Official controls instituted by a board may include specific ordinances, resolutions, orders, regulations, or other such legal controls pertaining to other elements incorporated in a drainage plan, project, or area or establishing standards and procedures to be employed toward drainage management. Any such ordinances, resolutions, regulations, or controls shall embody the basic principle that any rural land which drains onto other rural land has a right to continue such drainage if:
(1) The land receiving the drainage remains rural in character;
(2) The land being drained is used in a reasonable manner;
(3) The drainage creates no unreasonable hardship or injury to the owner of the land receiving the drainage;
(4) The drainage is natural and occurs by means of a natural water course or established water course;
(5) The owner of the land being drained does not substantially alter on a permanent basis the course of flow, the amount of flow, or the time of flow from that which would occur; and
(6) No other feasible alternative drainage system is available that will produce less harm without substantially greater cost to the owner of the land being drained.
Such provisions do not necessarily apply within municipalities, but if a municipality drains water onto rural lands lying outside the boundaries of the municipality, the municipality is subject to the above provisions, if adopted by the board.