The securities authorized to be issued hereunder shall be serial in form and the entire issue of said conservation and development fund bonds so serially to be issued shall begin to mature within five years after the issuance thereof and a like amount as near as may be of principal and interest shall fall due and mature annually thereafter as in the case of other conservancy bonds, save that the life of the bonds authorized under the terms of this act N.M. Stat. Ann. § 73-16-30 to 73-16-40 shall be so adjusted serially that all of the principal and interest thereof shall fall due and be payable within the life of the original construction fund bonds.