MARION AVENUE
Carrying MARION AVENUE over EIGHT MILE RIVER
475 FT E OF I-84, Unknown County, Connecticut
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
MARION AVENUE in Unknown County, Connecticut sits above 63% of rated Connecticut bridges on inventory load rating (45 t), while its 1979 build year is earlier than 38% of Unknown County's recorded-year cohort (914 bridges).
MARION AVENUE in Unknown County, Connecticut is rated Good in the FHWA's 2024 National Bridge Inventory. Built in 1979, it carries 1 rated component on the inspecting agency's 0-9 scale, and its weakest reported component scores 7. The lowest applicable rating sets the federal condition category, so this Good 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:04336
INTERSTATE-ERA · CONCRETE · MULTI-SPAN · CULVERT-LED · HEAVY-ADT · HEAVY-LOAD · CAT-GOOD
- INTERSTATE-ERA 1950–1979
- CONCRETE Concrete
- MULTI-SPAN 2 spans
- CULVERT-LED Culvert-led
- HEAVY-ADT Heavy ADT
- HEAVY-LOAD Heavy load
- CAT-GOOD Good
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: MARION AVENUE
The MARION AVENUE bridge in Unknown County, Connecticut carries MARION AVENUE over EIGHT MILE RIVER. It was built in 1979, making it 47 years old today. It was last reconstructed in 2004, extending its service life. The structure is built primarily of concrete continuous and spans 2 sections, stretching 11.6 meters (38 feet) end to end. Daily traffic averages 12,400 vehicles, placing it in the heavily-trafficked tier of Connecticut bridges. It is owned and maintained by Town/Township Highway Agency.
The latest FHWA inspection places the weakest component in good condition (see the full component ratings below). All reported major components score above the Poor range.
How MARION AVENUE compares
Age against the county: built in 1979, earlier than 344 of Unknown County's 914 bridges with a recorded construction year (38%), 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).
MARION AVENUE vs every rated Connecticut bridge
Inventory load rating (metric tons), FHWA NBI, this state
45 Top 37% higher than 63% 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.
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
- 1979
- Last Reconstructed
- 2004
- Material
- Concrete Continuous
- Number of Spans
- 2
- Structure Length
- 11.6 m (38 ft)
- Deck Width
- 26.4 m (87 ft)
- Owner
- Town/Township Highway Agency
- Avg Daily Traffic
- 12,400 vehicles/day
- Structure Number
- 04336
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 MARION AVENUE 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 MARION AVENUE 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 MARION AVENUE?
MARION AVENUE in Unknown County, Connecticut on the FHWA's 0–9 scale.
How often is MARION AVENUE inspected?
MARION AVENUE'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 12,400 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. MARION AVENUE 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 MARION AVENUE?
MARION AVENUE has an NBI inventory load rating of 45.4 metric tons.
Who is responsible for maintaining MARION AVENUE?
MARION AVENUE is owned and maintained by Town/Township Highway Agency.
How old is MARION AVENUE and does age affect safety?
MARION AVENUE was built in 1979, making it 47 years old and last reconstructed in 2004.
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.