358C.18  Additional territory.
  1.  The district may be enlarged and additional territory annexed to the district by either of the following methods:
  a.  By petitions signed by the owners of all the property to be annexed to the district. If a petition requesting annexation is presented to the trustees and approved by the trustees the change in the boundaries to include the additional area shall be certified by the clerk of the district to the county auditor in which the greater portion of the district is located and thereafter the district shall include the area thus annexed.
  b.  By a petition filed with the clerk of the district, signed by persons owning not less than fifty percent of the area to be annexed, but not signed by persons owning all the area requested to be annexed. On the filing of the petition, the trustees of the district shall fix a time and place for a hearing on the petition and give notice of the hearing, as provided in section 331.305, and by certified mail to the record owners of all persons owning land within the territory sought to be annexed, not less than ten days prior to the date of the hearing, if the address of the owners is known or can be ascertained by reasonable diligence by the trustees. At the hearing, any person owning property within the area proposed to be annexed or any person owning property or residing within the district may appear and be heard. If, after the hearing, the board of trustees determines that annexation of the additional area will be conducive to the public health, convenience, and welfare and will not be an undue burden on the district, the board of trustees may, by resolution, annex the additional area and fix the boundary which shall not include more than the area requested in the petition. A copy of the resolution shall be filed with the county auditor of the county in which the largest portion of the district is located and thereafter the area included by the resolution shall be a part of the district.
  2.  All property, from and after it is annexed to the district, shall be subject to all taxes and other burdens levied by the district, regardless of when the obligation for which the taxes or assessments are levied was incurred.
95 Acts, ch 200, §18