Nationals want to cork Menindee Lakes’ water release

Nationals deputy leader Perin Davey is calling for reforms to the Murray-Darling Basin agreement amid warnings additional flows into South Australia could speed up the depletion of Menindee Lakes.

One of the Menindee Lakes near Broken Hill in western NSW. Picture: Richard Dobson

Nationals deputy leader Perin Davey is calling for reforms to the Murray-Darling Basin agreement amid warnings additional flows into South Australia could speed up the depletion of Menindee Lakes and risk the Lower Darling River being cut off from the river system.

Senator Davey said the ­Murray-Darling Basin Authority was likely to begin releasing water from Menindee Lakes in NSW into SA within weeks as part of longstanding rules that require water to be flushed down the river system to prevent salinity build-up in the lower parts of the basin.

While the additional dilution flows are triggered when storage volumes in the Hume, Dartmouth and Menindee Lakes were high, Senator Davey said southwestern parts of the river system in NSW were rapidly drying out.

The Bureau of Meteorology is predicting an increased risk of El Nino developing mid to late this year, with it expected to bring on hotter and drier conditions.

Senator Davey said the release of water downstream could risk Menindee Lakes drying quickly and urged commonwealth and state governments to amend the agreement to ensure the Lower Darling could hold on to water for as long as possible.

Any changes to the rules would require agreement from the commonwealth, NSW, Victoria and SA.

“The risks you’ve also got this year, and we’ve seen it in the past in the Lower Darling, is when they rush to release water from Menindee Lakes after a big event (like) we’ve just had, it will actually speed up the depletion of the lakes and the risks is we will get into the next dry phase sooner than we need to,” Senator Davey said.

“We need to be looking at how we manage our water.

“I think now is an opportune time to actually review the ­additional dilution flow rules and see if there’s better way for that water to be used.”

Menindee resident Graeme McCrabb said additional water being sent to SA “didn’t pass the pub test” and warned that mass fish kills could happen again if the river ran dry.

More than a million native fish were killed in 2019, including hundreds of thousands of small bony bream, Murray cod and silver perch, because of a lack of flows in the system.

“SA doesn’t need water at the moment; if we did ­dilution flows at this time, we could risk mass fish kills again in the Menindee Lakes and Lower Darling,” Mr McCrabb said.

Murray-Darling Basin Authority executive director Andrew Reynolds said no additional water was being released from storages. He said triggers were met after flood events to help dilute salinity spikes.