THE resumption of dredging at the Murray Mouth is being billed as a "stark reminder" of why South Australia needs 450 gigalitres of environmental flows promised under the Murray-Darling Basin Plan.
It is the first time dredging has been carried out since the River Murray floods of late 2022, early 2023.
The state government said recent dry weather meant sand had started to build up again at the Murray Mouth and dredging was needed to protect the health of the Lower Lakes and Coorong.
"While the floods provided an ecological lifeline to the Coorong and Lower Lakes, forecasts now indicate we are poised for a drier period in the foreseeable future," SA Environment and Water Minister Susan Close said.
Dredging is used to remove the build up of sand at the Murray Mouth and two adjacent water channels, ensuring a clear passage of water flow between the Southern Ocean and River Murray system.
It is estimated more than 14 million cubic metres of sand has been removed at the Murray Mouth since 2002.
Dr Close said the need for dredging was a result of the failure of upstream states to ensure enough water was flowing down the system and a stark reminder of the need for 450GL of environmental flows under the MDB Plan.
The Basin Plan has been in the spotlight recently, with the federal government's re-write of the plan hotly debated in parliament and by irrigator groups, local councils and farming organisations across the country.
Much of the debate has centred around buybacks, with many eastern states groups and councils heavily opposed, while SA groups are more circumspect.
"Ideally, the mouth of our country's biggest river should not need to be dredged continuously to keep it open," Dr Close said.
"This is just another expense caused by the failure of upstream states to ensure enough water flows down the system to ensure the health of the whole river system.
"This is why it is so fundamental that the Murray Darling Basin Plan, including the 450 gigalitres of environmental flows, is delivered in full."
