TR 317
Carrying TR 317 over CRI RR & IM CANAL
N.2755 E.1340, LaSalle, Illinois
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: TR 317
The TR 317 bridge in LaSalle, Illinois carries TR 317 over CRI RR & IM CANAL. It was built in 1978, making it 48 years old today. The structure is built primarily of steel continuous and spans 3 sections, stretching 106.7 meters (350 feet) end to end. Daily traffic averages 600 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 8/9, superstructure at 8/9, substructure at 5/9. 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 38.9 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How TR 317 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 How the historical reference is calculated.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
- 1978
- Material
- Steel Continuous
- Number of Spans
- 3
- Structure Length
- 106.7 m (350 ft)
- Deck Width
- 9.1 m (30 ft)
- Owner
- Town/Township Highway Agency
- Avg Daily Traffic
- 600 vehicles/day
- Structure Number
- 050345300000000
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) rates good at 8/9, with no significant deterioration on file.
- • The superstructure (beams and supports above the deck) rates good at 8/9, with no significant deterioration on file.
- • The substructure (piers and abutments) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
How to read this record
This page shows what the last federal inspection recorded, not whether TR 317 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 TR 317 against other structures in LaSalle 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 TR 317?
TR 317 in LaSalle, Illinois has a deck rating of 8/9, superstructure rating of 8/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.
How often is TR 317 inspected?
TR 317'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 600 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. TR 317 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 TR 317?
TR 317 has an NBI inventory load rating of 38.9 metric tons.
Who is responsible for maintaining TR 317?
TR 317 is owned and maintained by Town/Township Highway Agency.
How old is TR 317 and does age affect safety?
TR 317 was built in 1978, making it 48 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.