FHWA NBI 2024 Inspection record Public-domain dataset

NB US 75

Carrying NB US 75 over FLAT CREEK

1.2 mi. S of SR C44, Plymouth, Iowa

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
14 t Inventory load rating

Bridge Snapshot: NB US 75

The NB US 75 bridge in Plymouth, Iowa carries NB US 75 over FLAT CREEK. It was built in 1972, making it 54 years old today. The structure is built primarily of concrete continuous and spans 2 sections, stretching 8.2 meters (27 feet) end to end. Daily traffic averages 7,000 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 5/9. The weakest component sits in fair condition. None of this bridge's reported major components fall into the Poor condition range. Its NBI inventory load rating is 13.8 metric tons.

Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.

How NB US 75 compares

▼ 17.1
Load rating vs Iowa average (30.9 t)
Bottom 7%
Lower load rating than 93% of Iowa bridges
407
Bridges in Plymouth · 90 in Poor condition
NB US 75 13.8 t
Iowa average 30.9 t

Live comparison across Iowa.

Historical Sufficiency Rating

PlainBridge-computed
57.7 / 100 - historical 50–79.9 band
Structural adequacy /55
18.9
Serviceability /30
26.0
Essentiality /15
13.8
Special reductions
−1.0

FHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.

Condition Ratings

Culvert
5/9
Fair (5–6)
Inventory Load Rating
13.8 t
NBI inventory level (metric tons)
Overall Condition
Fair

Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.

Structural Details

Year Built
1972
Material
Concrete Continuous
Number of Spans
2
Structure Length
8.2 m (27 ft)
Deck Width
13.8 m (45 ft)
Owner
State Highway Agency
Avg Daily Traffic
7,000 vehicles/day
Structure Number
000000000039581

How to read this record

This page shows what the last federal inspection recorded, not whether NB US 75 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 NB US 75 against other structures in Plymouth 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 NB US 75?

NB US 75 in Plymouth, Iowa on the FHWA's 0–9 scale.

How often is NB US 75 inspected?

NB US 75'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 7,000 vehicles per day.

What does “structurally deficient” mean in older bridge reports?

FHWA retired that reported status beginning with the 2018 archive. NB US 75 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 NB US 75?

NB US 75 has an NBI inventory load rating of 13.8 metric tons.

Who is responsible for maintaining NB US 75?

NB US 75 is owned and maintained by State Highway Agency.

How old is NB US 75 and does age affect safety?

NB US 75 was built in 1972, making it 54 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.

Data sourced from the Federal Highway Administration National Bridge Inventory. See our methodology for details. Retrieved and formatted by PlainBridges

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.