Waterville is a town in Le Sueur County, Minnesota, United States. The population was 1,868 at the 2010 census. It is close to Sakatah Lake …Waterville is a town in Le Sueur County, Minnesota, United States. The population was 1,868 at the 2010 census. It is close to Sakatah Lake State Park on the Cannon River. Waterville has a yearly celebration called "Bullhead Days," and it is held in early June; the residents of the town get together for food, fun, a parade, a carnival, and fireworks.