A senior Murray Darling Basin Authority executive says the body is "acutely aware" of the effects of record intervalley trades, out of the Goulburn River.
MDBA River Murray Operations director Jacqui Hickey said since 2004, there had been a steady increase in the amount of trade out of the Goulburn River.
She was speaking at a Shepparton Southern Murray-Darling Basin seasonal outlook forum.
"The last two years, the Goulburn has been the only IVT account that's been available to us," Ms Hickey said.
The MDBA had not been able to call on the Murrumbidgee River, as all the water from the Murray River had been traded up into it.
"In the last two years, there have been a lot of buyers in the Murrumbidgee, who have bought Murray water and traded it back up," Ms Hickey said.
"To fill state water orders, this year and the year before, we had to call on water out of the Goulburn.
"We do aim to draw on the IVT accounts - if we don't, it will put pressure on the Murray resource."
She said the MDBA was aware Victoria's Water Minister Lisa Neville had asked it not to draw as much water out of the Goulburn, especially in summer.
"It has been causing some damage to the banks in the banks of the lower Goulburn," Ms Hickey said.
"We are very acutely aware of that."
Ms Hickey said the MDBA had worked very closely with catchment management authorities, Goulburn-Murray Water and the states to "do everything we could" to minimise damage from the deliveries.
"But we had to get a certain volume through," she said.
"Now the Murrumbidgee IVT is available, and the Victorian government is making some interim changes to the trade, we do have some more options.
"We are looking at a suite of options that ensure people can get their water, but also to reduces running the Goulburn River high during summer."
Ms Hickey said during the peak summer delivery time, there wasn't enough channel capacity to meet South Australia's commitments, as well as other requirements along the Murray River.
"We have to transfer in winter and spring, to Lake Victoria, and that helps us meet SA's commitments, and allows us to meet everything else, through the existing channels."
"Sometimes we need to go over bank, and we schedule those (flows) during winter and spring because its better for the environment and losses are lower than if we had to do that over the summer."
Yea beef producer Jan Beer said she had no idea the Goulburn River was supplying most of the intervalley trade.
"It also shows how the Victorian minister is having to impose restrictions, to stop, or attempt to stop, the destruction caused by the MDBA, the very body charged with the responsibility of 'optimising' environmental outcomes," Ms Beer said.
Taking the Murrumbidgee River out of the IVT equation for two years meant the Goulburn River had felt the full impact.
"This clearly shows their Basin Plan and government water policies are simply not working and resulting in severe environmental degradation."
Ms Beer said with the Darling and Murrumbidgee no longer contributing to South Australian flows, it was absolutely unachievable and impossible to send 80,000 gigalitres of water to the border.
"So why persist with the 450GL?"
Andrew Miller
I'm a general reporter with Stock & Land, with a special interest in irrigation issues. I completed my cadetship, with the Age, in 1980. Over my career, I've worked for ABC radio news (Mt Isa, Qld) and at provincial and suburban newspapers.
I'm a general reporter with Stock & Land, with a special interest in irrigation issues. I completed my cadetship, with the Age, in 1980. Over my career, I've worked for ABC radio news (Mt Isa, Qld) and at provincial and suburban newspapers.
