Mo. Rev. Stat. § 70.240
The parties to such contract or cooperative action or any of them, or any joint board or commission formed pursuant to section 70.260 for the purpose of providing water or sewer services, may acquire, by gift or purchase, or by the power of eminent domain exercised by one or more of the parties thereto in the same manner as now or hereafter provided for corporations created under the law of this state for public use, chapter 523 and amendments thereto, or any joint board or commission formed pursuant to section 70.260 for the purpose of providing water or sewer services, the lands necessary or useful for the joint use of the parties for the purposes provided in section 70.220 or section 70.260, either within or without the corporate or territorial limits of one or more of the contracting parties, and shall have the power to hold or acquire said lands as tenants in common with the parties to such contract or in the name of any joint board or commission formed pursuant to section 70.260; provided however, that in no event shall any joint board or commission formed pursuant to section 70.260 for the purpose of providing water or sewer services exercise the power of eminent domain within the corporate or territorial limits of one of the contracting parties without such party's consent.
§ 70.240, RSMo