NW21
Carrying NW21 over DEVILS BR POST OAK
S 11 T 46 N R 26 W, Johnson, Missouri
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
NW21 in Johnson, Missouri sits above 2% of rated Missouri bridges on inventory load rating (5 t), while its 1926 build year is earlier than 80% of Johnson's recorded-year cohort (476 bridges).
NW21 in Johnson, Missouri is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1926, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 3. 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 MO:33817
PRE-1950 · STEEL · SINGLE-SPAN · SUPER-LED · TRACE-ADT · LIGHT-LOAD · CAT-POOR
- PRE-1950 Pre-1950
- STEEL Steel
- SINGLE-SPAN Single span
- SUPER-LED Superstructure-led
- TRACE-ADT Trace ADT
- LIGHT-LOAD Light 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.
Bridge Snapshot: NW21
The NW21 bridge in Johnson, Missouri carries NW21 over DEVILS BR POST OAK. It was built in 1926, making it 100 years old today. The structure is built primarily of steel and spans 1 section, stretching 46.9 meters (154 feet) end to end. Daily traffic averages 5 vehicles, placing it in the lower-traffic tier of Missouri bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 4/9, superstructure at 3/9, substructure at 5/9. The weakest component sits in poor condition. Because at least one major component scores 4 or lower, this bridge falls in FHWA's Poor condition category. That category is not a closure order.
How NW21 compares
Age against the county: built in 1926, earlier than 379 of Johnson's 476 bridges with a recorded construction year (80%), against a county median build year of 1992. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Missouri bridges with a recorded inventory load rating (24,616 of 24,618 rated).
NW21 vs every rated Missouri bridge
Inventory load rating (metric tons), FHWA NBI, this state
5 Top 98% higher than 2% of 24,616 bridges
rated Missouri 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.
Johnson inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 476 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
- 1926
- Material
- Steel
- Number of Spans
- 1
- Structure Length
- 46.9 m (154 ft)
- Deck Width
- 6.6 m (22 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 5 vehicles/day
- Structure Number
- 33817
Condition Analysis
- • The deck (driving surface) rates poor at 4/9, with advanced deterioration recorded on the latest inspection.
- • At 3/9, 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) 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
NW21 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 NW21 against other structures in Johnson and across Missouri. Missouri 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 NW21?
NW21 in Johnson, Missouri has a deck rating of 4/9, superstructure rating of 3/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.
How often is NW21 inspected?
NW21'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 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. NW21 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 NW21?
NW21 has an NBI inventory load rating of 4.5 metric tons.
Who is responsible for maintaining NW21?
NW21 is owned and maintained by County Highway Agency.
How old is NW21 and does age affect safety?
NW21 was built in 1926, making it 100 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.