FHWA NBI 2024 Inspection record Public-domain dataset

DUPLECHAIN RD

Carrying DUPLECHAIN RD over MULBERRY CREEK

0.4 MI E OF C-CASTOR RD., Allen, Louisiana

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
19 t Inventory load rating

Bridge Snapshot: DUPLECHAIN RD

The DUPLECHAIN RD bridge in Allen, Louisiana carries DUPLECHAIN RD over MULBERRY CREEK. It was built in 1997, making it 29 years old today. The structure is built primarily of concrete and spans 3 sections, stretching 17.4 meters (57 feet) end to end. Daily traffic averages 105 vehicles, placing it in the lower-traffic tier of Louisiana 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. All reported major components score above the Poor range. Its NBI inventory load rating is 18.5 metric tons.

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

How DUPLECHAIN RD compares

▼ 13.8
Load rating vs Louisiana average (32.3 t)
Bottom 13%
Lower load rating than 87% of Louisiana bridges
178
Bridges in Allen · 22 in Poor condition
DUPLECHAIN RD 18.5 t
Louisiana average 32.3 t

Live comparison across Louisiana.

Historical Sufficiency Rating

PlainBridge-computed
75.8 / 100 - historical 50–79.9 band
Structural adequacy /55
38.1
Serviceability /30
22.8
Essentiality /15
14.9
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 How the historical reference is calculated.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
6/9
Fair (5–6)
Superstructure
6/9
Fair (5–6)
Substructure
6/9
Fair (5–6)
Inventory Load Rating
18.5 t
NBI inventory level (metric tons)
Overall Condition
Fair

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

Structural Details

Year Built
1997
Material
Concrete
Number of Spans
3
Structure Length
17.4 m (57 ft)
Deck Width
8.2 m (27 ft)
Owner
County Highway Agency
Avg Daily Traffic
105 vehicles/day
Structure Number
070230377923681

Condition Analysis

  • At 6/9, 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 (6/9), with minor deterioration that may require routine maintenance.
  • The substructure (piers and abutments) is in fair condition (6/9), with minor deterioration that may require routine maintenance.

How to read this record

This page shows what the last federal inspection recorded, not whether DUPLECHAIN RD 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 DUPLECHAIN RD against other structures in Allen and across Louisiana. Louisiana 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 DUPLECHAIN RD?

DUPLECHAIN RD in Allen, Louisiana 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 DUPLECHAIN RD inspected?

DUPLECHAIN RD'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 105 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. DUPLECHAIN RD 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 DUPLECHAIN RD?

DUPLECHAIN RD has an NBI inventory load rating of 18.5 metric tons.

Who is responsible for maintaining DUPLECHAIN RD?

DUPLECHAIN RD is owned and maintained by County Highway Agency.

How old is DUPLECHAIN RD and does age affect safety?

DUPLECHAIN RD was built in 1997, making it 29 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.