Iowa Code § 468.64: Presumption — jurisdiction.

Such connecting ditch or drain which a person shall cause to be constructed shall be presumed conducive to the public health, welfare, convenience, and utility the same as if it had been so constructed as a part of the original improvement of said district. When such subdistrict has been established and constructed it shall become and be a part of the improvement of such drainage district as a whole and be under the control and supervision of the board to the same extent and in every way as if it had been a part of the original improvement of such district.