FM 310TH AVE
Carrying FM 310TH AVE over SMALL STREAM
088031004, Delaware, Iowa
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
FM 310TH AVE in Delaware, Iowa sits above 93% of rated Iowa bridges on inventory load rating (49 t), while its 1967 build year is earlier than 79% of Delaware's recorded-year cohort (293 bridges).
FM 310TH AVE in Delaware, Iowa is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1967, it carries 1 rated component on the inspecting agency's 0-9 scale, and its weakest reported component scores 6. The lowest applicable rating sets the federal condition category, so this Fair 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:000000000140420
INTERSTATE-ERA · CONCRETE · MULTI-SPAN · CULVERT-LED · ARTERIAL-ADT · HEAVY-LOAD · CAT-FAIR
- INTERSTATE-ERA 1950–1979
- CONCRETE Concrete
- MULTI-SPAN 2 spans
- CULVERT-LED Culvert-led
- ARTERIAL-ADT Arterial ADT
- HEAVY-LOAD Heavy load
- CAT-FAIR Fair
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Bridge Snapshot: FM 310TH AVE
The FM 310TH AVE bridge in Delaware, Iowa carries FM 310TH AVE over SMALL STREAM. It was built in 1967, making it 59 years old today. The structure is built primarily of concrete and spans 2 sections, stretching 7.9 meters (26 feet) end to end. Daily traffic averages 1,316 vehicles, placing it in the moderately-trafficked tier of Iowa bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show culvert at 6/9. The weakest component sits in fair condition. None of this bridge's reported major components fall into the Poor condition range.
How FM 310TH AVE compares
Age against the county: built in 1967, earlier than 232 of Delaware's 293 bridges with a recorded construction year (79%), against a county median build year of 1981. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Iowa bridges with a recorded inventory load rating (23,718 of 23,719 rated).
FM 310TH AVE vs every rated Iowa bridge
Inventory load rating (metric tons), FHWA NBI, this state
49 Top 7% higher than 93% 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.
Delaware inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 293 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
- 1967
- Material
- Concrete
- Number of Spans
- 2
- Structure Length
- 7.9 m (26 ft) 0
- Owner
- County Highway Agency
- Avg Daily Traffic
- 1,316 vehicles/day
- Structure Number
- 000000000140420
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 FM 310TH AVE 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 FM 310TH AVE 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 FM 310TH AVE?
FM 310TH AVE in Delaware, Iowa on the FHWA's 0–9 scale.
How often is FM 310TH AVE inspected?
FM 310TH 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 1,316 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. FM 310TH AVE 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 FM 310TH AVE?
FM 310TH AVE has an NBI inventory load rating of 49.0 metric tons.
Who is responsible for maintaining FM 310TH AVE?
FM 310TH AVE is owned and maintained by County Highway Agency.
How old is FM 310TH AVE and does age affect safety?
FM 310TH AVE was built in 1967, making it 59 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.
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.