RECENT billion-dollar plans for the Murray Darling Basin have never been about the environment. Rather they have been about special interest groups doing deals through constant negotiation, with commercial interests in South Australia generally trumping all others.
As Geoff Adams recently explained – with his newspaper article republished in various regional newspapers – Waterfront houses on Hindmarsh Island and its marinas sell for between $500,000 and more than $1 million. Some of this real estate has been planned around the marina where jetties are built to a fixed sea level height, never mind that without the barrages the lake is a naturally tidal estuary, that could be swamped by global warming.
I could go on … but suffice to say there is nothing sustainable about any of the planning for so many years for the precious fresh water from upstream.
Any rational solution must begin with the dismantling of the 7.6 kilometres of barrages built in the 1930s in an attempt to convert the Murray River’s estuary into a play lake for Adelaide’s elite … to go yachting and water skiing. I’ve written about this many times, including in a 2012 report, which can be summarized:
The Australian Government’s $10 billion tax-payer funded plan to save the Murray-Darling by channeling water from upstream water storages and flood plains to the Lower Lakes, Murray’s mouth and Coorong, is based on a false premise; a misunderstanding of the fundamental nature of the Murray River’s estuary and the coastal processes that continue to shape it.
The Murray River’s estuary was formed 7,000 years ago during a period of rapid sea level rise. It was in an intermediate stage of evolution with the central lagoon developing from intermittently closed to fully tidal, when in the 1930s, sea dykes/barrages were built between the island, just to the north of the sand peninsula and the narrow entrance to the Southern Ocean.
These sea dykes dammed the estuary, stopping the tides, and made the lagoon/Lake Alexandrina totally dependent on Murray River flows. After the Mundoo channel was blocked through the construction of that barrage, sand that shoaled around the Murray’s mouth consolidated creating a new island, Bird Island.
Long-standing government policy and vested interests preclude discussion of the coastal processes that are growing Bird Island that may one day permanently block the Murray’s mouth… inevitably flooding the marina at Hindmarsh Island, and its associated expensive real estate.
Back in 1856, South Australia’s Surveyor General George Woodroffe Goyder recognised the potential of the Mundoo channel to scour the Murray’s mouth. He suggested the natural process of deepening and widening of the Murray’s sea mouth be enhanced by cutting though the rock bar across this channel thus further concentrating tidal water inflow and river water outflow. Instead, over the last 156 years government policy has worked to stop the tide and block the channel – but it’s not too late to change direction and restore the estuary and bring back the tide.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Publication of the 2012 report caused the Australian Broadcasting Corporation to defame me on Media Watch.
They ignored my detailed and rational response to their questions, and just made-stuff-up, as they continue to ignore the existence of 7.6 kilometres of sea dyke/barrages and spin a false narrative about the Murray River and its mismanagement. This is because our national broadcaster acts mostly in the interest of the elites, and their often obscure agendas.
And even upstream it’s salty. When Sturt in 1838 couldn’t water his horses at the junction of the Darling because it was too salty.
These so-called environmental flows don’t happen naturally in a drought.
Fake environmentalism. At taxpayer expense!
The Darling is salty in some places during low flows because the local water is dominated by groundwater inputs from salty aquifers. Mitchell found freshwater both upstream and downstream from salty water in the river
I always wonder about the contrast of Lake Alexandrina … an artificial fresh water lake and the Gippsland Lakes which were freshwater, until an entrance was created at Lakes Entrance making all the lakes brackish.
Although I’m a South Oz by birth, and even voted for the Chowilla Dam up stream of Renmark, 50 odd years ago, thank heavens it was never built as it would have been an unnatural disaster of catastrophic proportions, much like that huge man-made edifice on the Nile, aka Aswan Dam.
Using 2 m of evaporation pa the Lower Lakes and Coorong evaporate 780 Gigs pa
Assuming 500 mm of rainfall
In a drought year the inflows into the entire MDB are around 10,000 Gigs
So that’s 8%
However it takes 7-8 Gigs released from Hume or Eildon storage’s to get 1 into the Lakes,
So that’s 60 odd % of the inflows!
These aren’t ‘environmental flows’ at all, they are political flows!
There is an answer
Throw a bank 200m from the edge of the Lakes to form an irrigation channel and reflood the centre of the Lakes by removing the barrages!
You can even sell the reformed land for real estate with fresh weather one side and salt the other!
No acid sulphate soil issues ( like it doesn’t occur elsewhere in the MDB) and honouring Ramsar Conventions on migrating birds ( like that doesn’t occur elsewhere in the MDB!!!)
Great piece!!!
south Australia constitutes 14% of the MDB but looking at the electorates in the Basin it’s about 84% of the votes!
And maybe 12% of the inflows!
Yet SA is on 100% allocation even selling some of its “environmental flows” on the temporary market for $600 /meg
It’s a cash cow for the Adelaide elite and it’s time it was over!
the process is CORRUPTION writ large.
It is about time this was yelled from the rooftops, for too long these drongos have got away with flushing country Victoria and NSW water down the toilet. Claiming water is needed to keep the Murray mouth open. What for? To let salt water into the Coorong which they claim is too saline. Yes enough is enough , a Royal commission into this con is the only answer.
Peter Andrews had a plan for rejuvenating the mainstream Murray et al, by re-introducing the Australian-style of wetlands all down the mainstream. This also slows down the water and causes local overflow during flood-years. I would guess that the works needed would include diversionary basins at overflow points to control the flooding.
Logically, the mechanics of it support the concept of saline lower lakes.
There is a thing at Sydney University tomorrow(Thursday 9 May) on the Murray-Darling, which will be a leftie luvvy-fest at 6.30 pm at the old Geology school. They probably have booked all the seats, but a lot of no shows, so you nearly always can get in. I am booked. Please ask questions about why should the barrages be maintained to destroy a functioning estuarine system? Why should irrigators ,who produce a very significant amount of Australia’s agricultural output be deprived of water to create a fresher water lake for a few elites downstream?