1. The drainage enhancements shall be set forth in a statement signed by the department, which together with the map of the district shall be filed and notice of a hearing thereon at which grievances will be heard shall be given. At such hearing objectors shall be heard as to the property lines shown on the maps and the drainage enhancements shown on the statement thereof.

2. After the close of the hearing the department may amend both maps and statement, adopt the statement in final form and shall file such amended maps and final statement and give notice of such filing. Thereupon such amended maps and final statement shall be recorded when and as provided in section 15-1927.