Media Watch Under Scrutiny

MEDIA Watch contacted me on Friday with a barrage of questions concerning my work on the need to restore the Murray River’s estuary. Their line of questioning suggested that I was misleading the Australian public on the important issue of water reform in the Murray Darling. Indeed, the implication was that I am but a stooge for vested interests.

It appears Media Watch is contemplating asserting or implying that my professional judgement and integrity as a scientist has been influenced or corrupted by personal financial gain. Accordingly, I have sought legal advice on the matter, and include this in my full response that can be downloaded here:

https://climatelab.com.au/wp-content/uploads/2026/01/JenniferMarohasy_ReplytoMediaWatch_Amended12March-1.pdf

My responses to their specific questions also follows:

Media Watch: Do you accept that the vast majority of recognised experts on the natural history and hydrology of the Lower Lakes disagree with your conclusion that they were estuarine immediately prior to the erection of the cialis Murray Mouth barrages, or at any time in the past 2000 years?

Jennifer Marohasy: No. The relevant scientific literature, as published in peer-reviewed journals by recognised experts, indicates that the Lower Lakes were estuarine prior to the erection of the Murray Mouth barrages.

The following quote from a scientific paper published in the journal Marine Geology by Professors R.P. Bourman, A.P. Belperio, C.V. Murray-Wallace and N. Harvey, citing E. Barnett, seems to sum up the conclusion of these recognised experts:

“Originally a vibrant, highly productive estuarine ecosystem of 75,000 ha, characterised by mixing of brackish and fresh water with highly variable flows, barrage construction has transformed the lakes into freshwater bodies with permanently raised water levels; freshwater discharge has been reduced by 75% and the tidal prism by 90% (Bourman and Barnett, 1995; Harvey, 1996).”

Professor John Cann and co-workers have studied fossil foraminifera – tiny protozoa with shells of calcium carbonate preserved in the sediments of the Lower Lakes – concluding that the changes in the foraminiferal assemblages over the most recent 2,000 years indicate a general trend of increasing marine influence, up until the construction of the barrages that now block the natural ebb and flow between the Lower Lakes and Southern Ocean.

Professor Peter Gell writing in the recently published The Sage Handbook of Environmental Change has commented that the natural state of the Lower Lakes was tidal, that the lakes have been incorrectly listed as freshwater in the International Ramsar Convention, and that until their natural estuarine character is recognised it will be difficult to reverse the long-term decline in their ecological health.

Geoscience Australia classifies the Lower Lakes as part of a wave dominated barrier estuary with positive annual hydrodynamics.

UPDATE: I have been informed by Media Watch that they will NOT be running their intended program tonight ("This item will not be on this week's show"). It would appear that the possibility of a defamation action coupled with a solid explanation of the science and history of the Lower Lakes has caused Media Watch to change their program. I would like to particularly thank those people who sent emails to Media Watch this morning.

Media Watch: Can you point us to any recognised scientific expert who supports your view?

Jennifer Marohasy: I have already answered this question. But I would like to add some information.

My recent report, Plugging the Murray’s Mouth: The Interrupted Evolution of a Barrier Estuary, focuses on the geomorphology of the Murray River’s estuary. Professors Bourman and Murray-Wallace as quoted in my answer to your previous question, are recognised scientific experts on coastal geomorphology. What they have published in the relevant scientific literature is consistent with my contention that Lake Alexandrina is a Holocene formation and was the central basin of a wave-dominated barrier estuary until construction of the barrages.

In my report I explain that while a rational person, familiar with the available evidence, would likely come to this same conclusion, it is in fact the policy of the South Australian and Commonwealth governments and the Murray Darling Basin Authority to deny this history – to deny this science.

Thus according to the Murray Darling Basin Authority:

“Microscopic analysis of single-celled algae (Diatoms) also provides evidence that in the 7,000 years since they were formed, the Lower Lakes would have been mainly fresh with rare seawater inflows.”

And according to the South Australian government:

"The diatom record in lakebed sediments provides strong evidence that the Lower Lakes have been predominantly freshwater for the last 7,000 years and that seawater ingressions, when they did occur, did not extend north of Point Sturt."

In fact two of the earliest maps of the Lower Lakes, drawn in 1838 and 1844, include comment on water quality and clearly show that waters north of Point Sturt were brackish consistent with seawater ingressions (see Maps 1 and 2 in supplementary material at the above link).

Relying almost exclusively on a single quote in the executive summary of a report commissioned by the South Australian Department of Environment and Heritage prepared by Jennie Fluin, Deborah Haynes and John Tibby, it has become popular for environmental activists, science managers and government bureaucrats to claim:

“There is no evidence in the 7,000 year record of substantial marine incursions into Lake Alexandrina.”

