Mo. Rev. Stat. § 204.565
One or more political subdivisions of this state not within a common sewer district formed pursuant to sections 204.250 to 204.470 may be joined as an unincorporated subdistrict to such common sewer district, regardless of whether such political subdivision lies in the natural drainage area or basins of such district, in the following manner: The governing body of any such political subdivision, together with the trustees of the common sewer district, may petition the circuit court having jurisdiction over the major portion of the area to be joined to the common sewer district as the proposed subdistrict for extension of the boundaries of the common sewer district to include as a subdistrict the area within the political subdivision described in the petition. The petition shall also set forth a name for the proposed subdistrict, shall state the purposes for which such subdistrict of the common sewer district is to be created, shall set forth the boundaries of the proposed subdistrict, and shall have a map of the proposed subdistrict attached thereto.
§ 204.565, RSMo
Effective 2/18/1992