 According to the United States Census Bureau , the city encompasses a total area of 3 @.@ 5 square miles ( 9 @.@ 06 km2 ) , including 0 @.@ 07 square miles ( 0 @.@ 18 km2 ) of water , accounting for two percent of the overall area . The area expanded in April 2010 , when 0 @.@ 56 square miles ( 1 @.@ 5 km2 ) of land formerly within the city of Okanogan was accumulated . Omak is the fourth largest settlement in Okanogan County by area after Nespelem Community ( 23 sq mi ; 60 km2 ) , North Omak ( 11 @.@ 2 sq mi ; 29 km2 ) and Disautel ( 3 @.@ 80 sq mi ; 9 @.@ 8 km2 ) . Omak covers 0 @.@ 07 percent of the county 's total area . Its 4 @.@ 83 @-@ square @-@ mile ( 12 @.@ 5 km2 ) urban cluster , the Greater Omak Area , includes the city of Okanogan and the CDP of North Omak . The surrounding metropolitan region comprises a total area of 1 @,@ 037 square miles ( 2 @,@ 690 km2 ) , although it has not officially been designated as a statistical area . 
