All reports, maps, plats, profiles, field notes, and other documents pertaining to said matters, including all schedules, and memoranda relating to assessment of damages and benefits, shall belong to the district to which they relate, remain on file in the office of the county auditor, and be matters of permanent record of drainage proceedings.
Iowa Code § 468.173
89 Acts, ch 126, §2
Referred to in §468.27, 468.298