Following the release of my report the South Australian State River Murray Minister Paul Caica said the idea that before the construction of barrages in 1940 the Lower Lakes were predominantly an estuarine environment "is a myth and not supported by science". He was quoted as saying:

"Science based on ... sediment deposited in the Lower Lakes tells us that they have been predominantly a fresh water environment for the last 7000 years."

This claim implies that the modern pre-barrage Murray River estuary represents a steady-state that was formed de novo some time prior to 7,000 years, and which has remained essentially unchanged since. Such an interpretation denies geological and environmental reality, for the scientific literature clearly shows that Lake Alexandrina has a marine origin that dates back to a period of late Pleistocene and Holocene sea level rise (say over the last approximately 12,000 years). During this time the coastal sand barrier and related landward estuarine environments have evolved and changed naturally, including manifold changes in salinity in different parts of the estuarine complex.

Drs Fluin, Haynes and Tibby have published papers discussing the past history of lakes and wetlands based on the presence or absence of particular species of diatom – unicellular algae with bodies of silica – in sediment cores. But their claim that there is no evidence of substantial marine incursions is at odds with not only what we know about how Southern Australian estuaries evolved and now function, but also many studies published in reputable scientific journals including research papers authored by the same scientist, Drs Fluin, Haynes and Tibby. Indeed the claim is inconsistent with the specific diatom assemblage described in their published papers and also in their report to the South Australian government.

The Fluin et al. analysis of diatoms in sediment cores also ignores a large international scientific literature that shows that the majority of reported diatom species have a salinity tolerance in excess of 50 per cent seawater. It is difficult to understand why this critical fact was not discussed by these scientists in their report to government. Most of the diatom species are common in estuaries around the world including in Japan, China, India, Argentina, Brazil, Mexico, the United States, the UK, Portugal, Holland and Sweden.

The Murray Darling Basin Authority has measurements of salt levels in Lake Alexandrina (as measured from the Milang jetty) for the period immediately prior to the sealing of the barrages. This data shows that salinity levels fluctuated and, for example, exceeded 38 per cent seawater level for a period of six months from October 1938 until May 1939, consistent with Lake Alexandrina being part of an estuary. This data also shows that after the barrages were sealed the lakes became permanently fresh. Why has this information been omitted from reports to government?

That the waters of Lake Alexandrina were often brackish during the early period of European settlement, but before the construction of the barrages, is also consistent with newspaper reports from this period and from early maps – as detailed in supplementary information provided in the above link.

Media Watch: It is a central part of your argument that the removal of the Murray mouth barrages would obviate the need to increase environmental flows of fresh water into the lower lakes?

Jennifer Marohasy: Yes. And if I may explain why:

During the recent protracted Millennium drought, water levels in Lake Alexandrina fell precipitously from 0.85 metres above sea level to -1.10 metres below. There was simply not enough water in upstream water storages to keep both Lake Alexandrina and the adjacent Lake Albert supplied with adequate water notwithstanding the Snowy diversions and strictly limited allocations for irrigation during the drought.

To deal with this problem of low lake level and concomitant declining water quality, the South Australian government could have opened the 593 gates within the 7.6 km wide barrage system to allow the ingress of Southern Ocean waters. Instead the South Australian government chose to keep the gates shut tight. This choice was not discussed or reported in the national media in any way. Instead, during the drought, television cameras focused on either the receding lake waters or on the sand dredge working to keep the Murray's mouth open, conveniently avoiding images of the massive man-made sea dykes (known as barrages) that inhibit the cleansing and proper functioning of the former natural estuary system. Media Watch, amongst other public affairs programs, was apparently asleep on this issue.

As soon as the next floodwaters arrived, in the spring of 2010, the government opened the gates to let excess freshwater out.

Melbourne's Yarra River empties into Port Phillip Bay. We don't expect the Yarra River to keep Port Phillip Bay full of freshwater. But we do expect the Murray River to keep Lakes Alexandria and Albert full of freshwater, even during drought. This is a nonsense that has been pounded into our brains, but nevertheless repetition of such an untruth does not make it true.

Interestingly, the Yarra River has 57 per cent of its natural flow left within the river, i.e. available to the environment. Currently the Murray has a similar level of water extraction, with 58 per cent remaining for the environment. In June 2011, the Yarra was short-listed for a prestigious international environmental award, while the Murray River was being described by activist group, GetUp!, as on the brink of ecological collapse because of inadequate environmental flow.

The Murray Darling is a large catchment and the upper Murray and Murrumbidgee are snow fed, so most years the river system can fill Lakes Alexandrina and Albert with freshwater. On average over the 42 years from 1968 to 2010, 5,920 gigalitres a year of freshwater has flowed over Lock 1 which is the last lock on the Murray River before the Lower Lakes, (see Map 3 with the supplementary information). That's about 11 Sydney Harbour's full of freshwater each year flowing into the Lower Lakes.

