'Like a kid at Christmas': Menindee Lakes finally start to fill again

Residents of far-western NSW are celebrating the arrival of the first major river flows to reach the Menindee Lakes since 2016.

The region, site of a series of mass fish kills just over a year ago, began receiving flows down the Barwon-Darling River after big rains further up the system in recent weeks.

Graeme McCrabb, a grape grower who helped draw publicity to the deaths of a million or more fish in his area, said he spent all day on Tuesday with his wife, Maree, watching the water come down the river.

"I was like a kid at Christmas," Mr McCrabb told the Herald. "It means a fish can swim all the way from here to Goondawindi - but it's a bit out of my league."

NSW Water Minister Melinda Pavey said water began entering Lake Wetherell, one of the Menindee Lakes, on Wednesday, with much more to come.

"The volume and extent of the flow generated by rain - and not dam releases - is by far the best naturally occurring flows in the Barwon-Darling since the floods of 2016," Ms Pavey said.

The first major river flow to arrive in the Menindee Lakes and in the main weir since 2016 arrived on Wednesday.

"Lake Wetherell could see inflows of between 230 and 260 gigalitres, equating to more than 12 months of town water supply for the Lower Darling, and we are expecting to see much more water flow into the Menindee Lakes over the coming weeks and months," she said.

"It’s a relief to see this water replenishing parts of the state that have arguably endured the longest and most severe of the drought conditions."

Mr McCrabb was a member of several local groups that have battled to keep alive local stocks of endangered Murray cod and other threatened native fish, such as golden perch, as waters dried up or became deoxygenated.

This week, he has been helping to remove three of the six aerators locals and authorities installed at different sections of the river to help fish survive. The groups also regularly rescued and relocated fish, moving at least 150 Murray cod alone.

Graeme McCrabb on his tinnie in the Darling River, floating among dead Murray cod and other fish just after the second of three big fish kill events near Menindee in January 2019.Credit: Nick Moir

"It's been endless," Mr McCrabb said. "It hasn't let up for the whole time - I'm looking for a spell."

The Darling, also known as the Barka, still needs a lot more water, though, to regain its former health.

"It's going to take a long time before the water gets to the Murray, [about 230 kilometres downstream from Menindee]," Mr McCrabb said.

The water will build between the lakes and Weir 32 near Menindee before probably spilling over the wall in the next couple of weeks.

In January 2019, dead and dying kangaroos, goats and sheep were seen stuck in drying mud in the drainage canal of Lake Cawndilla, one of the four main lakes of the Menindee system that is now beginning to fill again.Credit: Nick Moir

"The day it flows over Weir 32 will be a great day," Mr McCrabb said.

Lee Baumgartner, a fisheries expert at Charles Sturt University, said the waters returning to the lakes was "good news - we've been waiting for this for two years".

He said the fish coming down the river would get a chance to recolonise areas hit by fish kills in 2019, although "it's pretty late for spawning" this year.

Professor Baumgartner praised the Berejiklian government for placing an embargo on extraction of most of the flows.

"It's the first time we've had an event managed like this," he said. "It was a really positive step."

Still, the Murray-Darling Basin rivers still need a lot more rain to ensure their recovery continues.

"We desperately need some more follow-up rains to fill the system," Professor Baumgartner said.

Cameron Lay, a habitat manager with the fisheries unit of the Department of Primary Industries, said he "was amazed at how resilient these systems are", noting how everything from insects and frogs to large schools of fish have appeared soon after the flows arrived.

Rescuers saved some 1400 fish - mostly Murray cod and some golden perch - from the Darling River. Many were taken to the Fisheries hatchery hundreds of kilometres away at Narrandera, where they will be kept for five years for breeding.

Teams will take fingerlings from the hatchery back to the Darling in spring, if conditions are right, Mr Lay said.

Researchers will stain the bones of the fish to see where they travel and how they fare.

Agencies will hold a meeting on Friday to decide when and how the temporary block banks on the Lower Darling will be removed to allow flows from Menindee to join up with the Murray near Wentworth, Mr Lay said.