NFA D917
Carrying NFA D917 over STOCK CREEK
TIPTON STA. RD-S OF SR168, Knox, Tennessee
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
NFA D917 in Knox, Tennessee sits above 39% of rated Tennessee bridges on inventory load rating (32 t), while its 1915 build year is earlier than 99% of Knox's recorded-year cohort (588 bridges).
NFA D917 in Knox, Tennessee is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1915, 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 TN:470D9170001
PRE-1950 · CONCRETE · MULTI-SPAN · TIED-CTRL · LOCAL-ADT · STANDARD-LOAD · CAT-FAIR
- PRE-1950 Pre-1950
- CONCRETE Concrete
- MULTI-SPAN 2 spans
- TIED-CTRL Tied control
- LOCAL-ADT Local 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.
Bridge Snapshot: NFA D917
The NFA D917 bridge in Knox, Tennessee carries NFA D917 over STOCK CREEK. It was built in 1915, making it 111 years old today. The structure is built primarily of concrete and spans 2 sections, stretching 8.8 meters (29 feet) end to end. Daily traffic averages 710 vehicles, placing it in the lower-traffic tier of Tennessee bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 5/9, superstructure at 5/9, substructure at 5/9. The weakest component sits in fair condition. All reported major components score above the Poor range.
How NFA D917 compares
Age against the county: built in 1915, earlier than 581 of Knox's 588 bridges with a recorded construction year (99%), against a county median build year of 1973. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Tennessee bridges with a recorded inventory load rating (20,355 of 20,379 rated).
NFA D917 vs every rated Tennessee bridge
Inventory load rating (metric tons), FHWA NBI, this state
32 Top 61% higher than 39% of 20,355 bridges
rated Tennessee 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.
Knox inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 588 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
- 1915
- Material
- Concrete
- Number of Spans
- 2
- Structure Length
- 8.8 m (29 ft)
- Deck Width
- 4.9 m (16 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 710 vehicles/day
- Structure Number
- 470D9170001
Condition Analysis
- • The deck (driving surface) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • At 5/9, the superstructure (beams and supports above the deck) shows fair condition, with minor wear flagged for upkeep.
- • The substructure (piers and abutments) is in fair condition (5/9), 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 NFA D917 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 NFA D917 against other structures in Knox and across Tennessee. Tennessee 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 NFA D917?
NFA D917 in Knox, Tennessee has a deck rating of 5/9, superstructure rating of 5/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.
How often is NFA D917 inspected?
NFA D917'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 710 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. NFA D917 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 NFA D917?
NFA D917 has an NBI inventory load rating of 32.4 metric tons.
Who is responsible for maintaining NFA D917?
NFA D917 is owned and maintained by County Highway Agency.
How old is NFA D917 and does age affect safety?
NFA D917 was built in 1915, making it 111 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.