The summons may be served by publication as to any defendants who cannot be personally served, as provided by law. The service of such summons upon the station agent of any railroad, interurban or other company in any county in which the right of way of such company will be affected by such drainage will be sufficient notice to such railroad or other company and in case there be no agent of any such company in such county such company shall be notified in the same manner as nonresident landowners.