Owasa is a city in Hardin County, Iowa, United States. The population was 34 at the time of the 2020 census. Owasa was platted in 1883 or 188…Owasa is a city in Hardin County, Iowa, United States. The population was 34 at the time of the 2020 census. Owasa was platted in 1883 or 1884. The name is derived from the Fox language, meaning "bear".