It is expected recent flooding in northern New South Wales and Queensland will deliver some water to the Menindee Lakes - but not as much as the past two years.
The New South Wales Office of Water says there has been some rainfall in the Gwydir and the Namoi Rivers, which could reach the Lakes by the end of next month.
But the office's Michael Wrathall says it will not be as much as the thousands of gigalitres that reached the lakes last summer.
"We're expecting these flows to start entering the Barwon River, and then once they reach the Barwon River we'll have a better idea of the extent of what will go through Bourke, and then on to Menindee," he said.
"But we're expecting in the order of tens or hundreds of gigalitres to reach Menindee Lakes for this event as it stands."
© ABC 2013
16:39 EST The mercury soared in the nation's southwest today with Perth recording its hottest September day on record, however heavy rain and cooler temperatures will arrive on Sunday.