A CLASS action against the Murray-Darling Basin Authority will head to trial next month, after almost six years since being lodged.
The long-running class action will see claims of negligent water management, including the failure to consider the impacts of climate change, go up against the water authority.
The class action was brought forward by a group of nine Murray River irrigators who have claimed financial losses of $750 million.
It was claimed that the negligent actions saw 850,000 megalitres of water from Murray River dams being wasted rather than allocated to their properties.
Due to the draining of the Menindee Lakes from a flood in 2017, the water allocation was pushed downstream which the plaintiffs claim was unnecessary and in bad management.
At the start of the class action, the group also called for the Murray-Darling Basin Plan to be paused and undergo a review.
In addressing claims in 2024 in the class action, the defendant admitted that Menindee Lakes, comprised of four main lakes – Lake Wetherell, Pamamaroo, Menindee and Cawndilla, are very shallow with a large surface area.
The defendant in their defence claims state that the lakes “suffer from a high risk of evaporation in that; they are estimated on average to lose 426 GL a year to evaporation, and to lose up to 700 GL a year to evaporation when the lakes are full”.
They also state that “between October 2016 and January 2019: around 900 GL is estimated to have been lost from the Menindee Lakes through evaporation; and total system losses from the lakes, including seepage, is estimated to be over 1200 GL”.
There were also admissions that “where reserves in Menindee Lakes were low, added strain may be placed on the Barmah Choke if Lake Victoria is drawn down and there are low tributary inflows; and where there were limited tributary inflows, it would be difficult to meet large demands downstream of the Barmah Choke without access to water for release from the Menindee Lakes”.
The defendants also stated that “from around October 21, 2016, to around January 8, 2017, the releases directed from Menindee Lakes primarily comprised environmental water and that from around January 9, 2017, to around April 26, 2017, the releases from the Menindee Lakes primarily comprised operational releases to meet downstream Murray demands”.
