ILL 158
Carrying ILL 158 over LOOP CREEK
0.3 M N JCT ILL 177, St. Clair, Illinois
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: ILL 158
The ILL 158 bridge in St. Clair, Illinois carries ILL 158 over LOOP CREEK. It was built in 1923, making it 103 years old today. It was last reconstructed in 1983, extending its service life. The structure is built primarily of prestressed concrete and spans 1 section, stretching 14.9 meters (49 feet) end to end. Daily traffic averages 5,350 vehicles, placing it in the moderately-trafficked tier of Illinois bridges. It is owned and maintained by State 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 ILL 158 compares
Live comparison across Illinois.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 1923
- Last Reconstructed
- 1983
- Material
- Prestressed Concrete
- Number of Spans
- 1
- Structure Length
- 14.9 m (49 ft)
- Deck Width
- 10.1 m (33 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 5,350 vehicles/day
- Structure Number
- 082013300000000
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • At 5/9, the deck (driving surface) shows fair condition, with minor wear flagged for upkeep.
- • 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 ILL 158 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 158 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 158?
ILL 158 in St. Clair, 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 ILL 158 inspected?
ILL 158'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 5,350 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. ILL 158 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 ILL 158?
ILL 158 has an NBI inventory load rating of 33.0 metric tons.
Who is responsible for maintaining ILL 158?
ILL 158 is owned and maintained by State Highway Agency.
How old is ILL 158 and does age affect safety?
ILL 158 was built in 1923, making it 103 years old and last reconstructed in 1983.
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.
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.