Before final action thereon the board shall conduct a public hearing on the plan after ten days published notice of hearing is given pursuant to RCW 36.32.120(7). The notice must set out the full official title of the proposed resolution adopting the plan and a statement describing the general intent and purpose of the plan. The notice shall also include the day, hour and place of hearing and must be given by publication in the newspaper in which legal notices of the county are printed. Ten days prior to the hearing, three copies of the sewerage and/or water general plan shall be filed with the clerk of the board. The copies shall be open to public inspection.