"'distribution system' means pipes, and related fittings, that are not a service connection, that are not owned by, vested in or controlled by a water services authority, an authorised provider of water services, or a person providing water services jointly with or on behalf of a water services authority or an authorised provider of water services, and that are used, or to be used as the case may be, to convey water into or through one or more premises (including any related internal or external taps), extending, in the case of water used in manufacturing or food or drinks production undertaking, to include the point where water is used in the undertaking;".