(1) If the long - term average sustainable diversion limit for the water resources of a water resource plan area (or for a particular part of those water resources) is reduced, the Basin Plan must specify:
(a) the amount of the reduction; and
(b) the amount of so much (if any) of the reduction as is attributable to changes in Commonwealth Government policy (the Commonwealth Government policy component of the reduction); and
(c) the amount of so much (if any) of the reduction as is attributable to improvements in knowledge about the environmentally sustainable level of take for the water resources of the water resource plan area (the new knowledge component of the reduction); and
(d) the amount of so much (if any) of the reduction as is the Commonwealth's share of the reduction (worked out under subsection (2)).
Each of the amounts referred to in paragraphs (a), (b), (c) and (d) is to be expressed as a quantity of water per year.
(1AA) For the purposes of subsection (1), the Basin Plan may specify the amounts in relation to:
(a) cumulative reductions (which may include a reduction that is taken to have occurred under subsection 78(3) from the amount specified for the purposes of subsection 78(2)); or
(b) reductions resulting from changes to the SDL from time to time.
(1A) In working out the amount of the Commonwealth Government policy component or the new knowledge component, any reduction that is a result of matters referred to in clause 48 of the National Water Initiative is to be disregarded.
Note: Clause 48 of the National Water Initiative is set out in Part 1 of Schedule 3A.
(2) The Commonwealth's share of the reduction is to be worked out as follows:
(a) the Commonwealth's share of the reduction includes the Commonwealth Government policy component of the reduction (if any); and
(b) if the Basin State in which the water resource plan area is located is not a State to which section 74A applies, and the reduction is one that takes effect on or after 1 January 2015--the Commonwealth's share of the reduction also includes so much of the new knowledge component (if any) as is worked out under subsection (3); and
(c) if the Basin State in which the water resource plan area is located is a State to which section 74A applies--the Commonwealth's share of the reduction also includes so much of the new knowledge component (if any) as is worked out under subsection (3A).
(3) The amount to be included in the Commonwealth's share of the reduction under paragraph (2)(b) is to be worked out on the basis that, for reductions in the long - term average sustainable diversion limit for the water resources, or that part of the water resources, of the water resource plan area in any 10 year period, the Commonwealth's share of the reductions:
(a) does not include so much of new knowledge components of those reductions as does not exceed (in aggregate) 3% of the relevant diversion limit; and
(b) includes two - thirds of so much of the new knowledge components of those reductions as:
(i) exceeds (in aggregate) 3% of the relevant diversion limit; and
(i) does not exceed (in aggregate) 6% of the relevant diversion limit; and
(c) includes 50% of so much of the new knowledge components of those reductions as exceed (in aggregate) 6% of the relevant diversion limit.
(3A) The amount to be included in the Commonwealth's share of the reduction under paragraph (2)(c) is to be worked out on the basis that, for reductions in the long - term average sustainable diversion limit for the water resources, or that part of the water resources, of the water resource plan area in any 10 year period, the Commonwealth's share of the reductions:
(a) does not include so much of new knowledge components of those reductions as does not exceed (in aggregate) 3% of the relevant diversion limit; and
(b) includes all of so much of the new knowledge components of those reductions as exceeds (in aggregate) 3% of the relevant diversion limit.
(4) For the purposes of applying subsection (3) or (3A) for a reduction in the long - term average sustainable diversion limit for the water resources, or part of the water resources, of a water resource plan area, the relevant diversion limit is the earliest long - term average sustainable diversion limit for those water resources, or that part of those water resources, that applied:
(a) during the 10 years immediately preceding the reduction; and
(b) on or after:
(i) if the Basin State in which the water resource plan area is located is a State to which section 74A applies, and a transitional water resource plan or an interim water resource plan has effect for the area--the day on which that plan ceases to have effect; or
(ii) in any other case--1 January 2015.
Note: The surface water of the Googong Dam Area is to be treated as if it were located in the Australian Capital Territory (see section 63A).