Authorities are warning property owners downstream of the Hume Dam near Albury-Wodonga to prepare for flooding as spring approaches.
Key Points:
- Murray River system reaches full allocation for river operators for first time in 20 years
- Hume and Dartmouth dams are expected to fill
- A wetter than average spring is forecast
Up to 100 millimeters of rain is forecast this week in north-east Victoria and the Southern Riverina region of New South Wales, with the Upper Murray, Mitta Mitta, Kiewa, Ovens rivers expected to and King see floods.
After a fairly dry July, Hume Dam is at 92% capacity and is expected to fill this season.
The dam was filled in September last year.
Yesterday, the Murray-Darling Basin Authority (MDBA) advised landowners downstream of Hume Dam “to be prepared for flooding as we enter the wettest period for catchments in the southern basin”.
MDBA executive director of river management Andrew Reynolds said Hume Dam currently had 250 gigalitres of airspace available before the dam was considered full.
“We have been in close contact with the Bureau of Meteorology, we anticipate that we will be able to manage this rain event with the airspace that we have,” Reynolds said.
“We will do more launches to preserve more airspace before future events.”
Farmers downstream of Hume Dam said the abundance of water already in the system was “very concerning”.
Murray River Action Group chairman Richard Sarsgood said landowners along the Murray would review storage levels every day in anticipation of flooding.
“Everybody is watching this rain event and we’ll see how much airspace it takes up over the Hume Dam,” he said.
“In the next rain event, people are going to start looking at moving the stock to higher ground or exiting with agitation.”
Murray in full assignment
The irrigation season officially begins on August 15. Victoria irrigators already have their high reliability allocation at 100%.
Hume Dam reached capacity in September 2021 for the first time since 2016. (ABC Rural: Annie Brown)
Goulburn Murray Water resource manager Mark Bailey said it was the first time the system had reached full allocation in 20 years.
“The last time we were at this level was in 2002/2003. It’s something we haven’t seen in a long time,” Bailey said.
Authorities are predicting a wetter year, warning irrigators and homeowners to expect more water.
“It’s something that makes a river operator pretty nervous about what’s going on with potential inlets and where the dams are,” Bailey said.
“High probability” that Dartmouth will spill
Further up Lake Hume, Victoria’s largest dam at Dartmouth is at around 95% capacity, with 3.8 million megalitres of water.
Darmouth Dam is Victoria’s largest reservoir with a capacity of 4 million megalitres. (Rural ABC: Annie Brown)
The last time Dartmouth Dam spilled was in October 1996, and there has been excitement that the mega dam could overflow for the first time in more than a quarter of a century.
“There is a reasonably high probability that Dartmouth will fill up this year,” said MDBA’s Andrew Reynolds.
“It is a much larger storage than the Hume, but it also has a much smaller catchment upstream, so the inflows are not necessarily as large.
“We are not pre-releasing water from Dartmouth because it would just go to the Hume and we would have more water to manage there.
“For now, we’d better protect the airspace over Hume Dam.”
Living in the flood plain
The Murray system has reached full water allocation. (Rural ABC: Annie Brown)
Richard Sarsgood has been farming along the Murray River outside Howlong, NSW, for 66 years.
Among the 120 members of the River Action Group who live between Lake Hume and Yarrawonga, Sarsgood said there was increased concern about flooding this year with a large amount of water in the system in August.
“There are a lot of owners and tour operators concerned because the system has been fully loaded since February,” Sarsgood said.
“With this week’s rain event and future events, there is a lot of concern that there will be repeat flooding like in previous years.
“To the MDBA’s credit, they have reduced the Hume Dam to 92%, which is a step in the right direction.
“However, with Dartmouth so packed and the Met Office forecasting the next three months to be wetter than average, we are really worried that flooding will be headed our way.”