Iowa Code § 468.601
Upon the filing of any such application, the auditor shall forthwith fix a time and place for hearing thereon before the county board of supervisors, which hearing shall be not more than ninety days nor less than thirty days from the time of the filing of such application, and cause notice in writing to be served upon the owner of each tract of land across which any such levee, ditch, or drain is proposed to be located, as shown by the transfer books in the office of the county auditor, and also upon the person in actual occupancy of any such lands, of the pendency and prayer of such application and the time and place set for hearing on the same before the board of supervisors, which notice, as to residents of the county and railroad companies, shall be served not less than ten days before the time set for such hearing, in the manner that original notices are required to be served. Notice to a railroad company may be served upon any station agent.
Iowa Code § 468.601
89 Acts, ch 126, §2
Manner of service, R.C.P. 1.302 - 1.315