South Otter Township, Macoupin County, IllinoisSouth Otter Township is located in Macoupin County, Illinois, United States. As of the 2010 census, its population was 465 and it contained 204 housing units.GeographyAccording to the 2010 census, the township has a total area of, of which is land and is water.Adjacent townships North Otter Township Girard Township Nilwood Township Shaws Point Township Carlinville Township Bird Township South Palmyra Township North Palmyra Township