South dakota constitution
Article IX: local government
Section 1

The Legislature shall have plenary powers to organize and classify units of local government, except that any proposed change in county boundaries shall be submitted to the voters of each affected county at an election and be approved by a majority of those voting thereon in each county. No township heretofore organized may be abolished unless the question is submitted to the voters of the township and approved by a majority of those voting thereon in each township.