(a) The board may adjourn the hearing from one day to another and until all persons desiring to be heard are heard. The board immediately shall specifically describe all property it proposes to exclude on its own motion and shall hear first any protests and evidence against exclusions proposed on the board’s own motion.
(b) After considering all engineering data and other evidence presented to it, the board shall determine whether the facts disclose the affirmative of the propositions stated in Subdivision (1) or (2) or, if appropriate, in Subdivision (3) of § 49.306. If the affirmative exists, the board shall enter an order excluding all land or other property falling within the conditions defined by the respective subdivisions and shall redefine in the order the boundaries of the district to embrace all land not excluded. A copy of the order excluding land and redefining the boundaries of the district shall be filed in the deed records of the county or counties in which the district is situated.