BACKBONE ST PK
Carrying BACKBONE ST PK over MAQUOKETA RIVER
IN BACKBONE STATE PARK, Delaware, Iowa
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: BACKBONE ST PK
The BACKBONE ST PK bridge in Delaware, Iowa carries BACKBONE ST PK over MAQUOKETA RIVER. It was built in 1989, making it 37 years old today. The structure is built primarily of concrete continuous and spans 3 sections, stretching 31.4 meters (103 feet) end to end. Average daily traffic is not reported for this structure. It is owned and maintained by State Park/Forest/Reservation.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 7/9, substructure at 7/9. The weakest component sits in good condition. None of this bridge's reported major components fall into the Poor condition range. Its NBI inventory load rating is 49.4 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How BACKBONE ST PK compares
Live comparison across Iowa.
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 How the historical reference is calculated.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
- 1989
- Material
- Concrete Continuous
- Number of Spans
- 3
- Structure Length
- 31.4 m (103 ft)
- Deck Width
- 10.1 m (33 ft)
- Owner
- State Park/Forest/Reservation
- Structure Number
- 000000000699041
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) is in good condition (7/9), showing no significant deterioration.
- • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
- • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.
How to read this record
This page shows what the last federal inspection recorded, not whether BACKBONE ST PK 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 BACKBONE ST PK against other structures in Delaware and across Iowa. Iowa 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 BACKBONE ST PK?
BACKBONE ST PK in Delaware, Iowa has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is BACKBONE ST PK inspected?
BACKBONE ST PK's responsible agency sets its routine interval under FHWA's risk-based inspection rules; this page does not expose the scheduled interval.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. BACKBONE ST PK 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 BACKBONE ST PK?
BACKBONE ST PK has an NBI inventory load rating of 49.4 metric tons.
Who is responsible for maintaining BACKBONE ST PK?
BACKBONE ST PK is owned and maintained by State Park/Forest/Reservation.
How old is BACKBONE ST PK and does age affect safety?
BACKBONE ST PK was built in 1989, making it 37 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.