IA 4
Carrying IA 4 over DRAINAGE DITCH #41
5.5 mi S of jct US 18, Palo Alto, Iowa
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: IA 4
The IA 4 bridge in Palo Alto, Iowa carries IA 4 over DRAINAGE DITCH #41. It was built in 2000, making it 26 years old today. The structure is built primarily of concrete continuous and spans 2 sections, stretching 7.6 meters (25 feet) end to end. Daily traffic averages 2,040 vehicles, placing it in the moderately-trafficked tier of Iowa bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show culvert at 6/9. The weakest component sits in fair condition. All reported major components score above the Poor range. Its NBI inventory load rating is 22.9 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How IA 4 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 How the historical reference is calculated.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
- 2000
- Material
- Concrete Continuous
- Number of Spans
- 2
- Structure Length
- 7.6 m (25 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 2,040 vehicles/day
- Structure Number
- 000000000606021
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 IA 4 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 IA 4 against other structures in Palo Alto 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 IA 4?
IA 4 in Palo Alto, Iowa on the FHWA's 0–9 scale.
How often is IA 4 inspected?
IA 4'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 2,040 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. IA 4 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 IA 4?
IA 4 has an NBI inventory load rating of 22.9 metric tons.
Who is responsible for maintaining IA 4?
IA 4 is owned and maintained by State Highway Agency.
How old is IA 4 and does age affect safety?
IA 4 was built in 2000, making it 26 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.