Washington State Route 171
State highway in Grant County, Washington, US
State Route 171 (SR 171, named Broadway Avenue) is a 3.79-mile (6.10 km) long state highway serving the city of Moses Lake in Grant County, located in the U.S. state of Washington. Broadway Avenue begins at an interchange with Interstate 90 (I-90) and travels northeast through Downtown Moses Lake concurrent to Interstate 90 Business and parallel to Parker Horn before ending at an intersection with SR 17. Broadway Avenue was previously part of Primary State Highway 18 (PSH 18) and U.S. Route 10 (US 10) until the 1964 highway renumbering. The highway also has an un-built extension from Moses Lake northeast to Odessa that was first legislated in 1955 as Secondary State Highway 7E (SSH 7E).
Route description
State Route 171 (SR 171) and Interstate 90 Business (I-90 Business) begin their 2.99-mile (4.81 km) long concurrency as Broadway Avenue at a diamond interchange with Interstate 90 (I-90) in Moses Lake. The street travels north over a branch of the Columbia Basin Railroad into Downtown Moses Lake and turns northeast to parallel the Parker Horn before the split between SR 171 and I-90 Business, which becomes Pioneer Way. The highway continues northeast to leave Downtown Moses Lake and end at an intersection with SR 17, which bypasses the city.
Every year the Washington State Department of Transportation (WSDOT) conducts a series of surveys on its highways in the state to measure traffic volume. This is expressed in terms of annual average daily traffic (AADT), which is a measure of traffic volume for any average day of the year. In 2011, WSDOT calculated that between 3,900 and 21,000 vehicles per day used the highway, mostly in the Yakima area.
The public source identifies “Washington State Route 171” as state highway in Grant 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 171”, the useful work is to connect “state highway in Grant County, Washington, US” to the records capable of establishing context and consequence.
Place names and jurisdictional language are key evidence: both can reveal earlier catalogue descriptions and overlooked record series. The source revision retrieved here is dated Dec 15, 2025. The linked authority identifier is Q835729. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1964, 1955 and 2011.
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 171”, its source revision and the description used here.
- Expand the search: follow Washington State Route 171 primary sources, Washington State Route 171 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 171”?
- 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 171” 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.