Millions to strengthen SA levees as River Murray flow prediction jumps
River Murray flows from flood-hit Victoria into South Australia are now forecast to reach 135 gigalitres per day by early December – 15 gigalitres higher than predicted just last week – as the state government commits $3 million to shore up Riverland levees.
Deputy Premier Susan Close. Photo: Jason Katsaras/InDaily
Deputy Premier Susan Close announced a short time ago that ongoing rainfall in Victoria has prompted the state government to revise its forecast for daily River Murray flows into South Australia from 120GL to 135GL.
The 135GL daily flow is expected to reach the Riverland by early December. Close said it is “possible that that that figure will go up with further rain events in Victoria”.
“It’s also quite likely that if there’s further rain further north in the northern parts of the Basin and the northern parts of Victoria, than rather than being a much higher figure it will be that amount of water coming for a longer period,” she told reporters.
“This is crucial information for people who live in the Riverland, and I urge them to continue to use the service that’s available via the Environment Department’s website to be able to look at their own properties and see the impact of different levels of water coming through.”
Flows to SA were previously expected to reach about 85GL per day around October 28, continuing to rise during November before reaching 120GL per day in early December.
The revised flow forecast would mean the Paisley Creek region in Blanchetown could come under threat of flooding, with modelling predicting the area would come under threat at 140GL of daily flow.
Water rises at Loxton at a marker for previous River Murray flood levels. Photo: Belinda Willis/InDaily
Close said Riverland residents should be “not alarmed but prepared and alert”.
She said the state government would make $3 million available to bolster the Riverland’s flood levee system.
“We’re aware that there are some concerns about the levee system throughout the Riverland, in particular two levee banks that have been drawn to our attention very early on in Renmark,” Close said.
“The government’s therefore determined to allocate $3 million initially to work with councils – primarily the Renmark council but not exclusively – to work through being able to remedy the gaps in those levee banks.
“So that as we get over the 130 gigalitres that was being identified previously as a challenge for the levee banks, that we are prepared to be able to withstand the water lapping over the edges.
“The hospital bank, for example, at 130 gigalitres will start to require the levee bank to be intact – if it has gaps, that is the point at which the water will start to flow through.
“So we’re now in a position where that is very likely to be the position in early December, and therefore we need to make sure that the remediation works have been undertaken.”
Susan Close and I met with the Riverland and Murray Lands Coucils to discuss our collective efforts in preparing for upcoming flows through the River Murray.
The State Government has made an immediate allocation of $3M to begin the works known to reinforce and repair levees. pic.twitter.com/bgVwDkeagP
— Joe Szakacs MP (@joe_szakacs) October 27, 2022
Renmark Paringa Council has been stripping vegetation from the hospital bank in preparation for major engineering works on the levee.
River Murray town mayors and CEOs gathered in Adelaide today to meet with the SES and state government ministers to talk about preparations for potential flooding.
A Riverland levee bank on October 22. Photo supplied
State Emergency Service chief officer Chris Beattie said the SES has responded to “just shy of 300 incidents” over the past week.
“The hardest hit communities in South Australia were the Mid North and the Riverland, with localised flooding across the Wakefield River, Lower Light and also parts of the Gawler River,” he told reporters.
“Within the Riverland, a very heavy rain event in Renmark in particular led to localised flash flooding also.”
Beattie said Renmark was “the most exposed” to the rising River Murray flows but “it’s got the most extensive levee bank around it”.
“The levees themselves were designed for a 210 gigalitre flow event, which is what the state experienced in the 1930s,” he said.
“Our hydrologists say that at 130 gigalitres the levees are doing their intended work and they’re taking the weight of the river.
“At 135 [GL] the levees will be doing their job in terms of holding the river back from the urban areas.”
Beattie said the latest flow forecast “takes into account the water that’s in the system now” but does not account for “any predictions around future rain events”.
“It’s not beyond the realm of possibility that we continue to see an increase in these forecasts if we see more rain in the eastern seaboard,” he said.