320TH STREET
Carrying 320TH STREET over STREAM
076410904, Pottawattamie, Iowa
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: 320TH STREET
The 320TH STREET bridge in Pottawattamie, Iowa carries 320TH STREET over STREAM. It was built in 1976, making it 50 years old today. The structure is built primarily of wood or timber and spans 3 sections, stretching 21.3 meters (70 feet) end to end. Daily traffic averages 20 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 6/9, superstructure at 7/9, substructure at 5/9. The weakest component sits in fair condition. All reported major components score above the Poor range. Its NBI inventory load rating is 21.0 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How 320TH STREET 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 How the historical reference is calculated.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
- 1976
- Material
- Wood or Timber
- Number of Spans
- 3
- Structure Length
- 21.3 m (70 ft)
- Deck Width
- 5.8 m (19 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 20 vehicles/day
- Structure Number
- 000000000288331
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗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 good condition (7/9), showing no significant deterioration.
- • The substructure (piers and abutments) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
How to read this record
This page shows what the last federal inspection recorded, not whether 320TH STREET 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 320TH STREET against other structures in Pottawattamie 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 320TH STREET?
320TH STREET in Pottawattamie, Iowa has a deck rating of 6/9, superstructure rating of 7/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.
How often is 320TH STREET inspected?
320TH STREET'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 20 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. 320TH STREET 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 320TH STREET?
320TH STREET has an NBI inventory load rating of 21.0 metric tons.
Who is responsible for maintaining 320TH STREET?
320TH STREET is owned and maintained by County Highway Agency.
How old is 320TH STREET and does age affect safety?
320TH STREET was built in 1976, making it 50 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.