FHWA NBI 2024 Inspection record Public-domain dataset

DENNY ROAD

Carrying DENNY ROAD over PISCASAW CREEK

2.5 SE POPLAR GROVE, Boone, Illinois

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Poor
28 t Inventory load rating

Bridge Snapshot: DENNY ROAD

The DENNY ROAD bridge in Boone, Illinois carries DENNY ROAD over PISCASAW CREEK. It was built in 1977, making it 49 years old today. The structure is built primarily of concrete and spans 4 sections, stretching 37.1 meters (122 feet) end to end. Daily traffic averages 50 vehicles, placing it in the lower-traffic tier of Illinois bridges. It is owned and maintained by Town/Township Highway Agency.

The latest FHWA inspection records show a deck rating of 7/9, superstructure at 3/9, substructure at 5/9. The weakest component sits in poor condition. At least one major component here scores 4 or below, which produces a Poor condition classification under FHWA's current reporting rules. Its NBI inventory load rating is 27.5 metric tons.

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

How DENNY ROAD compares

▼ 7.1
Load rating vs Illinois average (34.6 t)
Bottom 17%
Lower load rating than 83% of Illinois bridges
111
Bridges in Boone · 7 in Poor condition
DENNY ROAD 27.5 t
Illinois average 34.6 t

Live comparison across Illinois.

Historical Sufficiency Rating

PlainBridge-computed
47.4 / 100 - historical 20–49.9 band
Structural adequacy /55
11.5
Serviceability /30
21.0
Essentiality /15
15.0
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 How the historical reference is calculated.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
7/9
Good (7–9)
Superstructure
3/9
Poor (1–4)
Substructure
5/9
Fair (5–6)
Inventory Load Rating
27.5 t
NBI inventory level (metric tons)
Overall Condition
Poor

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

Structural Details

Year Built
1977
Material
Concrete
Number of Spans
4
Structure Length
37.1 m (122 ft)
Deck Width
8.0 m (26 ft)
Owner
Town/Township Highway Agency
Avg Daily Traffic
50 vehicles/day
Structure Number
004306800000000

Condition Analysis

  • At 7/9, the deck (driving surface) is in good shape and shows no significant wear.
  • The superstructure (beams and supports above the deck) is in poor condition (3/9), showing advanced deterioration that may require priority repair.
  • The substructure (piers and abutments) is in fair condition (5/9), with minor deterioration that may require routine maintenance.

How to read this record

DENNY ROAD is in the federal Poor condition category. That is a component-based result, not a closure order.

  • NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
  • Understand what Poor condition does and does not mean before drawing conclusions. Poor condition explained
  • Compare DENNY ROAD against other structures in Boone 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 DENNY ROAD?

DENNY ROAD in Boone, Illinois has a deck rating of 7/9, superstructure rating of 3/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.

How often is DENNY ROAD inspected?

DENNY ROAD'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 50 vehicles per day.

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

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

What is the inventory load rating for DENNY ROAD?

DENNY ROAD has an NBI inventory load rating of 27.5 metric tons.

Who is responsible for maintaining DENNY ROAD?

DENNY ROAD is owned and maintained by Town/Township Highway Agency.

How old is DENNY ROAD and does age affect safety?

DENNY ROAD was built in 1977, making it 49 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.