FHWA NBI 2024 Inspection record Public-domain dataset

FAS-393(CH-4)

Carrying FAS-393(CH-4) over Trib to Walnut Creek

W.CTR-17-T13N,R4E, Knox, Illinois

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
33 t Inventory load rating

Bridge Snapshot: FAS-393(CH-4)

The FAS-393(CH-4) bridge in Knox, Illinois carries FAS-393(CH-4) over Trib to Walnut Creek. It was built in 1983, making it 43 years old today. The structure is built primarily of prestressed concrete and spans 1 section, stretching 16.9 meters (55 feet) end to end. Daily traffic averages 600 vehicles, placing it in the lower-traffic tier of Illinois bridges. It is owned and maintained by County Highway Agency.

The latest FHWA inspection records show a deck rating of 5/9, superstructure at 5/9, substructure at 7/9. The weakest component sits in fair condition. All reported major components score above the Poor range. Its NBI inventory load rating is 33.0 metric tons.

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

How FAS-393(CH-4) compares

▼ 1.6
Load rating vs Illinois average (34.6 t)
Top 34%
Higher load rating than 66% of Illinois bridges
321
Bridges in Knox · 19 in Poor condition
FAS-393(CH-4) 33.0 t
Illinois average 34.6 t

Live comparison across Illinois.

Historical Sufficiency Rating

PlainBridge-computed
86.0 / 100 - historical 80–100 band
Structural adequacy /55
45.0
Serviceability /30
26.2
Essentiality /15
14.8
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 How the historical reference is calculated.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
5/9
Fair (5–6)
Substructure
7/9
Good (7–9)
Inventory Load Rating
33.0 t
NBI inventory level (metric tons)
Overall Condition
Fair

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

Structural Details

Year Built
1983
Material
Prestressed Concrete
Number of Spans
1
Structure Length
16.9 m (55 ft)
Deck Width
8.5 m (28 ft)
Owner
County Highway Agency
Avg Daily Traffic
600 vehicles/day
Structure Number
048327700000000

Condition Analysis

  • The deck (driving surface) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
  • The superstructure (beams and supports above the deck) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
  • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.

How to read this record

This page shows what the last federal inspection recorded, not whether FAS-393(CH-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 FAS-393(CH-4) against other structures in Knox 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 FAS-393(CH-4)?

FAS-393(CH-4) in Knox, Illinois has a deck rating of 5/9, superstructure rating of 5/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.

How often is FAS-393(CH-4) inspected?

FAS-393(CH-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 600 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. FAS-393(CH-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 FAS-393(CH-4)?

FAS-393(CH-4) has an NBI inventory load rating of 33.0 metric tons.

Who is responsible for maintaining FAS-393(CH-4)?

FAS-393(CH-4) is owned and maintained by County Highway Agency.

How old is FAS-393(CH-4) and does age affect safety?

FAS-393(CH-4) was built in 1983, making it 43 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.