Media Watch: Obviously this would be in the interests of irrigators and water-rights entrepreneurs upstream.

Jennifer Marohasy: You’ve made a statement. I am not sure what the question is or that I have the necessary expertise to respond. Except to perhaps comment that it is in the interests of all Australians for the Murray River’s estuary to be restored and for the Lower Lakes to be allowed to fill with seawater when the next drought impacts the Murray Darling basin.

Media Watch: In June last year the Adelaide Advertiser and The Land identified Mr Johnny Kahlbetzer of Twynam Agricultural Group as a “supporter” of the Myth of the Murray Group. Was he a financial supporter?

Jennifer Marohasy: Yes. Johnny Kahlbetzer was a financial supporter of the Myth and the Murray Group and this has been declared at the Myth and the Murray website and to anyone who has asked.

Media Watch: Is he, to your knowledge, a financial supporter of the Australian Environment Foundation? Are any other irrigators and water-rights entrepreneurs financial supporters of the AEF?

Jennifer Marohasy: To my knowledge Mr Kahlbetzer is not a financial supporter of the Australian Environment Foundation. I am not privy to the membership or accounts of the Australian Environment Foundation. I would hope there were some irrigators who were financial supporters. I understand there are irrigators who have been financial supporters of the Australian Conservation Foundation.

Media Watch: Have you personally received financial support for your scientific work from any such interested parties?

Jennifer Marohasy: No. I would have liked to receive financial support for my scientific work from such interested parties. Over the last few years my scientific interest in the Lower Lakes has been mostly self-funded. To be clear, Mr Kahlbetzer provided financial support for me to visit Canberra and Adelaide last year as the spokesperson for the Myth and the Murray Group. I declared this support when I met with politicians including through the official lobbying register. Mr Kahlbetzer is not, and has not been interested in supporting my scientific research.

Media Watch: If so, should such support not have been declared in the relevant publications?

Jennifer Marohasy: If such support were provided it would have been declared in the relevant scientific publications.

The Australian Environment Foundation commissioned my recent report on the geomorphology of the Murray River’s estuary. I declared this in the report’s acknowledgements.

Media Watch: Have you received support from other organisations (other than your university and the normal grant-giving academic bodies), such as the IPA or the Heartland Institute?

Jennifer Marohasy: I have never been paid by the Heartland Institute. I worked for the IPA as a salaried employee on contract from 2003 until 2009. During this time I attended a conference on climate change organized by the Heartland Institute.

I have recently published scientific papers including on risk assessment, rainfall forecasting using artificial intelligence and climate change. This work was financially supported by the B. Macfie Family Foundation and is acknowledged as such in the publications. The B. Macfie Family Foundation was established and is run by a Perth-based philanthropist who is concerned that public policy should be evidence-based.

Media Watch: In your recent opinion columns in The Land and you appear to make no declaration to your readers about your long-standing history of public campaigning on the Murray. Do you think you have any obligation to do so?

Jennifer Marohasy: No. My long-standing history of public campaigning on the Murray has grown in part from my arrangements with The Land newspaper. In particular, since 2004 I have written a fortnightly column for The Land and been paid a modest amount for each column. This money has at times over recent years been my only reliable and regular source of income.

I have tried to always write well-researched pieces on issues of relevance to The Land readers. As a consequence over this time I have researched water-related issues. From this research I have come to the considered, though unpopular opinion, that the current $10 billion dollar plan for water reform in the Murray Darling will deliver very little if any environmental benefit, while significantly reducing the capacity of irrigation farmers in the Murray Darling to produce food when there is adequate water in reservoirs.

Media Watch: As a founding member and past chair of the Australian Environment Foundation, do you feel The Land’s description of you as “an environmental writer based in Rockhampton, Queensland” is an adequate explanation of your interest in this issue?

Jennifer Marohasy: The statement is accurate but certainly not a complete description of my interest in this issue. I am a scientist with a PhD from the University of Queensland with interests in a range of important environmental issues. My current position is as a research fellow with Central Queensland University working in collaboration with other recognised research scientists. For example, our recent publication in the journal Human and Ecological Risk Assessment examines the impact of the herbicide Diuron on mangroves. Another paper recently accepted by the journal Advances in Atmospheric Sciences examines the application of artificial neural networks to forecasting rainfall in Queensland. One of our current major interests is the examination of the evidence relating to changes in salinity levels in Lake Alexandrina, South Australia, over the last few thousand years. We are currently finalizing another scientific paper addressing this issue in depth.

I also write for The Land newspaper, with my column published every fortnight since April 2004. It is important for active scientists to communicate with the general public as well as with their fellow professional scientists.

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My entire response, with footnotes and also supplementary information including maps and newspaper quotes, can be downloaded here: https://climatelab.com.au/wp-content/uploads/2026/01/JenniferMarohasy_ReplytoMediaWatch_Amended12March-1.pdf