Waynesville Township, DeWitt County, Illinois  Waynesville Township is one of thirteen townships in DeWitt County, Illinois, USA. As of the 2010 census, its population was 713 and it contained 318 housing units. According to the 2010 census, the township has a total area of , all land. The township contains these six cemeteries: Big Grove, Evergreen, Fairview, Halsey, Rock Creek and Union.