For the purpose of owning, operating, constructing, and equipping a sewage disposal plant and sewerage system, including any storm sewer system, or improving or extending such existing system, as provided in section 14-365.01, or for the purpose stated in sections 14-365.01 to 14-365.05, any city of the metropolitan class is also authorized to issue and sell general obligation bonds of such city upon compliance with section 14-365.07. Such bonds shall not be sold or exchanged for less than the par value of such bonds and shall bear interest payable semiannually. The city council shall have the power to determine the denominations of such bonds, and the date, time, and manner of payment.