Any city of the metropolitan class that has adopted a home rule charter may exercise any powers granted in sections 14-1201 to 14-1251 in the method provided by this section or by such other method, in whole or in part, as may from time to time be provided in whole or in part by such home rule charter. The powers conferred by such sections shall be exercised without any restriction or limitation under the home rule charter or laws of the state except the provisions of the Constitution of Nebraska, and are supplementary and additional to powers which have been or may hereafter be conferred upon the city by the laws of the state or such home rule charter. All powers granted or provided to be conferred upon bridge commissions authorized by such sections are likewise granted to and conferred upon and may be exercised by the city council and such city council may delegate to any bridge commission created for such city under such sections, in the discretion of such city council, any or all of the powers, privileges, and rights of approval and restraint conferred upon it by such sections.