OAK KNOLL ROAD
Carrying OAK KNOLL ROAD over SPRING VALLEY CREEK
008 W STATE HWY 221, Polk, Oregon
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
OAK KNOLL ROAD in Polk, Oregon sits above 69% of rated Oregon bridges on inventory load rating (37 t), while its 1966 build year is earlier than 57% of Polk's recorded-year cohort (161 bridges).
OAK KNOLL ROAD in Polk, Oregon is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1966, it carries 3 rated components 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 OR:53C050063500091
INTERSTATE-ERA · PRESTRESS · MULTI-SPAN · SUB-LED · LOCAL-ADT · STANDARD-LOAD · CAT-FAIR
- INTERSTATE-ERA 1950–1979
- PRESTRESS Prestressed concrete
- MULTI-SPAN 2 spans
- SUB-LED Substructure-led
- LOCAL-ADT Local ADT
- STANDARD-LOAD Standard 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: OAK KNOLL ROAD
The OAK KNOLL ROAD bridge in Polk, Oregon carries OAK KNOLL ROAD over SPRING VALLEY CREEK. It was built in 1966, making it 60 years old today. The structure is built primarily of prestressed concrete and spans 2 sections, stretching 17.1 meters (56 feet) end to end. Daily traffic averages 109 vehicles, placing it in the lower-traffic tier of Oregon bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 7/9, substructure at 6/9. The weakest component sits in fair condition. All reported major components score above the Poor range.
How OAK KNOLL ROAD compares
Age against the county: built in 1966, earlier than 92 of Polk's 161 bridges with a recorded construction year (57%), against a county median build year of 1974. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Oregon bridges with a recorded inventory load rating (8,282 of 8,305 rated).
OAK KNOLL ROAD vs every rated Oregon bridge
Inventory load rating (metric tons), FHWA NBI, this state
37 Top 31% higher than 69% of 8,282 bridges
rated Oregon 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.
Polk inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 161 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
- 1966
- Material
- Prestressed Concrete
- Number of Spans
- 2
- Structure Length
- 17.1 m (56 ft)
- Deck Width
- 6.4 m (21 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 109 vehicles/day
- Structure Number
- 53C050063500091
Condition Analysis
- • The deck (driving surface) is in good condition (7/9), showing no significant deterioration.
- • The superstructure (beams and supports above the deck) is in good condition (7/9), showing no significant deterioration.
- • The substructure (piers and abutments) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
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 OAK KNOLL ROAD 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 OAK KNOLL ROAD against other structures in Polk and across Oregon. Oregon 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 OAK KNOLL ROAD?
OAK KNOLL ROAD in Polk, Oregon has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is OAK KNOLL ROAD inspected?
OAK KNOLL ROAD'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 109 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. OAK KNOLL ROAD 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 OAK KNOLL ROAD?
OAK KNOLL ROAD has an NBI inventory load rating of 37.2 metric tons.
Who is responsible for maintaining OAK KNOLL ROAD?
OAK KNOLL ROAD is owned and maintained by County Highway Agency.
How old is OAK KNOLL ROAD and does age affect safety?
OAK KNOLL ROAD was built in 1966, making it 60 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.