Watopa Township was organized in 1858, and named for the Dakota-language word meaning "paddle a canoe".

As of the census[1] of 2000, there were 265 people, 95 households, and 72 families residing in the township.

There were 95 households, out of which 35.8% had children under the age of 18 living with them, 70.5% were married couples living together, 3.2% had a female householder with no husband present, and 23.2% were non-families.

18.9% of all households were made up of individuals, and 5.3% had someone living alone who was 65 years of age or older.

About 4.8% of families and 2.6% of the population were below the poverty line, including none of those under the age of eighteen and 8.7% of those 65 or over.