It shall be the mandatory duty of any reorganized common sewer district issuing any general or special revenue bonds under sections 204.600 to 204.640 to:
From time to time, the rates shall be revised to meet fully the requirements of sections 204.600 to 204.640. As long as any bond issued or the interest thereon shall remain outstanding and unpaid, rates and charges sufficient to meet the requirements of this section shall be maintained and collected by the reorganized common sewer district that issued the bonds.
§ 204.630, RSMo