Whenever the county commission deems it necessary to provide for the construction of sewers as provided for in sections 249.430 to 249.660, it shall designate the county highway engineer or other qualified engineer as sewer engineer. The sewer engineer shall advise the county commission with reference to proper boundaries of any sewer districts to be established and shall also superintend the construction of the sewers and the maintenance thereof and the apportionment of the cost thereof as provided by law. The county commission shall also request the county clerk to appoint or designate a deputy county clerk to keep the special records which will, or shall be required for the proceedings for the construction and maintenance of sewer districts or divisions.