No water pipe of the city water system shall be connected with any pump, well, pipe, tank or any device that is connected with any other source of water supply; and when such are found, the city shall notify the owner or occupant to disconnect the same. If the disconnection is not made immediately, the city water service shall be discontinued. Before any new connections to the city system are permitted, the city shall ascertain that no cross-connections will exist when the new connection is made. When a building is connected to “city water,” any private water supply may be used only for such purposes as the city may allow.
(1998 Code, § 3.20, Subd. 5)