Hwy 81SB - Hwy 171
Carrying Hwy 81SB - Hwy 171 over Johnson CK
AT HWY 81 & 171 INTCHGE, Clackamas, Oregon
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: Hwy 81SB - Hwy 171
The Hwy 81SB - Hwy 171 bridge in Clackamas, Oregon carries Hwy 81SB - Hwy 171 over Johnson CK. It was built in 1968, making it 58 years old today. It was last reconstructed in 1991, extending its service life. The structure is built primarily of concrete continuous and spans 3 sections, stretching 45.7 meters (150 feet) end to end. Daily traffic averages 10,847 vehicles, placing it in the heavily-trafficked tier of Oregon bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 6/9, superstructure at 6/9, substructure at 6/9. The weakest component sits in fair condition. All reported major components score above the Poor range. Its NBI inventory load rating is 29.2 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How Hwy 81SB - Hwy 171 compares
Live comparison across Oregon.
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 How the historical reference is calculated.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
- 1968
- Last Reconstructed
- 1991
- Material
- Concrete Continuous
- Number of Spans
- 3
- Structure Length
- 45.7 m (150 ft)
- Deck Width
- 11.9 m (39 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 10,847 vehicles/day
- Structure Number
- 09670A01EC00551
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
- • The superstructure (beams and supports above the deck) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
- • The substructure (piers and abutments) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
How to read this record
This page shows what the last federal inspection recorded, not whether Hwy 81SB - Hwy 171 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 Hwy 81SB - Hwy 171 against other structures in Clackamas 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 Hwy 81SB - Hwy 171?
Hwy 81SB - Hwy 171 in Clackamas, Oregon has a deck rating of 6/9, superstructure rating of 6/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is Hwy 81SB - Hwy 171 inspected?
Hwy 81SB - Hwy 171'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 10,847 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. Hwy 81SB - Hwy 171 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 Hwy 81SB - Hwy 171?
Hwy 81SB - Hwy 171 has an NBI inventory load rating of 29.2 metric tons.
Who is responsible for maintaining Hwy 81SB - Hwy 171?
Hwy 81SB - Hwy 171 is owned and maintained by State Highway Agency.
How old is Hwy 81SB - Hwy 171 and does age affect safety?
Hwy 81SB - Hwy 171 was built in 1968, making it 58 years old and last reconstructed in 1991.
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.