 SB over WATER CONCORD RIVER. It was built in 2011, making it 15 years old today. The structure is built primarily of steel and spans 1 section, stretching 56.9 meters (187 feet) end to end. Daily traffic averages 64,400 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 7/9, substructure at 8/9. The weakest component sits in good condition. All reported major components score above the Poor range. Its NBI inventory load rating is 44.7 metric tons.

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

How I 495 SB compares

▲ 3.5
Load rating vs Massachusetts average (41.2 t)
Top 30%
Higher load rating than 70% of Massachusetts bridges
820
Bridges in Middlesex · 72 in Poor condition
I 495 SB 44.7 t
Massachusetts average 41.2 t

Live comparison across Massachusetts.

Historical Sufficiency Rating

PlainBridge-computed
92.0 / 100 - historical 80–100 band
Structural adequacy /55
55.0
Serviceability /30
30.0
Essentiality /15
7.0
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 How the historical reference is calculated.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
7/9
Good (7–9)
Superstructure
7/9
Good (7–9)
Substructure
8/9
Good (7–9)
Inventory Load Rating
44.7 t
NBI inventory level (metric tons)
Overall Condition
Good

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

Structural Details

Year Built
2011
Material
Steel
Number of Spans
1
Structure Length
56.9 m (187 ft)
Deck Width
17.8 m (58 ft)
Owner
State Highway Agency
Avg Daily Traffic
64,400 vehicles/day
Structure Number
L15082AQBDOTNBI

Condition Analysis

  • At 7/9, the deck (driving surface) is in good shape and shows no significant wear.
  • The superstructure (beams and supports above the deck) rates good at 7/9, with no significant deterioration on file.
  • The substructure (piers and abutments) rates good at 8/9, with no significant deterioration on file.

How to read this record

This page shows what the last federal inspection recorded, not whether I 495 SB 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 495 SB against other structures in Middlesex 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 495 SB?

I 495 SB in Middlesex, Massachusetts has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 8/9 on the FHWA's 0–9 scale.

How often is I 495 SB inspected?

I 495 SB'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 64,400 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. I 495 SB is currently shown as Good condition from its component ratings; that category is not a live closure or safety decision.

What is the inventory load rating for I 495 SB?

I 495 SB has an NBI inventory load rating of 44.7 metric tons.

Who is responsible for maintaining I 495 SB?

I 495 SB is owned and maintained by State Highway Agency.

How old is I 495 SB and does age affect safety?

I 495 SB was built in 2011, making it 15 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.