A municipal corporation may contract with any individual or an incorporated company for supplying water for fire purposes, or for cisterns, reservoirs, streets, squares, and other public places within its limits, or for the purpose of supplying the citizens of such municipal corporation with water for such time, and upon such terms as is agreed upon. Such contract shall not be executed or binding upon the municipal corporation until it has been ratified by a vote of the electors thereof, at a special or general election. The municipal corporation shall have the same power to protect such water supply and prevent the pollution thereof as though the water works were owned by such municipal corporation.