Recovering 450GL cuts consumptive water pool by 10pc in NSW, Vic & SA

Along with stripping agriculture communities of water and driving up its price, the additional water would do little to solve the environmental issues faced by the Murray-Darling Basin, such as the carp invasion, cold water pollution and poor water quality.

The NSW Irrigator's Council report found recovering the NSW share (212GL) of the additional 450GL is the equivalent of recovering 9.9 per cent of total consumptive water in the NSW southern valleys.

Victoria's share (197GL) represents 10.5 per cent of total consumptive water in the state's southern basin valleys and SA's (38GL) would cut 10.8pc of the total remaining consumptive water in the SA Murray.

"Recovery of the additional 450GL represents a very large proportion of the remaining water in the consumptive pool in the southern connected systems," the report stated.

The Albanese government made delivering the basin plan in full, including the 450GL, a key election promise.

NSWIC acting chief executive Christine Freak said more water wouldn't address the largest ecological needs of the basin and if the government wanted environmental outcomes, it had to look at complementary measures.

"Water has become so politicised that when you mention complementary measures, it's viewed as sub-optimal to buybacks or a way to get out of them," Ms Freak said.

"But the problems we have can't be fixed with more water."

She said the focus should shift to directly targeting key degradation drivers such as carp, habitat degradation, barriers to fish passage, fish screens on pumps, and forming partnerships with landholders for environmental water delivery.

Unlike the rest of the basin plan, the 450GL was never modelled and added at the last minute to secure South Australia's support.

Because of this, Ms Freak said the target was set up to fail from the very beginning, while the Productive Commission stated the policy was becoming increasingly detached from achieving environmental outcomes.

"It is essentially a political deal struck a decade ago, rather than a scientifically-modelled policy decision," Ms Freak said.

"This is a political construct that's being placed ahead of critical environmental needs and it will have severe socio-economical consequences. It doesn't make any sense to push ahead."

Federal Water Minister Tanya Plibersek reiterated the government's commitment to the 450GL target last week, as she announced an extension to the basin plan's mid-2024 deadline.

"From my perspective and the law, the 450 gigalitres is part of the Murray-Darling Basin Plan and there's no conversation about that," Ms Plibersek said.