Murray Mouth, Coorong, Lower Lakes, still not getting enough water

Almost 4 million cubic metres of sand have been dredged from the Murray Mouth this year, compared to about 2.5 million at the same time last year.

• Murray carp may recover, return after herpes virus release

Almost four million cubic metres of sand has been dredged from the Murray Mouth this year, compared to about 2.5 million at the same time last year.

Keeping the Murray Mouth open is vital to the river system’s health, and one of the key goals of the Murray-Darling Basin Plan is to deliver enough water to do that without dredging 95 per cent of the time.

For now, two dredges are operating 24 hours a day.

Dredging is done to make sure water flows in and out of the ocean, which allows salt to be flushed out and cooler, oxygenated water to come in and keep the Coorong healthy.

The Murray-Darling Basin Plan has come under fire from all directions this year.

There have been allegations of water rorting and theft, and a state royal commission has heard from a range of witnesses questioning the science behind the plan’s aim to save 3200 gigalitres of water a year.

South Australia is at the end of the system and therefore the most vulnerable to reduced water. The Lower Lakes, the Coorong and the Murray Mouth are at the core of the concerns.

A month ago, a report from the Goyder Institute found the Coorong was “vulnerable” and risked losing key elements that made it an internationally important wetland. Algal blooms are affecting native plants, in turn affecting the number of waterbirds.

At the time, State Water Minister David Speirs said that while the Coorong had been on the brink of collapse during the Millennium drought, it was “slowly recovering”.

But a parliamentary report released yesterday — the Inquiry into the management and use of Commonwealth environmental water — also heard that increased flows to keep the Murray Mouth open and the Coorong healthy increased the risk of flooding on private property as the water flowed through.

“There is no doubt that getting larger flows through the system is required to move the body of sand that sits at the Murray Mouth to keep the Murray Mouth open,” Murray-Darling Basin Authority spokesman Carl Binning said in response to concerns about flooding, particularly from NSW landholders.

Rosa Merlino-Hillam from the River Lakes and Coorong Action Group said the Coorong was now looking “OK” but was still “in recovery”.

Late yesterday, Mr Speirs took his federal counterpart David Littleproud on an aerial tour of the Coorong.

The tour comes ahead of a Ministerial Council meeting on the Murray next week.