Wasioja is the native Sioux language name for the Zumbro River.

[3] According to the United States Census Bureau, the township has a total area of 36.1 square miles (93.5 km2), all land.

As of the census[1] of 2000, there were 963 people, 326 households, and 280 families residing in the township.

There were 326 households, out of which 40.2% had children under the age of 18 living with them, 78.5% were married couples living together, 4.9% had a female householder with no husband present, and 14.1% were non-families.

12.3% of all households were made up of individuals, and 4.0% had someone living alone who was 65 years of age or older.