A plan to conserve water for the recovery of Australia's biggest river system has come under fire after a report revealed it had fallen short of major targets.
The Murray Darling Basin Authority report on Thursday said there had been a 265-gigalitre annual shortfall in water to be kept from commercial use - the equivalent of 106,000 standard Olympic-sized swimming pools.
The commonwealth target set in 2017 was to retain 605 gigalitres of water annually from the basin, which spans more than one million square kilometres across five states and territories.
The national plan was to spend $1.4 billion on 39 pumps, pipes and other water infrastructure projects.
Only 13 of the projects had been completed and $733 million spent to date, the report stated.
An earlier assessment in June revealed 14 projects wouldn't be completed before the December 31 deadline, with a further three struck out.
Among those not to have been completed include the Nyah Floodplain Management Project, located 30km north of Swan Hill, Victoria.
It's home to 300-year-old red gums and the threatened regent parrot, an area conservationists warn could be deprived of river flow spilling into banks.
Another was the Living Murray Koondrook-Perricoota Floodplain Management Project, a plan to restore up to 33,750 hectares of river red gum forests and wetlands along the Murray River.
Murray Darling Conservation Alliance spokesman Chris Gambian said there was an urgent need to make up for the shortfall and keep the promise made to bring the system back to good health.
“This has been an expensive, harebrained scheme that has failed nature and communities alike," he said in a statement.
Federal Environment Minister Murray Watt said the commonwealth had not ruled out making up for the shortfall in buybacks.
"We're obviously disappointed that that's occurred, especially when we passed legislation in our first term giving the states more time to deliver those projects than what they initially had had," he told ABC.
"If we fail to meet the targets that are set under the basin plan, it's not just a sort of a mathematical exercise, it actually says that we're not doing what's needed to preserve the health of the basin system long-term."
The Murray-Darling Basin Plan determines how much water can be taken from the system while also supporting ecosystems.
The authority's report on Thursday was a draft determination of the Sustainable Diversion Limit Adjustment Mechanism.
It was designed under the basin plan by the former coalition government in 2017 to keep more water available for communities and irrigation.
It aimed to limit the need for further voluntary water buybacks, in exchange for basin states NSW, Victoria and South Australia to deliver projects that achieved similar environmental outcomes.
The authority is inviting the public for consultation in October before making a final decision on the proposed allocation of environmental water flows at year's end.
