INTERSTATE-384 EB
Carrying INTERSTATE-384 EB over BIRCH MOUNTAIN BROOK
AT EXIT 4, Unknown County, Connecticut
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
INTERSTATE-384 EB in Unknown County, Connecticut sits above 3% of rated Connecticut bridges on inventory load rating (21 t), while its 1970 build year is earlier than 45% of Unknown County's recorded-year cohort (914 bridges).
INTERSTATE-384 EB in Unknown County, Connecticut is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1970, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 6. The lowest applicable rating sets the federal condition category, so this Fair result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure CT:03592
INTERSTATE-ERA · STEEL · MULTI-SPAN · TIED-CTRL · HEAVY-ADT · STANDARD-LOAD · CAT-FAIR
- INTERSTATE-ERA 1950–1979
- STEEL Steel
- MULTI-SPAN 3 spans
- TIED-CTRL Tied control
- HEAVY-ADT Heavy ADT
- STANDARD-LOAD Standard load
- CAT-FAIR Fair
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Structural health score
A composite of the deck, superstructure, and substructure NBI condition ratings plus the inventory load rating, benchmarked against the full national bridge corpus, distinct from the Good/Fair/Poor category above.
Bridge Snapshot: INTERSTATE-384 EB
The INTERSTATE-384 EB bridge in Unknown County, Connecticut carries INTERSTATE-384 EB over BIRCH MOUNTAIN BROOK. It was built in 1970, making it 56 years old today. The structure is built primarily of steel continuous and spans 3 sections, stretching 81.4 meters (267 feet) end to end. Daily traffic averages 19,350 vehicles, placing it in the heavily-trafficked tier of Connecticut bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection places the weakest component in fair condition (see the full component ratings below). All reported major components score above the Poor range.
How INTERSTATE-384 EB compares
Age against the county: built in 1970, earlier than 411 of Unknown County's 914 bridges with a recorded construction year (45%), against a county median build year of 1969. This is one of the newer structures in its county.
Live comparison across Connecticut bridges with a recorded inventory load rating (4,365 rated).
INTERSTATE-384 EB vs every rated Connecticut bridge
Inventory load rating (metric tons), FHWA NBI, this state
21 Top 97% higher than 3% of 4,365 bridges
rated Connecticut bridges, bucketed by value
Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FHWA National Bridge Inventory · August 2026
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.
Unknown County inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 914 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 1970
- Material
- Steel Continuous
- Number of Spans
- 3
- Structure Length
- 81.4 m (267 ft)
- Deck Width
- 19.4 m (64 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 19,350 vehicles/day
- Structure Number
- 03592
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) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
- • The substructure (piers and abutments) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether INTERSTATE-384 EB 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 INTERSTATE-384 EB against other structures in Unknown County and across Connecticut. Connecticut 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 INTERSTATE-384 EB?
INTERSTATE-384 EB in Unknown County, Connecticut has a deck rating of 6/9, superstructure rating of 6/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is INTERSTATE-384 EB inspected?
INTERSTATE-384 EB'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 19,350 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. INTERSTATE-384 EB 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 INTERSTATE-384 EB?
INTERSTATE-384 EB has an NBI inventory load rating of 21.1 metric tons.
Who is responsible for maintaining INTERSTATE-384 EB?
INTERSTATE-384 EB is owned and maintained by State Highway Agency.
How old is INTERSTATE-384 EB and does age affect safety?
INTERSTATE-384 EB was built in 1970, making it 56 years old.
Share this inspection record
Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.