Washington State Route 531
State highway in Snohomish County, Washington, US
State Route 531 (SR 531) is a short state highway in Snohomish County, Washington, United States. It runs from west to east along 172nd Street between Wenberg County Park on Lake Goodwin to a junction with SR 9 in southern Arlington, with an intermediate interchange with Interstate 5 (I-5) in Smokey Point. The highway is the primary access point for the Arlington Municipal Airport and the Smokey Point retail corridor.
SR 531 was created by the state legislature in 1991, using existing roads that were built in the early 20th century. Retail and housing development in the Smokey Point area triggered several expansion projects in the 1990s and 2000s to accommodate growing traffic volumes. The I-5 interchange was rebuilt and expanded between 2004 and 2010, including the addition of a loop ramp and a wider overpass. Its eastern terminus at SR 9 was converted into a roundabout in 2012.
Route description
SR 531 begins at the entrance to Wenberg County Park, a former state park located on Lake Goodwin. The highway travels north on a section of East Lake Goodwin Road, which continues around the south and west sides of the lake. At the north end of the lake, SR 531 turns east onto Lakewood Road, a rural two-lane highway that passes several suburban subdivisions.
The public source identifies “Washington State Route 531” as state highway in Snohomish County, Washington, US. This brief keeps that definition visible, then builds a research path around Washington, State and Route.
Why this record matters
A short description can identify a subject without explaining its stakes. For “Washington State Route 531”, the useful work is to connect “state highway in Snohomish County, Washington, US” to the records capable of establishing context and consequence.
The strongest evidence will usually combine a dated visual record with documents produced by the authority responsible for the place. The source revision retrieved here is dated Feb 21, 2026. The linked authority identifier is Q452653. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1991, 2004, 2010 and 2012.
Architectural summaries often privilege surviving fabric and can understate demolished phases, contested use or displaced communities. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “Washington State Route 531”, its source revision and the description used here.
- Expand the search: follow Washington State Route 531 primary sources, Washington State Route 531 archive and Washington research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Washington State Route 531”?
- Which authority defined the place, boundary or structure at the relevant date?
- Which earlier names or jurisdictions may reveal additional records?
Search terms from this dossier
This entry incorporates text from “Washington State Route 531” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.