FLOODS in north-west NSW, dust storms in the south-east—a familiar pattern that elicits a familiar response: why not capture all that flood water and send it south?
It’s been about 70 years since the designer of the Sydney Harbour Bridge, Dr J. Bradfield, conceived a program for harnessing the water rushing down the rivers of north Queensland and sending it inland to irrigate new lands and to supply urban centres as far away as Adelaide.
Variations on the idea have reflowered—and died—ever since.
But the concept has never been sown in such a fertile political environment as exists today.
The dire condition of the Murray River, the urban and irrigation communities that depend on it, and the ongoing consequences if this is a foretaste of climate change, are encouraging fresh thinking.
Long-distance water transfer proposals have been given serious consideration several times already this decade—not to service irrigation areas, but to top up depleted urban water supplies.
Adelaide, which, with most of South Australia is umbilically linked to the ailing Murray, has considered the issues around transferring water from the Clarence River (NSW), to north-east Queensland, the Ord River (WA) and the Great Artesian Basin.
Horrendous costs, and the political challenges of stitching up trans-State water rights and land tenure, turned Adelaide toward desalination instead.
Perth took the same route after the WA Government commissioned a major feasibility study into sourcing water from the under-utilised Ord River scheme.
A best guess was that Ord water would land in Perth at a cost of at least $6.10 per kilolitre.
Desalination cost around $1.11/KL.
In 2007, Brisbane and the extended urban communities of south-east Queensland, contemplating steadily-depeleting dams, looked thirstily over the border at the Clarence River in northern NSW.
A major study by the National Water Commssion plotted possible pipeline routes, but in the end concluded that the flows in the Clarence were too unreliable—and might grow more unreliable under climate change—to justify the outlay in infrastructure.
But none of this has dissuaded Terry Bowring, the driving force behind the latest idea to irrigate the south from the north.
Click here to read Mr Bowring's detailed proposal
Mr Bowring, a Sydney-based consultant chemical engineer, is the latest in a long list of people who have thrown themselves behind a water transfer scheme out of a deep conviction it is the only answer to the issues at stake.
“Victoria and South Australia are in deep trouble, and may be in deeper trouble in years to come,” Mr Bowring said.
“There’s talk of taking agriculture north to the rain, but that’s full of problems.”
Mr Bowring’s comprehensive “Multi State Water Transfer Project” proposes that about 4,000 gigalitres (GL)—slightly under the long-term average storage capacity of the Murray storages—be siphoned off the Burdekin and adjacent rivers and sent 1,500 km south in lined canals to about Bourke.
From Bourke, subsidiary pipelines or canals would take water past the evaporation pans of Menindee Lakes and dump it into the Darling, to be take south by gravity.
Other subsidiary lines would feed Brisbane and Sydney, and any irrigation areas that the market deemed viable to run from the canal.
According to Mr Bowring, an average of about 11,600 GL a year currently flows out to sea from the Burdekin River. His extraction plan would take about a third of that, although some could be taken from other rivers.
Rough costings on a pipeline to carry water across the main 1500 km section of the scheme came to about $32 billion—prohibitively expensive.
Mr Bowring then looked at canals lined with concrete or synthetic linings, a technology he has seen at work in the United States, and came up with around $5.6 billion to get water from the Burdekin to Bourke.
He suggests that the canal route be sited to take advantage of existing and proposed gas pipelines, which could deliver the energy needed to shift such huge volumes of water.
In order to average out seasonal flows, Mr Bowring’s proposal suggests that excess water should be stored in “fractured rock aquifers” such as the huge Gilbert River Aquifer in north Queensland.
Using a system to hold water over the fractured rock zone would allow water to enter the aquifer at a seepage rate of a couple of metres a day, he claims. Once underground, it is stored indefinitely away from evaporation.
“So long as you keep very good records about what you’ve put in, there should be no argument about what you can extract,” he said.
Mr Bowring and his supporters have submitted rough proposals to the Victorian Government, the Federal Senate, and concrete industry majors in the hope of getting funds for a full feasability study.
“Australia has to think about, debate, and make decisions about its long term future,” he said.
“The way we value, allocate and manage water will have major impact on the quality of our future.”
* Contact Terry Bowring: t.b.a@bigpond.com
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