Authorities are warning landholders downstream of the Hume Dam near Albury-Wodonga to prepare for flooding as spring approaches.
- The Murray River system has reached full allocation for river operators the earliest time in 20 years
- Hume and Dartmouth dams are expected to fill
- A wetter than average spring has been predicted
Up to 100 millimetres of rain is predicted this week in Victoria's north-east and the New South Wales Southern Riverina region with Upper Murray, Mitta Mitta, Kiewa, Ovens, and King rivers expected to see flooding.
After a fairly dry July, Hume Dam is sitting at 92 per cent capacity and is expected to fill this season.
The dam filled in September last year.
Yesterday the Murray-Darling Basin Authority (MDBA) advised landholders downstream from Hume Dam "to be flood ready as we enter the wettest period for southern basin catchments".
MDBA executive director of river management Andrew Reynolds said the Hume Dam currently had 250 gigalitres of airspace available before the dam was considered full.
"We've been in close contact with the Bureau of Meteorology, we're anticipating that we will be able to manage this rain event with the airspace that we have got," Mr Reynolds said.
"We will make further releases to preserve further airspace in advance of future events."
Farmers downstream of Hume Dam said the abundance of water already in the system was "very concerning".
Chairman of the Murray River Action Group, Richard Sarsgood, said landholders along the Murray would be checking storages levels every day in anticipation of flooding.
"Everybody is watching this coming rain event and we'll see how much airspace it soaks up in Hume Dam," he said.
"By the next rain event people will start looking at moving stock to higher ground or out on agistment."
Murray at full allocation
Irrigation season officially starts on August 15. Already, Victorian irrigators have their 100 per cent high reliability allocation.
Resource manager with Goulburn Murray Water, Mark Bailey, said this was the earliest the system had reached full allocation in 20 years.
"The last time we were at this level was 2002/2003. It's something that we haven't seen in a very long time, " Mr Bailey said.
Authorities are anticipating a wetter year, warning irrigators and landholders to expect more water.
"It's something that makes a river operator quite nervous in terms of what's happening with potential inflows and where the dams are," Mr Bailey said.
'High probability' Dartmouth will spill
Further upstream from Lake Hume, Victoria's largest capacity dam in Dartmouth is sitting at around 95 per cent capacity, holding 3.8 million megalitres of water.
The last time Dartmouth dam spilled was in October 1996, and excitement has been building that the mega dam could overflow for the first time in more than a quarter of a century.
"There's a reasonably high probability that Dartmouth will fill this year," MDBA's Andrew Reynolds said.
"It is a much bigger storage than Hume, however it's also has a much smaller catchment upstream, so the inflows are not necessarily as large.
"We're not pre-releasing water from Dartmouth because it would just make its way into Hume and we would have more water to manage there.
"At the moment it's better that we protect the airspace at Hume Dam."
Living on the floodplain
Richard Sarsgood has been farming along the Murray River outside Howlong, NSW, for 66 years.
Among the 120 members from the River Action Group living between Lake Hume to Yarrawonga, Mr Sarsgood said there was a higher concern for flooding this year with an abundance of water already in the system.
"There's a lot of concerned landholders and tourism operators because the system has been fully charged since February," Mr Sarsgood said.
"With the rain event this week, and future events, there's a lot of concern there's going to be repeat flooding like in previous years.
"To the MDBA's credit, they have drawn Hume dam down to 92 per cent which is a step in a right direction.
"However with Dartmouth so full, and the Bureau of Meteorology predicting a wetter than average next three months, we are really concerned the flooding will be heading our way."