COUNTY HIGHWAY 4
Carrying COUNTY HIGHWAY 4 over ZUMA CREEK
2 MI SW OF JOSLIN, Rock Island, Illinois
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
COUNTY HIGHWAY 4 in Rock Island, Illinois sits above 96% of rated Illinois bridges on inventory load rating (56 t), while its 1978 build year is earlier than 56% of Rock Island's recorded-year cohort (272 bridges).
COUNTY HIGHWAY 4 in Rock Island, Illinois is rated Good in the FHWA's 2024 National Bridge Inventory. Built in 1978, it carries 1 rated component on the inspecting agency's 0-9 scale, and its weakest reported component scores 7. The lowest applicable rating sets the federal condition category, so this Good result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure IL:081500700000000
INTERSTATE-ERA · CONCRETE · MULTI-SPAN · CULVERT-LED · LOCAL-ADT · HEAVY-LOAD · CAT-GOOD
- INTERSTATE-ERA 1950–1979
- CONCRETE Concrete
- MULTI-SPAN 2 spans
- CULVERT-LED Culvert-led
- LOCAL-ADT Local ADT
- HEAVY-LOAD Heavy load
- CAT-GOOD Good
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Structural health score
A composite of the deck, superstructure, and substructure NBI condition ratings plus the inventory load rating, benchmarked against the full national bridge corpus, distinct from the Good/Fair/Poor category above.
Bridge Snapshot: COUNTY HIGHWAY 4
The COUNTY HIGHWAY 4 bridge in Rock Island, Illinois carries COUNTY HIGHWAY 4 over ZUMA CREEK. It was built in 1978, making it 48 years old today. The structure is built primarily of concrete and spans 2 sections, stretching 7.9 meters (26 feet) end to end. Daily traffic averages 175 vehicles, placing it in the lower-traffic tier of Illinois bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection places the weakest component in good condition (see the full component ratings below). All reported major components score above the Poor range.
How COUNTY HIGHWAY 4 compares
Age against the county: built in 1978, earlier than 152 of Rock Island's 272 bridges with a recorded construction year (56%), against a county median build year of 1984. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Illinois bridges with a recorded inventory load rating (26,904 of 26,928 rated).
COUNTY HIGHWAY 4 vs every rated Illinois bridge
Inventory load rating (metric tons), FHWA NBI, this state
56 Top 4% higher than 96% of 26,904 bridges
rated Illinois bridges, bucketed by value
Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FHWA National Bridge Inventory · August 2026
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Rock Island inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 272 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 1978
- Material
- Concrete
- Number of Spans
- 2
- Structure Length
- 7.9 m (26 ft) 0
- Owner
- County Highway Agency
- Avg Daily Traffic
- 175 vehicles/day
- Structure Number
- 081500700000000
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether COUNTY HIGHWAY 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 COUNTY HIGHWAY 4 against other structures in Rock Island 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 COUNTY HIGHWAY 4?
COUNTY HIGHWAY 4 in Rock Island, Illinois on the FHWA's 0–9 scale.
How often is COUNTY HIGHWAY 4 inspected?
COUNTY HIGHWAY 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 175 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. COUNTY HIGHWAY 4 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 COUNTY HIGHWAY 4?
COUNTY HIGHWAY 4 has an NBI inventory load rating of 56.4 metric tons.
Who is responsible for maintaining COUNTY HIGHWAY 4?
COUNTY HIGHWAY 4 is owned and maintained by County Highway Agency.
How old is COUNTY HIGHWAY 4 and does age affect safety?
COUNTY HIGHWAY 4 was built in 1978, making it 48 years old.
Share this inspection record
Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.