The department of land and natural resources shall, within a reasonable time thereafter, determine whether the operation of the proposed district would be administratively practicable and feasible; provided that it shall not have the authority to determine in favor of the creation of the district unless at least a majority of the votes cast in the referendum shall have been cast in favor thereof. In making such determination and in determining the need for a proposed district, the department shall give due regard to the topography, composition of soils, distribution of erosion, prevailing land use practices within the proposed district, the probable expense of carrying on erosion control operations within the district and other relevant geographical, physical, economic, and social factors. If the department determines in favor of the creation of a district it shall make public the result of the election to elect directors. The three candidates who receive the largest number, respectively, of the votes cast in the election, shall be the elected directors for the district and the department shall appoint two directors to act with the three elected directors as the governing body of the district.