Mo. Rev. Stat. § 236.020: Owner of land on one side of stream may erect dam.

Any person or corporation chartered and organized to construct, operate and maintain mills, electric power and light works, or other machinery, being the owner, in fee simple, of the land on one side of such watercourse, including a part of the bed of the stream, at a point where it is proposed to erect a dam, may, nevertheless, erect such dam by proceeding as herein provided.