NW SAMMAMISH ROAD
Carrying NW SAMMAMISH ROAD over TRIBUTARY 170
0.5 M WEST OF SR-900, King, Washington
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: NW SAMMAMISH ROAD
The NW SAMMAMISH ROAD bridge in King, Washington carries NW SAMMAMISH ROAD over TRIBUTARY 170. It was built in 2008, making it 18 years old today. The structure is built primarily of concrete and spans 1 section, stretching 7.9 meters (26 feet) end to end. Daily traffic averages 13,500 vehicles, placing it in the heavily-trafficked tier of Washington bridges. It is owned and maintained by City/Municipal Highway Agency.
The latest FHWA inspection records show culvert at 8/9. The weakest component sits in good condition. No reported major component scores in the Poor range under the current federal condition thresholds. Its NBI inventory load rating is 80.7 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How NW SAMMAMISH ROAD compares
Live comparison across Washington.
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 How the historical reference is calculated.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
- 2008
- Material
- Concrete
- Number of Spans
- 1
- Structure Length
- 7.9 m (26 ft)
- Deck Width
- 18.9 m (62 ft)
- Owner
- City/Municipal Highway Agency
- Avg Daily Traffic
- 13,500 vehicles/day
- Structure Number
- 088029000000000
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 NW SAMMAMISH 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 NW SAMMAMISH ROAD against other structures in King and across Washington. Washington 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 NW SAMMAMISH ROAD?
NW SAMMAMISH ROAD in King, Washington on the FHWA's 0–9 scale.
How often is NW SAMMAMISH ROAD inspected?
NW SAMMAMISH 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 13,500 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. NW SAMMAMISH ROAD 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 NW SAMMAMISH ROAD?
NW SAMMAMISH ROAD has an NBI inventory load rating of 80.7 metric tons.
Who is responsible for maintaining NW SAMMAMISH ROAD?
NW SAMMAMISH ROAD is owned and maintained by City/Municipal Highway Agency.
How old is NW SAMMAMISH ROAD and does age affect safety?
NW SAMMAMISH ROAD was built in 2008, making it 18 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.