Lower Lakes study announced by MDBA

By Geoff Adams

The status of the South Australian Lower Lakes as fresh or saline bodies of water is expected to come under scrutiny in an independent scientific review announced by the Murray-Darling Basin Authority.

Victorian irrigators, the National Party, and State Member for Shepparton Suzanna Sheed have been agitating for the review for months because the lakes consume so much fresh water from the Murray River.

Scientist Peter Gell has written a report outlining how the lakes have historically been saline, whereas the lakes have been managed in recent times as freshwater, which has required large flows of Murray River water.

About 700 to 800 Gl of water evaporates from the lakes every year.

Ms Sheed raised the issue in Victorian Parliament in August and now she is looking forward to an independent assessment of the science around the management of the lakes.

Although the announcement did not mention Prof Gell's work, she hopes and expects it will be examined.

“The MDBA often says it is working on the best available science; here is an opportunity to put that to the test,” Ms Sheed said.

“The review needs to be fulsome and broad enough to cover all the issues we have been raising.”

Victorian shadow water minister Steph Ryan said she was pleased to see the Federal Government had acted on the request from the Victorian Nationals for a re-examination of the science.

“There are justifiable concerns that South Australia’s arguments are based on political expediency rather than science,” she said.

“The detailed work undertaken by Prof Peter Gell throws significant doubt on South Australia’s claim that the Lower Lakes are a predominantly freshwater ecosystem.

“We can’t afford to let 900 Gl of water evaporate from the Lower Lakes every year while communities are facing ruin from a lack of available water,” Ms Ryan said.

Prof Gell’s report shows the science-based position is that the Lower Lakes were always a mostly estaurine system that only occasionally became predominantly freshwater during large flood events.

‘‘This only changed to predominantly freshwater once the barrages were put in,’’ he said.

The review will be undertaken by an independent team led by Australia’s leading science agency CSIRO and assisted by the MDBA’s Advisory Committee on Social, Economic and Environmental Sciences (ACSEES).

MDBA's Partnerships, Science, Knowledge and Engagement executive director Carl Binning said the MDBA was committed to openness and transparency and welcomed the recent debate about Lower Lakes management.

“We’re confident in the way governments are managing the Lower Lakes but know there is renewed community interest in all aspects of water management, which is why we wanted this review to take place,” Mr Binning said.

ACSEES chair Professor Rob Vertessy said ACSEES looked forward to working with the review team.

“The Lower Lakes and Coorong are a vital asset and of great cultural significance to the Ngarrindjeri Nation and the First Nations of the south-east.

“The wetlands are internationally recognised, supporting endangered migratory birds, threatened wildlife and rare plants. The lakes also support a thriving agricultural sector. Therefore, it’s critical that the Lower Lakes are well managed,” Prof Vertessy said.