ISON LN
Carrying ISON LN over NS (CNO&TP) SYSTEM
.1 MI W OF JCT KY 342, Mercer, Kentucky
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
ISON LN in Mercer, Kentucky sits above 2% of rated Kentucky bridges on inventory load rating (7 t), while its 1940 build year is earlier than 89% of Mercer's recorded-year cohort (75 bridges).
ISON LN in Mercer, Kentucky is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1940, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 5. 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 KY:084R00604N
PRE-1950 · STEEL · LONG-SPAN-RUN · TIED-CTRL · LOCAL-ADT · LIGHT-LOAD · CAT-FAIR
- PRE-1950 Pre-1950
- STEEL Steel
- LONG-SPAN-RUN 5 spans
- TIED-CTRL Tied control
- LOCAL-ADT Local ADT
- LIGHT-LOAD Light 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.
Bridge Snapshot: ISON LN
The ISON LN bridge in Mercer, Kentucky carries ISON LN over NS (CNO&TP) SYSTEM. It was built in 1940, making it 86 years old today. The structure is built primarily of steel and spans 5 sections, stretching 28.7 meters (94 feet) end to end. Daily traffic averages 84 vehicles, placing it in the lower-traffic tier of Kentucky bridges. It is owned and maintained by Railroad.
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. No reported major component scores in the Poor range under the current federal condition thresholds.
How ISON LN compares
Age against the county: built in 1940, earlier than 67 of Mercer's 75 bridges with a recorded construction year (89%), against a county median build year of 1990. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Kentucky bridges with a recorded inventory load rating (14,532 of 14,548 rated).
ISON LN vs every rated Kentucky bridge
Inventory load rating (metric tons), FHWA NBI, this state
7 Top 98% higher than 2% of 14,532 bridges
rated Kentucky 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.
Mercer inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 75 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
- 1940
- Material
- Steel
- Number of Spans
- 5
- Structure Length
- 28.7 m (94 ft)
- Deck Width
- 5.6 m (18 ft)
- Owner
- Railroad
- Avg Daily Traffic
- 84 vehicles/day
- Structure Number
- 084R00604N
Condition Analysis
- • At 6/9, the deck (driving surface) shows fair condition, with minor wear flagged for upkeep.
- • The superstructure (beams and supports above the deck) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
- • At 5/9, the substructure (piers and abutments) shows fair condition, with minor wear flagged for upkeep.
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 ISON LN 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 ISON LN against other structures in Mercer and across Kentucky. Kentucky 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 ISON LN?
ISON LN in Mercer, Kentucky 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 ISON LN inspected?
ISON LN'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 84 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. ISON LN 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 ISON LN?
ISON LN has an NBI inventory load rating of 7.2 metric tons.
Who is responsible for maintaining ISON LN?
ISON LN is owned and maintained by Railroad.
How old is ISON LN and does age affect safety?
ISON LN was built in 1940, making it 86 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.
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.