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Sunnyside, WA

On September 16, 1902, residents voted 42 to one to incorporate as the town of Sunnyside. By state law, a town needed to have 300 citizens in order to legally incorporate. With 314 residents, Sunnyside was just eligible to legally vote for incorporation. The settlement was founded by Walter Granger in 1893. The name “Sunnyside” was coined by a merchant named W. H. Cline. Later, in the 1930s, refugees from the Dust Bowl also moved to Sunnyside. In 1948, Sunnyside became the first city in the State of Washington to adopt the Council-manager plan of government (see RCW 35A.13). Sunnyside was awarded the distinction of being an All-America City in 1979.

Quick Facts

  • City Established:1902
  • Population Size: 15,858
  • Fun Fact: Bonnie J. Dunbar, NASA astronaut; she graduated from Sunnyside High School in 1967.


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