FHWA NBI 2024 Inspection record Public-domain dataset

15TH AVE

Carrying 15TH AVE over ROCK RIVER

0.01 M E OF MAIN, Winnebago, Illinois

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Poor
37 t Inventory load rating

Bridge Snapshot: 15TH AVE

The 15TH AVE bridge in Winnebago, Illinois carries 15TH AVE over ROCK RIVER. It was built in 1980, making it 46 years old today. The structure is built primarily of steel and spans 8 sections, stretching 161.2 meters (529 feet) end to end. Daily traffic averages 5,750 vehicles, placing it in the moderately-trafficked tier of Illinois bridges. It is owned and maintained by City/Municipal Highway Agency.

The latest FHWA inspection records show a deck rating of 5/9, superstructure at 4/9, substructure at 6/9. 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 37.3 metric tons.

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

How 15TH AVE compares

▲ 2.7
Load rating vs Illinois average (34.6 t)
Top 25%
Higher load rating than 75% of Illinois bridges
475
Bridges in Winnebago · 29 in Poor condition
15TH AVE 37.3 t
Illinois average 34.6 t

Live comparison across Illinois.

Historical Sufficiency Rating

PlainBridge-computed
52.9 / 100 - historical 50–79.9 band
Structural adequacy /55
30.0
Serviceability /30
11.0
Essentiality /15
13.9
Special reductions
−2.0

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 How the historical reference is calculated.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
4/9
Poor (1–4)
Substructure
6/9
Fair (5–6)
Inventory Load Rating
37.3 t
NBI inventory level (metric tons)
Overall Condition
Poor

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

Structural Details

Year Built
1980
Material
Steel
Number of Spans
8
Structure Length
161.2 m (529 ft)
Deck Width
23.2 m (76 ft)
Owner
City/Municipal Highway Agency
Avg Daily Traffic
5,750 vehicles/day
Structure Number
101613700000000

Condition Analysis

  • At 5/9, the deck (driving surface) shows fair condition, with minor wear flagged for upkeep.
  • At 4/9, the superstructure (beams and supports above the deck) is in poor shape, with advanced wear flagged for priority repair.
  • At 6/9, the substructure (piers and abutments) shows fair condition, with minor wear flagged for upkeep.

How to read this record

15TH AVE 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 15TH AVE against other structures in Winnebago and across Illinois. Illinois 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 15TH AVE?

15TH AVE in Winnebago, Illinois has a deck rating of 5/9, superstructure rating of 4/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.

How often is 15TH AVE inspected?

15TH AVE'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 5,750 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. 15TH AVE 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 15TH AVE?

15TH AVE has an NBI inventory load rating of 37.3 metric tons.

Who is responsible for maintaining 15TH AVE?

15TH AVE is owned and maintained by City/Municipal Highway Agency.

How old is 15TH AVE and does age affect safety?

15TH AVE was built in 1980, making it 46 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.