Mo. Rev. Stat. § 256.300
The clean water commission is authorized to make reasonable assurance that demands for use will be made within a period of time to permit payment of costs allocated to water supply within the life of the project, and upon receipt of specific appropriations from the fund may enter into contract with the appropriate federal departments for purposes of discharging nonfederal responsibilities relating to municipal and industrial water supply storage as permitted by applicable federal legislation on water resource projects and, in so doing, shall consider the projected water needs of the area that can be served by the project and shall also consider the ability of future users to reimburse any investment of funds that may be made by this state.
§ 256.300, RSMo