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dzcook
5th February 2009, 02:36 PM
ok here i am in nth qld
At monent there is 4 metres of water over the bridge here ( the bridge is 15 mt approx from the river bed and is approx 1 k long ) so nearly 20 mt of water going down the river to the burdekin dam with an overflow of 6 mt at the dam spillway so i ask why arent they channelling this water back inland to eventually hit the poor murry
they what some big projects to start things off in this recession why not this one
i mean if the ancient romans could move water hundreds of miles why cant we ?
cant we just canel it down through the valleys and small creeks etc that flow that way with the odd tunnel perhaps as well
i know i am making it simple but wouldnt it benefit the whole country if we did ?

RETIRED
5th February 2009, 04:15 PM
Ahhhhh. Dam the Burdekin and send the water back.

When I lived up there in 1972 they were talking about it then as well and had been for 50years before that.

Gingermick
5th February 2009, 07:35 PM
you'd have to lift the water an enormous amount and that would take an equally enormous amount of energy.

Cruzi
5th February 2009, 07:50 PM
Water from Northern Queensland feeds the Channel country and ends up in Lake Ayre.

Channel country is something to behold at least once in your life.

echnidna
5th February 2009, 08:31 PM
so is the lake when its full.

RETIRED
5th February 2009, 08:46 PM
Ditto to both.

jmk89
5th February 2009, 09:03 PM
you'd have to lift the water an enormous amount and that would take an equally enormous amount of energy.

That has been the conventional criticism of the Bradfield scheme ( the same guy came up with it as was responsible for the Sydney Harbour Bridge and designing the Sydney City Circle railway - in any event, he was a damn good engineer with just enough madness to be able to think away the opposing arguments).

It was also the basis on which people said that the Snowy scheme would not work.

The answer is the same in each case - tunnel through, or canal around, any mountain you would otherwise have to pump the water over. Another aspect is to use the head of water created by the dam to raise the water far enough to overcome any level differences. Not sure that is a full answer, but I am told by senior engineers at both Water authorities and universities that Bradfield can be made to work without needing to use any power other than some hydro generated within the scheme.

echnidna
5th February 2009, 09:16 PM
Given that climate change predictions are for much higher future rainfall in the north it may end up being worthwhile both as a flood reduction system and a solution to the low water in the Murray Darling system.

RufflyRustic
6th February 2009, 09:31 AM
I wish they would do something. North QLD is in flood, but our 3 local dams are still hovering around the 10-12% full mark:(

malb
7th February 2009, 07:26 PM
I am not sure of the geography, but to make it work there would need to be a good set of mountains in the area getting the rain that could have their valleys dammed to store the water as it arrived, so that it could be released slowly into channels etc for subsequent use. Might also be more usefull to use the water within say a 500km radius than try to feed it accross two states to minimise evaporative losses.

Reports on Australia All Over last week indicated that both the main river down to Lake Ayre and the secondary (rarely wet, let alone flooded) was running Km's wide, so immediate diversion via that route may not be well received.

Bradfield also proposed building a sea channel into to the inland to flood low lying areas around Lake Ayre, creating a micro climate and ensuring plentifull rainfall into the Murray Darling basin. This probably has a better chance of success for this area.

Gingermick
9th February 2009, 06:24 PM
The answer is the same in each case - tunnel through, or canal around,.

But you'd be lifting water hundreds if not thousands of metres. I couldn't find much online about the burdekin spillway RL.


Not sure that is a full answer, but I am told by senior engineers at both Water authorities and universities that Bradfield can be made to work without needing to use any power other than some hydro generated within the scheme.

That sounds like it would fail thermodynamically. (You cant generate enough power to lift water the distance it fell using the energy of the water itself. )

Skew ChiDAMN!!
9th February 2009, 08:26 PM
That sounds like it would fail thermodynamically. (You cant generate enough power to lift water the distance it fell using the energy of the water itself. )

Not quite. You can't generate enough power to lift all of the water... ... the same height as the distance it fell...

You can lift some as high as you want or all to a partial height.

Gingermick
9th February 2009, 08:38 PM
Very true, but by the time you get to the end, you run out of water if you have to lift it from it original height.
The only solution is to use less water. Particularly Brisbane.....

dzcook
11th February 2009, 10:44 AM
last night on the news they said that the dam at the burdikin was 160 % full the whole of the top of the dam wall is acting as spillway and something like a sydney harbour full of water every hr or so ( or less ) is going over the spillway what a waste
farmers downstream arer complainng that there is to much coming downstream for them to use

AlexS
11th February 2009, 02:02 PM
Water that flows to sea is not wasted. The sole purpose of water is not to provide a means of irrigation - in fact, very few large scale irrigation systems have lasted 200 years, and in Australia, the large irrigation systems are already showing symptoms of dying, such as salinisation.

If you divert much of the water that flows to the sea, you can say goodbye to the east coast fishing industries. The beaches will recede, as many are already doing.
If you like the idea of diverting Queensland water to the Murray, how many irrigators do you think will let a nice big flow like that go past their farm without grabbing a part of it (to say nothing of what will be lost to evaporation)?
Perhaps you could put it in a pipe. That would be a huge pipe that would be empty most of the time, but would require maintenance all the time.

The alternative is to recognise that we live in a place that has extremes of climate, and live with it. Grow crops that don't need a heap of water, use less water on the garden and in your home and don't build on floodplains.

And remember Munroe's law - if a place has had a flood, it will have a bigger one.