Subject to the provisions of Kan. Stat. Ann. § 19-270, the governing body of any main, lateral or joint sewer district, by resolution, may enlarge the boundaries of the district upon the presentation of a petition approved by the district engineer. The petition shall be signed by the owners of at least 51% of the area sought to be added to the district. The petition shall state the requirements listed in subsection (b) of Kan. Stat. Ann. § 19-27a03, and amendments thereto. The resolution shall provide for the levying of taxes or special assessments, as may be appropriate, upon the property in the added area, the same as are being levied upon the property in the district, to pay the principal and interest on outstanding bonds issued for the payment of costs of improvements in the district. The resolution also shall provide for an additional special assessment upon the property in the added area to pay a proportionate share of all amounts previously paid by the district upon any bonds issued for such purposes. No area may be added to the district except where the sewage therefrom flows by gravity into the mains of the district unless the governing body, acting upon the recommendation of the chief engineer, determines that pumping is in the best interest of the area to be added. The additional levies shall be made over a period of years, as determined by the governing body, and the proceeds therefrom shall be credited to the bond and interest fund of the district.