IRR N4670
Carrying IRR N4670 over SYCAMORE CREEK
N4685E0150007, Ottawa, Oklahoma
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: IRR N4670
The IRR N4670 bridge in Ottawa, Oklahoma carries IRR N4670 over SYCAMORE CREEK. It was built in 1985, making it 41 years old today. The structure is built primarily of steel and spans 3 sections, stretching 28.0 meters (92 feet) end to end. Daily traffic averages 100 vehicles, placing it in the lower-traffic tier of Oklahoma bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 5/9, superstructure at 6/9, substructure at 3/9. 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 40.2 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How IRR N4670 compares
Live comparison across Oklahoma.
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 How the historical reference is calculated.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
- 1985
- Material
- Steel
- Number of Spans
- 3
- Structure Length
- 28.0 m (92 ft)
- Deck Width
- 6.3 m (21 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 100 vehicles/day
- Structure Number
- 210300000000000
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • At 6/9, the superstructure (beams and supports above the deck) shows fair condition, with minor wear flagged for upkeep.
- • The substructure (piers and abutments) rates poor at 3/9, advanced deterioration that should be prioritized for repair.
How to read this record
IRR N4670 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 IRR N4670 against other structures in Ottawa and across Oklahoma. Oklahoma 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 IRR N4670?
IRR N4670 in Ottawa, Oklahoma has a deck rating of 5/9, superstructure rating of 6/9, and substructure rating of 3/9 on the FHWA's 0–9 scale.
How often is IRR N4670 inspected?
IRR N4670'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 100 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. IRR N4670 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 IRR N4670?
IRR N4670 has an NBI inventory load rating of 40.2 metric tons.
Who is responsible for maintaining IRR N4670?
IRR N4670 is owned and maintained by County Highway Agency.
How old is IRR N4670 and does age affect safety?
IRR N4670 was built in 1985, making it 41 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.