 The town began to develop after the completion of the Okanogan Irrigation Project, which was designed to facilitate farming. At this time, many farmers came to Omak looking for homes. Fruits including apples, berries, peaches, plums and watermelons were cultivated after 1910. Omak served as a census-designated place (CDP) in 1910, and incorporated as a city on February 11, 1911. Omak and Okanogan have shared a rivalry in high school sports. During the Great Depression of 1933, several residents of Omak were forced to work in nearby communities. As a result, the United States Bureau of Reclamation promoted work which was available as part of an improvement project at Grand Coulee Dam in nearby Coulee Dam, which employed approximately 5,000 people between 1933 and 1951 when the megaproject ended. By 1950, the city was home to various buildings and structures including the St. Mary Mission church, which satisfied residential needs.
