FHWA NBI 2024 Inspection record Public-domain dataset

B46

Carrying B46 over NO NAME CREEK

095472101, Sioux, Iowa

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Poor
30 t Inventory load rating

Bridge Snapshot: B46

The B46 bridge in Sioux, Iowa carries B46 over NO NAME CREEK. It was built in 1966, making it 60 years old today. The structure is built primarily of steel and spans 1 section, stretching 13.4 meters (44 feet) end to end. Daily traffic averages 538 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 5/9, superstructure at 6/9, substructure at 4/9. 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 30.1 metric tons.

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

How B46 compares

▼ 0.8
Load rating vs Iowa average (30.9 t)
Bottom 45%
Lower load rating than 55% of Iowa bridges
429
Bridges in Sioux · 10 in Poor condition
B46 30.1 t
Iowa average 30.9 t

Live comparison across Iowa.

Historical Sufficiency Rating

PlainBridge-computed
63.9 / 100 - historical 50–79.9 band
Structural adequacy /55
28.9
Serviceability /30
20.2
Essentiality /15
14.9
Special reductions
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 How the historical reference is calculated.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

Deck
5/9
Fair (5–6)
Superstructure
6/9
Fair (5–6)
Substructure
4/9
Poor (1–4)
Inventory Load Rating
30.1 t
NBI inventory level (metric tons)
Overall Condition
Poor

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

Structural Details

Year Built
1966
Material
Steel
Number of Spans
1
Structure Length
13.4 m (44 ft)
Deck Width
9.1 m (30 ft)
Owner
County Highway Agency
Avg Daily Traffic
538 vehicles/day
Structure Number
000000000310850

Condition Analysis

  • The deck (driving surface) rates fair at 5/9, minor deterioration that routine maintenance should address.
  • The superstructure (beams and supports above the deck) rates fair at 6/9, minor deterioration that routine maintenance should address.
  • The substructure (piers and abutments) rates poor at 4/9, advanced deterioration that should be prioritized for repair.

How to read this record

B46 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 B46 against other structures in Sioux 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 B46?

B46 in Sioux, Iowa has a deck rating of 5/9, superstructure rating of 6/9, and substructure rating of 4/9 on the FHWA's 0–9 scale.

How often is B46 inspected?

B46'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 538 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. B46 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 B46?

B46 has an NBI inventory load rating of 30.1 metric tons.

Who is responsible for maintaining B46?

B46 is owned and maintained by County Highway Agency.

How old is B46 and does age affect safety?

B46 was built in 1966, making it 60 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.