Wisconsin Rapids is a city in and the county seat of Wood County, Wisconsin, United States, along the Wisconsin River. The population …Wisconsin Rapids is a city in and the county seat of Wood County, Wisconsin, United States, along the Wisconsin River. The population was 18,877 at the 2020 census. It is a principal city of the Marshfield–Wisconsin Rapids micropolitan statistical area, which includes all of Wood County and had a population of 74,207 in 2020.