YESTERDAY the South Australian government yet again displayed its contempt for science and history by claiming yet again that Lake Alexandria is, and always has been, a freshwater lake.
I’m hopeful that the local tabloid, the Adelaide Advertiser, will publish my reply. So far this News Ltd publication has refused to let me respond to various articles about me.
My Letter to The Editor:
Paul Caica, South Australian Minister for Water and the River Murray, claims that in wishing to restoring the Murray River estuary, I show disrespect for scientific work and the culture of the region’s traditional owners, the Ngarrindjeri (Lakes flood plan defiles the existing evidence, Adelaide Advertiser, March 31, 2009).
In fact, all the science published in peer-reviewed journals is on my side. Minister Caica’s claim is consistent with the Book of Genesis in the Bible inferring the estuary came ready-formed with a sand barrier and central lagoon. But such an interpretation denies geological and environmental reality. The scientific literature clearly shows that Lake Alexandrina has a marine origin that dates back to a period of late Pleistocene and early Holocene sea level rise. Since this time the coastal sand barrier and related landward estuarine environments have evolved and changed naturally, including manifold changes in salinity.
The Murray Mouth barrages were built to stop saltwater intrusions that were a problem from the time of European settlement. Indeed, long before the development of upstream irrigation, the Southern Ocean would push in each autumn and for longer periods during drought.
The seawater poured in through the Murray’s mouth and sometimes worked its way across the lake and then into the River Murray proper as far north as Mannum. This is recorded in the patangi – a song category of the Ngarrindjeri. In one of these stories, the River Murray drags trees along as sea water flows upstream as far as Mypolonga. The river water was too salty to drink and the Ngarrindjeri were forced to dig wells about two feet deep to get drinkable water.
Minister Caica really should read more and/or consult more widely to avoid making foolish statements.
Biologist, Noosa, Queensland
 Article by Minister Caica
Lakes flood plan defies the existing evidence
Queensland biologist Jeniffer Marohasy would have Australians believe that removing the Barrages at Goolwa, near the mouth of the River Murray and letting seawater flood into Lake Alexandrina and Lake Albert should be at the heart of the draft Murray Darling Basin plan.
Dr. Marohasy recently released a report called Plugging the Murray River’s Mouth, which was commissioned by the Australian Environmental Foundation (AEF) of which she is a member.
To support her recommendations Dr. Marohasy asserted that the Lower Lakes were not a freshwater environment before European settlement.
This defies the respected scientific work on this matter. Science based on the study of diatoms (microscopic single-celled algae) in sediment deposited in the LL tells us that they have been predominantly freshwater environment for the past 7000-years.
Dr. Marohasy claims also contradict the culture and wellbeing of the region’s traditional owners, the Ngarrindjeri, which for thousands of years have been directly tied to the water in the Lower Lake’s system being fresh.
Dr. Marohasy’s report also ignores the devastating consequences of flooding the Lower Lake with sea water.
The SA Government investigated this during the recent drought and found that acidity would mobilise, and heavy metals would be released, if sea water was allowed to flow into the Lower Lakes.
Hypersalinity would occur threatening the security of water supplied to Adelaide and country towns.
The ecology and economy of the Coorong and the Lower Lake’s region would be decimated, with native fish, plant and bird species becoming extinct.
While the scant regard for downstream communities and the environment is worrying, what is more alarming is the apparent attempt to distort the public debate on the crucial debate of our nation’s iconic system.
Other respected scientists have discredited the work, with one stating that “science should not be twisted to support a poorly supported and dangerous policy option.”
Even the scientist claiming to have peer-reviewed the report by Dr. Marohasy has admitted on ABC’s Media Watch on Monday that he was a friend and was “happy to accept” he may not have seen all the flaws in her argument.
The SA Government has been advocating for a Murray Darling Basin Plan that is based on science.
Our own scientific work analysing the plan is being independently reviewed by the Goyder Institute for Water Research. The State Government will continue to advocate that it is essential to treat the science that helps inform policy decisions with respect. [end of article]