Mo. Rev. Stat. § 249.390
When such report is filed, the question shall be submitted of whether the board of trustees shall have authority to issue bonds for the purpose of anticipating the revenues of said subdistrict for the cost of construction of said system of sewers, the total amount of said bonds not to exceed the estimated cost as shown in the report of the chief engineer. If a majority of such voters, voting on the question, shall vote in favor of authorizing the board of trustees to issue such bonds, the board of trustees shall have the power to issue and sell the same in the same manner as is provided in section 249.090 for the issuance and sale of other bonds of the district. Bonds issued under this section shall not run for a period of more than twenty years nor bear a higher rate of interest than six percent per annum.
§ 249.390, RSMo