The board shall file with the secretary a copy of the report and the plans and specifications, and a notice of the filing of the report stating all the following:
(a) The purpose of the report.
(b) Where the report may be inspected by any person interested.
(c) The time within which protests against the adoption of the report and the levying of any assesment thereunder may be filed.
(d) The time and place when a hearing on any protests will be had.