Clear lake is bordered on the southwest by the Mississippi River.

As of the census[1] of 2000, there were 1,630 people, 574 households, and 478 families residing in the township.

There were 821 housing units at an average density of 24.4 per square mile (9.4/km2).

13.8% of all households were made up of individuals, and 4.4% had someone living alone who was 65 years of age or older.

None of the families and 0.5% of the population were living below the poverty line, including no under eighteens and 4.0% of those over 64.