If any levee or drainage district or improvement established either by legal proceedings or by private parties shall desire to include in the activities of such district soil conservation or flood control projects, the board upon petition, as for the establishment of an original levee or drainage district, shall establish a new district covering and including such old district and improvement together with any additional lands deemed necessary. All outstanding indebtedness of the old levee or drainage district shall be assessed only against the lands included therein.
C95, §161F.4