CH 18
Carrying CH 18 over TRIB OF MUD CREEK
W EDGE OF HENTON, Shelby, Illinois
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: CH 18
The CH 18 bridge in Shelby, Illinois carries CH 18 over TRIB OF MUD CREEK. It was built in 1961, making it 65 years old today. The structure is built primarily of prestressed concrete and spans 2 sections, stretching 24.5 meters (80 feet) end to end. Daily traffic averages 225 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 6/9, superstructure at 6/9, substructure at 6/9. The weakest component sits in fair condition. None of this bridge's reported major components fall into the Poor condition range. Its NBI inventory load rating is 41.5 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How CH 18 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 How the historical reference is calculated.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
- 1961
- Material
- Prestressed Concrete
- Number of Spans
- 2
- Structure Length
- 24.5 m (80 ft)
- Deck Width
- 8.4 m (28 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 225 vehicles/day
- Structure Number
- 087300800000000
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
- • At 6/9, the superstructure (beams and supports above the deck) shows fair condition, with minor wear flagged for upkeep.
- • The substructure (piers and abutments) rates fair at 6/9, minor deterioration that routine maintenance should address.
How to read this record
This page shows what the last federal inspection recorded, not whether CH 18 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 CH 18 against other structures in Shelby 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 CH 18?
CH 18 in Shelby, Illinois has a deck rating of 6/9, superstructure rating of 6/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is CH 18 inspected?
CH 18'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 225 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. CH 18 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 CH 18?
CH 18 has an NBI inventory load rating of 41.5 metric tons.
Who is responsible for maintaining CH 18?
CH 18 is owned and maintained by County Highway Agency.
How old is CH 18 and does age affect safety?
CH 18 was built in 1961, making it 65 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.
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.