500TH ST
Carrying 500TH ST over SILVER CREEK
500th West of Hazel, Shelby, Iowa
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
500TH ST in Shelby, Iowa sits above 24% of rated Iowa bridges on inventory load rating (22 t), while its 2017 build year is earlier than 7% of Shelby's recorded-year cohort (207 bridges).
500TH ST in Shelby, Iowa is rated Good in the FHWA's 2024 National Bridge Inventory. Built in 2017, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 7. The lowest applicable rating sets the federal condition category, so this Good result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure IA:000000000304721
POST-2000 · STEEL · MULTI-SPAN · TIED-CTRL · TRACE-ADT · STANDARD-LOAD · CAT-GOOD
- POST-2000 2000+
- STEEL Steel
- MULTI-SPAN 3 spans
- TIED-CTRL Tied control
- TRACE-ADT Trace ADT
- STANDARD-LOAD Standard load
- CAT-GOOD Good
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Structural health score
A composite of the deck, superstructure, and substructure NBI condition ratings plus the inventory load rating, benchmarked against the full national bridge corpus, distinct from the Good/Fair/Poor category above.
Bridge Snapshot: 500TH ST
The 500TH ST bridge in Shelby, Iowa carries 500TH ST over SILVER CREEK. It was built in 2017, making it 9 years old today. The structure is built primarily of steel and spans 3 sections, stretching 23.8 meters (78 feet) end to end. Daily traffic averages 15 vehicles, placing it in the lower-traffic tier of Iowa bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection places the weakest component in good condition (see the full component ratings below). None of this bridge's reported major components fall into the Poor condition range.
How 500TH ST compares
Age against the county: built in 2017, earlier than 14 of Shelby's 207 bridges with a recorded construction year (7%), against a county median build year of 1978. This is one of the newer structures in its county.
Live comparison across Iowa bridges with a recorded inventory load rating (23,718 of 23,719 rated).
500TH ST vs every rated Iowa bridge
Inventory load rating (metric tons), FHWA NBI, this state
22 Top 76% higher than 24% of 23,718 bridges
rated Iowa bridges, bucketed by value
Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FHWA National Bridge Inventory · August 2026
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.
Shelby inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 207 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 2017
- Material
- Steel
- Number of Spans
- 3
- Structure Length
- 23.8 m (78 ft)
- Deck Width
- 7.3 m (24 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 15 vehicles/day
- Structure Number
- 000000000304721
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) rates good at 7/9, with no significant deterioration on file.
- • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether 500TH ST 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 500TH ST against other structures in Shelby 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 500TH ST?
500TH ST in Shelby, 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 500TH ST inspected?
500TH ST'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 15 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. 500TH ST 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 500TH ST?
500TH ST has an NBI inventory load rating of 21.7 metric tons.
Who is responsible for maintaining 500TH ST?
500TH ST is owned and maintained by County Highway Agency.
How old is 500TH ST and does age affect safety?
500TH ST was built in 2017, making it 9 years old.
Share this inspection record
Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.