FHWA NBI 2024 Inspection record Public-domain dataset

ILL 161

Carrying ILL 161 over TRIB TO LOOP CREEK

1.22 M W OF ILL 158, St. Clair, Illinois

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Good
40 t Inventory load rating

Bridge Snapshot: ILL 161

The ILL 161 bridge in St. Clair, Illinois carries ILL 161 over TRIB TO LOOP CREEK. It was built in 1933, making it 93 years old today. It was last reconstructed in 1975, extending its service life. The structure is built primarily of concrete continuous and spans 2 sections, stretching 8.4 meters (28 feet) end to end. Daily traffic averages 14,400 vehicles, placing it in the heavily-trafficked tier of Illinois bridges. It is owned and maintained by State Highway Agency.

The latest FHWA inspection records show culvert at 7/9. The weakest component sits in good condition. None of this bridge's reported major components fall into the Poor condition range. Its NBI inventory load rating is 39.9 metric tons.

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

How ILL 161 compares

▲ 5.3
Load rating vs Illinois average (34.6 t)
Top 19%
Higher load rating than 81% of Illinois bridges
502
Bridges in St. Clair · 40 in Poor condition
ILL 161 39.9 t
Illinois average 34.6 t

Live comparison across Illinois.

Historical Sufficiency Rating

PlainBridge-computed
73.5 / 100 - historical 50–79.9 band
Structural adequacy /55
55.0
Serviceability /30
15.0
Essentiality /15
3.5
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 How the historical reference is calculated.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

Culvert
7/9
Good (7–9)
Inventory Load Rating
39.9 t
NBI inventory level (metric tons)
Overall Condition
Good

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

Structural Details

Year Built
1933
Last Reconstructed
1975
Material
Concrete Continuous
Number of Spans
2
Structure Length
8.4 m (28 ft)
Owner
State Highway Agency
Avg Daily Traffic
14,400 vehicles/day
Structure Number
082200700000000

How to read this record

This page shows what the last federal inspection recorded, not whether ILL 161 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 ILL 161 against other structures in St. Clair 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 ILL 161?

ILL 161 in St. Clair, Illinois on the FHWA's 0–9 scale.

How often is ILL 161 inspected?

ILL 161'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 14,400 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. ILL 161 is currently shown as Good condition from its component ratings; that category is not a live closure or safety decision.

What is the inventory load rating for ILL 161?

ILL 161 has an NBI inventory load rating of 39.9 metric tons.

Who is responsible for maintaining ILL 161?

ILL 161 is owned and maintained by State Highway Agency.

How old is ILL 161 and does age affect safety?

ILL 161 was built in 1933, making it 93 years old and last reconstructed in 1975.

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.