Augusta is a city in Butler County, Kansas, United States. As of the 2020 census, the population of the city was 9,256. It is located east of Wic…Augusta is a city in Butler County, Kansas, United States. As of the 2020 census, the population of the city was 9,256. It is located east of Wichita along U.S. Route 54 / 400 highway. The confluence of the Whitewater River and the Walnut River was originally inhabited by Osage people, who found the land ideal for hunting and fishing.