The Gillard government has pledged $1.77 billion for water infrastructure to pump an extra 450 billion litres into the ailing Murray Darling basin to boost the health of the river system.
The Prime Minister, Julia Gillard, and Water Minister, Tony Burke, will be joined by the South Australian Premier, Jay Weatherill, to release the plan this morning in Goolwa, south of Adelaide.
The money, which will be spent from 2014, will go towards improving farm infrastructure so that irrigation water can be used more efficiently, saving the extra billions of litres for the environment, particularly wetlands and the Lower Lakes in South Australia.
It would "help ensure the system never again goes into a period of drought lacking the resilience it needs to survive", a statement released by the Prime Minister this morning said.
Today's announcement will take to 3200 billion litres the total amount of water returned to the environment under the Murray Darling basin plan. Recent modelling by the independent Murray-Darling Basin Authority found that an extra 450 billion litres would bring considerable environmental benefits.
The water recovery spending would "achieve greater environmental outcomes" but "minimise the impact on communities", the statement said.
Much of the water to be returned to the environment will be found through buybacks of irrigators' water rights. But irrigators say this will destroy rural communities, particularly in southern NSW and northern Victoria.
Conservationists and the South Australian government, meanwhile, have been demanding that much more water be returned to the environment to boost the health of wetlands and other sites that depend on natural flooding and water flows.
Mr Weatherill has threatened to go the High Court unless more water than the planned 2750 billion litres is returned the environment. But NSW and Victoria strongly oppose raising the figure.
Much of the water recovery money will be used to make irrigation more efficient on farms, so that food and other produce can be grown with less water. This can include levelling ground to reduce runoff, constructing pipes, lining and sealing channels and putting covers on dams to stop evaporation.
Some $200 million of the new money will be used to remove so-called "constraints" that prevent more water being flushed through the system, the statement said. These include low-lying bridges and undersized dam outlets the limit the volume of water that can flow through systems and the environmental uses to which it can be put.
Ms Gillard's statement said the new money would be found "from within existing resources and from funds set aside in the recent Mid-Year Economic and Fiscal Outlook". It would be "secured through a special account and advance appropriation of future funds to ensure its availability through to 2024".
The Coalition spokesman for water and regional development, Barnaby Joyce, questioned where the money would come from.
"[Mr Burke is] saying in the future, somebody else will borrow some money and do something wonderful for you, and I want you to thank me for it," he told ABC radio.
"They're making promises for things that are going to happen out to 2024. I mean, they'll be lucky to be there next year, let alone in 2024. So, what does this statement actually mean?"
Legislation would be introduced into federal Parliament by the end of the year.
with Dan Harrison