FHWA NBI 2024 Inspection record Public-domain dataset

GRANITE AVE

Carrying GRANITE AVE over BROKEN KETTLE CREEK

093472202, Plymouth, Iowa

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Poor
16 t Inventory load rating

Bridge Snapshot: GRANITE AVE

The GRANITE AVE bridge in Plymouth, Iowa carries GRANITE AVE over BROKEN KETTLE CREEK. It was built in 1959, making it 67 years old today. The structure is built primarily of steel and spans 1 section, stretching 7.6 meters (25 feet) end to end. Daily traffic averages 20 vehicles, placing it in the lower-traffic tier of Iowa bridges. It is owned and maintained by County Highway Agency.

The latest FHWA inspection records show a deck rating of 7/9, superstructure at 6/9, substructure at 4/9. The weakest component sits in poor condition. Because at least one major component scores 4 or lower, this bridge falls in FHWA's Poor condition category. That category is not a closure order. Its NBI inventory load rating is 16.3 metric tons.

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

How GRANITE AVE compares

▼ 14.6
Load rating vs Iowa average (30.9 t)
Bottom 11%
Lower load rating than 89% of Iowa bridges
407
Bridges in Plymouth · 90 in Poor condition
GRANITE AVE 16.3 t
Iowa average 30.9 t

Live comparison across Iowa.

Historical Sufficiency Rating

PlainBridge-computed
46.0 / 100 - historical 20–49.9 band
Structural adequacy /55
9.0
Serviceability /30
22.0
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 How the historical reference is calculated.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
6/9
Fair (5–6)
Substructure
4/9
Poor (1–4)
Inventory Load Rating
16.3 t
NBI inventory level (metric tons)
Overall Condition
Poor

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

Structural Details

Year Built
1959
Material
Steel
Number of Spans
1
Structure Length
7.6 m (25 ft)
Deck Width
6.2 m (20 ft)
Owner
County Highway Agency
Avg Daily Traffic
20 vehicles/day
Structure Number
000000000277380

Condition Analysis

  • The deck (driving surface) rates good at 7/9, with no significant deterioration on file.
  • The superstructure (beams and supports above the deck) rates fair at 6/9, minor deterioration that routine maintenance should address.
  • The substructure (piers and abutments) is in poor condition (4/9), showing advanced deterioration that may require priority repair.

How to read this record

GRANITE AVE 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 GRANITE AVE against other structures in Plymouth 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 GRANITE AVE?

GRANITE AVE in Plymouth, Iowa has a deck rating of 7/9, superstructure rating of 6/9, and substructure rating of 4/9 on the FHWA's 0–9 scale.

How often is GRANITE AVE inspected?

GRANITE AVE'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 20 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. GRANITE AVE 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 GRANITE AVE?

GRANITE AVE has an NBI inventory load rating of 16.3 metric tons.

Who is responsible for maintaining GRANITE AVE?

GRANITE AVE is owned and maintained by County Highway Agency.

How old is GRANITE AVE and does age affect safety?

GRANITE AVE was built in 1959, making it 67 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.