15(1)No rateable value shall be attributable to any new water undertaking until the year (in this paragraph referred to as “the valuation year”) second succeeding that in which it commences to supply water to consumers, and accordingly for the purposes of this paragraph paragraph 5 above shall apply as if for the reference to the year 1967-68 there were substituted a reference to the valuation year and for the references to the year 1965-66 there were substituted references to the year in which the undertaking so commences to supply water.S
(2)This paragraph applies only to new water undertakings and accordingly does not apply to a part of an undertaking which consists in an addition to an existing water undertaking.