Idaho Code § 42-2919
If the commissioners shall find after the investigation referred to that the cost, expenses and damages are more than equal to the increased value which will accrue to the lands within the district, they shall so report and the proceedings shall be dismissed. But if the commissioners shall report that the whole cost of the work including preliminary surveys and expenses, legal assistance and court costs will be less than the increase in value to accrue therefrom, they shall so report to the court, and the court shall then make and enter an order fixing a time and place when and where all persons interested may appear and contest the confirmation thereof, and the clerk of the court shall cause notices of the time and place of said hearing to be given to all parties interested by the publication of a notice thereof for at least three successive weeks prior to the date set for such hearing in one or more newspapers published in said county or counties which notice shall contain a description of all land affected and the amount of the assessments and damages awarded in said report and by personally serving or sending by registered mail a copy of said notice to each landowner at his post-office address in so far as the same can be ascertained, and if not known, then to their last known post-office address, at least twenty days before the date appointed for said hearing, but failure to receive such notice shall not invalidate any assessment.
Idaho Code § 42-2919