Washington Township is one of fifteen townships in Wayne County, Indiana, United States. As of the 2010 census, its population was 1,436 and it contained 626 housing units.[3]
According to the 2010 census, the township has a total area of 42.08 square miles (109.0 km2), of which 41.6 square miles (108 km2) (or 98.86%) is land and 0.48 square miles (1.2 km2) (or 1.14%) is water.[3] The streams of Brethren Run, Butlers Creek, Central Run, City Run, Common Run, Dry Branch, Franklin Creek, Greens Fork, Martindale Creek, Milton Drain, Shaker Run, Warm Run, Wilson Run and Woodclinch Brook run through this township.