ROUTE 146
Carrying ROUTE 146 over WEST RIVER
0.4 MI W OF ROUTE 77, Unknown County, Connecticut
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
ROUTE 146 in Unknown County, Connecticut sits above 34% of rated Connecticut bridges on inventory load rating (34 t), while its 1910 build year is earlier than 96% of Unknown County's recorded-year cohort (893 bridges).
ROUTE 146 in Unknown County, Connecticut is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1910, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 4. The lowest applicable rating sets the federal condition category, so this Poor 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:04379
PRE-1950 · PRESTRESS · SINGLE-SPAN · TIED-CTRL · ARTERIAL-ADT · STANDARD-LOAD · CAT-POOR
- PRE-1950 Pre-1950
- PRESTRESS Prestressed concrete
- SINGLE-SPAN Single span
- TIED-CTRL Tied control
- ARTERIAL-ADT Arterial ADT
- STANDARD-LOAD Standard load
- CAT-POOR Poor
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: ROUTE 146
The ROUTE 146 bridge in Unknown County, Connecticut carries ROUTE 146 over WEST RIVER. It was built in 1910, making it 116 years old today. It was last reconstructed in 1982, extending its service life. The structure is built primarily of prestressed concrete and spans 1 section, stretching 17.4 meters (57 feet) end to end. Daily traffic averages 5,500 vehicles, placing it in the moderately-trafficked tier of Connecticut bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection places the weakest component in poor condition (see the full component ratings below). At least one major component here scores 4 or below, which produces a Poor condition classification under FHWA's current reporting rules.
How ROUTE 146 compares
Age against the county: built in 1910, earlier than 857 of Unknown County's 893 bridges with a recorded construction year (96%), against a county median build year of 1965. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Connecticut bridges with a recorded inventory load rating (4,365 rated).
ROUTE 146 vs every rated Connecticut bridge
Inventory load rating (metric tons), FHWA NBI, this state
34 Top 66% higher than 34% 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 893 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
- 1910
- Last Reconstructed
- 1982
- Material
- Prestressed Concrete
- Number of Spans
- 1
- Structure Length
- 17.4 m (57 ft)
- Deck Width
- 12.8 m (42 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 5,500 vehicles/day
- Structure Number
- 04379
Condition Analysis
- • At 4/9, the deck (driving surface) is in poor shape, with advanced wear on file for this vintage.
- • At 4/9, the superstructure (beams and supports above the deck) is in poor shape, with advanced wear on file for this vintage.
- • The substructure (piers and abutments) rates good at 7/9, with no significant deterioration on file.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
ROUTE 146 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 ROUTE 146 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 ROUTE 146?
ROUTE 146 in Unknown County, Connecticut has a deck rating of 4/9, superstructure rating of 4/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is ROUTE 146 inspected?
ROUTE 146'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 5,500 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. ROUTE 146 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 ROUTE 146?
ROUTE 146 has an NBI inventory load rating of 33.7 metric tons.
Who is responsible for maintaining ROUTE 146?
ROUTE 146 is owned and maintained by State Highway Agency.
How old is ROUTE 146 and does age affect safety?
ROUTE 146 was built in 1910, making it 116 years old and last reconstructed in 1982.
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.