Colin,

Nice diss attempt.

Readers may want to consider:

* It is 300 Km from the deepest part of L Eyre to Pt Augusta.

* An initial project will seek to flood the canal and L Eyre. An area only big enough to be covered by shadecloth will be flooded. The cloth design will control evaporation rate and collect condensation to water 3 strata of native vegetation along the channel and around any flooded areas.

* The extent of area cooling will initially be small. It will grow in line with revegetation of watered areas about the project.

* Revegetation will be extensive and an important part of the planning will be to involve volunteers and schools in a program to 'Reseed the Heart'.

* As well as the canal, some piping will be required to pump water to selected sites for revegetation.

* The project would begin with a pilot study in L Torrens to test the solar desal concept, the shadecloth, the amount of evaporation and its impact on localised natural precipitation, the revegetaion regimes and the provision of water to local farmers and tribal stakeholders.

* Lake Eyre WAS permanently flooded some 10,000 years ago when the area was burgeoning with life. There is a precedent for this project's success. How far we can return the area to that ancient condition and its ultimate impact on climate in the eastern states will need to be assessed via modelling and by the pilot project described. The stakes are high for this country and it will require some bold leadership to reach deep into the continent's history to reseed the heart of Australia.

* And as confucius said " A journey of a thousand miles (or 300Km) begins with a single step".

One more pointon on a prescriptive flooding of L Eyre:

The concept of utilising the dry salt lakes of Sth Australia as a Thermodynamic traffic cop to direct coastal precipitation bands deep into the eastern states on a far more regular basis, is an entirely new mode of thinking.

Previous historical contemplations of flooding L Eyre were soley to do with Sth Australian agriculture and in particular sheep grazing.
The limited scope of these contemplations was the reason they never came to fruition. The cost/benefit ratios were not worth the risk.

The thermodynamic analysis I have initiated plus modern materials technology, reduces risk to an acceptyable level particularly in conjunction with preliminary modelling and a pilot test scheme.

Kaep, if desalinated water is to be introduced to Lake Eyre, I suppose that the salt is going to be dug up and removed.
That will not please the likes of Donald Campbell and Eric Warby in their quests for a place to try for new land speed records.

There must be an error in your calculations, colinsett
Here's how I calculated it.

The area of Lake Eyre is 9500 square kilometers
9500*1000*1000 = 9,500,000,000 square metres
9,500,000,000 * 3 = 2.85*10^10 cubic metres of evaporation per year
(the rate of evaporation from the full lake is actually closer to 2 metres, but lets assume it's 3 m)

So at least that much has to flow through the canal to keep it full.
(2.85*10^10) / 365.25 = 78,028,747.43 cubic metres per day
78,028,747.43 / 24 = 3,251,197.81 cubic metres per hour
3,251,197.81 / 60 = 54,186.63 cubic metres per minute
54,186.63 / 60 = 903.11 cubic metres per second

If the canal was 1km wide and 10m deep it's cross sectional area would be 10,000 square metres. Therefore, the rate of water movement through the canal is:
903.11 / 10,000 = 0.0903 metres per second

0.09 metres per second (0.325 km/h) is so slow you might not notice it flowing even if you were standing in it. The canal could be only 100m wide and the rate of flow would still be less than 1 metre per second.

So the idea of flooding Lake Eyre with seawater is not unrealistic. In fact, the ground between Spencer Gulf and Lake Eyre is almost ideal for it. The canal can run through the bed of Lake Torrens, which is only 8 metres above sea level. The canal can be sea level for almost the whole distance, with a weir at the Lake Eyre end to regulate the flow into the lake. The only pumping needed is to pump water back out of Lake Eyre to keep the salt concentration from getting too high.

Using desalinated water is not an option. The cost to desalinate that much sea water would be astronomical. Using sea water will get the job done as far as evaporation & climate change goes. Lake Eyre is naturally a salt water environment anyway, with natural salt concentrations that are many times higher than sea water.

Geek100,

Nice analysis on L Eyre.

I did some calcs on pumping brine out of L Eyre. It appears to be long term unsustainable. But if you don't pump it out, the project only has a 50 year life till the Lake is fully silted up.

I felt that the answer is to use a network of many 1-5 acre engineered wetlands (EWBs) specialised for the dry,hot conditions. This includes the use of shadecloths and multi-tiered vegetation specific to the area to regulate evaporation to optimal levels.
This strategy keeps local stakeholders and greenies happier and opens up some possibilities that are not at first obvious.

* This year should see Eyre flooded from the Nth with fresh water from Cyclone Larry. A pilot patchwork desal EWB setup could investigate the propensity not only to direct precipitation to eastern states but also to attract monsoonal bands closer to Sth Australia. The run off from closer monsoonal activity could hit the Cooper river and keep L. Eyre in fresh water on a more permanent basis. The pilot would determine what level of EWB networking was required to kick start this phenomena. It is important to remember that there is a historical precedence for mechanisms like this when the Lake was the centre of a burgeoning Great Artesian Basin.

* The desal required for such a pilot would still need a large volume rate of water. But the heat over L Torrens is a bonus because special black sheet evaporation infrastructure there could produce the fresh water required relatively cheaply, pipe it on its way downhill to L Eyre, and pump brine a lesser distance back to Pt Augusta. Additionally, this desal evaporation process itself will be a significant thermodynamic cooling for Sth Australia.

Again I estimate a pilot-study would cost around $100 million and if it turns up positive results a serious-infrastructure will cost around $800 million. The agri Benefit to eastern states could be up to $3 billion per year, at least equal to that of the Snowy scheme along the Murray which is essentially a natural-solar-desal-operation over-a-similar-land-area.

Reading this simplistic math is a real fun as calculations reflected primitive non-engineering approach of amateurs being eventually employed by similar mates of their at appropriate well-paid positions.

However, even Australian-educated so-called professionals, recently graduated especially, too often do not know elementary water/sanitation engineering patterns used round a globe routinely but play computers.

That is why overseas-qualified recognized members of the Institution of Engineers Australia might predominantly dream only of being employed locally if they are non-Anglo-Celts particularly.

Speechifying of ungrateful migrants not happy gardening and cleaning toilets in Australia is common in this forum.