DERBY AVE SW
Carrying DERBY AVE SW over STREAM
078083402, Johnson, Iowa
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: DERBY AVE SW
The DERBY AVE SW bridge in Johnson, Iowa carries DERBY AVE SW over STREAM. It was built in 1954, making it 72 years old today. The structure is built primarily of wood or timber and spans 1 section, stretching 6.1 meters (20 feet) end to end. Daily traffic averages 60 vehicles, placing it in the lower-traffic tier of Iowa bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 4/9, superstructure at 5/9, substructure at 3/9. The weakest component sits in poor condition. At least one major component here scores 4 or below, which produces a Poor condition classification under FHWA's current reporting rules. Its NBI inventory load rating is 2.7 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How DERBY AVE SW compares
Live comparison across Iowa.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 1954
- Material
- Wood or Timber
- Number of Spans
- 1
- Structure Length
- 6.1 m (20 ft)
- Deck Width
- 6.1 m (20 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 60 vehicles/day
- Structure Number
- 000000000203860
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • At 4/9, the deck (driving surface) is in poor shape, with advanced wear flagged for priority repair.
- • At 5/9, the superstructure (beams and supports above the deck) shows fair condition, with minor wear flagged for upkeep.
- • At 3/9, the substructure (piers and abutments) is in poor shape, with advanced wear flagged for priority repair.
How to read this record
DERBY AVE SW 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 DERBY AVE SW against other structures in Johnson and across Iowa. Iowa 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 DERBY AVE SW?
DERBY AVE SW in Johnson, Iowa has a deck rating of 4/9, superstructure rating of 5/9, and substructure rating of 3/9 on the FHWA's 0–9 scale.
How often is DERBY AVE SW inspected?
DERBY AVE SW'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 60 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. DERBY AVE SW 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 DERBY AVE SW?
DERBY AVE SW has an NBI inventory load rating of 2.7 metric tons.
Who is responsible for maintaining DERBY AVE SW?
DERBY AVE SW is owned and maintained by County Highway Agency.
How old is DERBY AVE SW and does age affect safety?
DERBY AVE SW was built in 1954, making it 72 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.
Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.