Washington Township, Carroll County, Illinois  Washington Township is one of twelve townships in Carroll County, Illinois, USA. Home of the fRam. As of the 2010 census, its population was 356 and it contained 198 housing units. According to the 2010 census, the township has a total area of , of which (or 89.05%) is land and (or 10.95%) is water. (This list is based on USGS data and may include former settlements.) The township contains Mosquito Hill Cemetery which is also known as St. Peter's Evangelical Lutheran Cemetery. The cemetery is the site of the former St. Matthew's Evangelical Lutheran Church.