The governing authorities of any county or city of this state which has acquired or may hereafter acquire any combined railroad and highway bridge over the Mississippi River, as authorized by Sections 65-23-1 through 65-23-21 or Sections 65-25-1 through 65-25-41, and which has discharged the bridge revenue bonds which were issued for the purpose of financing the cost of such acquisition and has freed the bridge as to the vehicular portion thereof from tolls may, by appropriate resolution, create a commission of five members to manage the affairs of said bridge, said appointees to be qualified electors of such governing body of high character, integrity, and business acumen; and, if such governing body has already created a commission under the provisions of Sections 65-25-43 through 65-25-47, then in lieu of creating another commission, the governing authorities of such county or city may, by order entered upon the minutes of such authority, continue the present commission in effect.