Washington State Route 221
|Auxiliary route of SR 22|
|Defined by RCW|
|Maintained by WSDOT|
|Length:||25.95 mi (41.76 km)|
|Existed:||ca. 1926 – present|
|North end:||SR 22 at Prosser|
|South end:||SR 14 at Paterson|
State Route 221 (SR 221) is a 25.95-mile (41.76 km) long state highway located entirely within Benton County, Washington, United States. The highway serves to connect the unincorporated community of Paterson to the county seat Prosser. The highway has existed since at least 1926 as Primary State Highway 8E until the 1964 renumbering of Washington state highways.
Washington State Route 221 (SR 221) starts at an intersection with SR 14 in the unincorporated community of Paterson. After leaving Paterson the highway travels north through rural farm land as a two-lane highway. A few minor roads are intersected before the roadway turns to the west after about 17 mi (27 km), before turning back to the north. After the highway resumes its northerly course it climbs into the Horse Heaven Hills, gaining a passing lane through the uphill segments, before finally terminating at SR 22 in south Prosser.
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 average annual daily traffic (AADT), which is a measure of traffic volume for any average day of the year. In 2009, WSDOT calculated that as few as 2,000 cars traveled through the central part of the highway, and as many as 2,500 cars at the interchange with SR 22.
The roadway on its current alignment has existed since at least 1926, however there are records of a road between Paterson and Prosser since 1906. The highway was designated Secondary State Highway 8E (SSH 8E) since at least 1937, but the route number was changed during the 1964 state highway renumbering.
High winds have forced the closure of SR 221 in 2003, 2004, and 2005 due to large amounts of dust being blown around, causing visibility to drop to almost zero through the Horse Heaven Hills.
On September 13, 2007, on a recently repaved section of SR 221, an SSC Ultimate Aero TT broke the Guinness World Record for the World's Fastest Production Car after reaching an averaged top speed of 256.18 miles per hour (412.28 km/h).
|0.00||0.00||SR 14 – Roosevelt, Plymouth||At-grade intersection, southern terminus|
|25.95||41.76||SR 22 – Prosser||At-grade intersection, northern terminus|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi
- "State Highway Log Planning Report 2009 SR 2 to SR 971" (PDF). Washington State Department of Transportation (WSDOT). p. 1237. Retrieved 25 October 2010.
- The Road Atlas (Map). 1 in ≈ 20 mi. Cartography by Rand McNally. Rand McNally. 2009. p. 109. § K14 - L14. ISBN 978-0-528-94219-8.
- "2009 Annual Traffic Report" (PDF). WSDOT. p. 161. Retrieved 26 October 2010.
- Horse Haven Quadrangle (Map). Cartography by Brokaw, S. E. Automobile Club of Washington. 1926. Retrieved 25 October 2010.
- Blalock Island (Map). United States Geological Survey (USGS). 1906. Retrieved 25 October 2010.
- Prosser (Map). USGS. 1915. Retrieved 25 October 2010.
- Map of Benton County (Map). Washington State Department of Highways. 1937. Retrieved 25 October 2010.
- Prahl, C.G. (December 1, 1965). "Identification of State Highways" (PDF). Washington State Highway Commission - Department of Highways. Retrieved 25 October 2010.
- Taylor, John (November 19, 2003). "11/19/03 Around the Valley". Yakima Herald-Republic (The Seattle Times Company). p. B1. Retrieved 25 October 2010. (subscription required)
- "Storm sweeps state with wind, lightning". Ellensburg Daily Record (Pioneers Newspapers Inc). April 28, 2004. p. A8. Retrieved 25 October 2010.
- Muir, Patrick D. (March 17, 2005). "It was a real dust-up in Lower Valley". Yakima Herald-Republic (The Seattle Times Company). Retrieved 25 October 2010. (subscription required)
- "SSC Ultimate Aero Breaks Production Car World Speed Record" (Press release). West Richland, Washington: SSC North America. September 13, 2007. Retrieved February 22, 2015.