18 April, 2007

Where The Bloody Hell's Yer Head At?

I love a good solution to a water crisis, I really do. But this isn't it. Look, it was enough of a worry that we are looking at smaller and smaller dam water volumes every year, to the point where we may yet have to forego our great Suburban Icon, the Green Lawn. Politicians and spokespeople for the tourism and hospitality industries quite correctly point out that if we lose the Green City image and acquire a Brown City image, we will lose a significant amount of hospitality-related income. And I agree - that way lies a slow slide into the dustbowl. Less appealing city, less people. Less people, less rates and incomes. Less money, less resources to throw at the water crisis... Repeat until ghost town status is achieved...

So why is Mr Derry's plan not the answer then? After all he's right - the Kimberley has vast reserves of groundwater. Okay then let's examine the alternatives. I have a pretty green bias as most of you will know, and it will show in the following paragraphs.

My favourite plan(s):
Yarragadee aquifer / Collie dam / Desalination.
I recently had occasion to spend an evening at a BBQ with an engineer whop has been involved with establishing whether or not the Yarragadee aquifer would be viable and ecologically sound. His (totally off the record, totally honest - he had no idea I'd blog about it) summary is that the plan calls for 45GL of water to be drawn off the Yarragadee annually, and that this would reduce the amount of overflow from the Yarragadee from somewhere between 200GL and 340GL per annum to 155GL to 295GL - in other words, the aquifer would remain overfull at all times and continue to run off excwess water into the sea.

That kind of makes a hash of all the "ecologically unsound" protests which are being touted as the reason to refuse to do this. Combining this with Mr Derry's plan to blend saltier Collie water would produce a far cheaper source of water for the urban area. That's around 90GL extra water per year, at what turns out ot be the lowest cost, and the lowest impact on the environment. In combination with desalination plant, this can actually make the desal plant idea look good too.

Desal plants.
These are not desirable, not because of direct impact on the environment, but because of the energy bill. Energy bills have to be paid for with greenhouse gas emissions, unless someone can make solar/wind energy do the entire desalination process.

And the local impact? As measured in the fairly enclosed area of Cockburn Sound where our first desal plant has been running at 105% of nameplate capacity (around 155ML per day) for the last two or three months as a shakedown run: The plant returns saline water and the extracted salt back into the sea, and from there it disperses extremely rapidly. The extra salt was undetectable at any point 50m or more from the discharge pipe, that is, within 50m all that extra salt is redistributed by even the feeble currents in the Sound.

So if you combine blended water with desalination, you have three extra sources of water for Perth, the Collie Dam, Yarragadee, and desal water which will ensure that we have a chance of water supply continuing even if some mechanical failure strikes, it will rarely disable all three sources AND the existing dams.

Kimberley Pipeline:
The Kimberley has huge reserves it is true, but the point at which the water is to be taken up, but in reality it has not that much more overflow capacity than the Yarragadee aquifer. The same issues will apply there too - putting them a few thousand kilometres away from Perth doesn't make any difference to that. Yes there may be a few less people to be affected if anything goes wrong, but then where do you draw the line? How many people's votes does it take before you shy away from a plan? Because of course that's what it all boils down to...

But. With that said, we already have a prodigious pipeline carrying water, to Kalgoorlie. We know the technology of pipes works, and hey - will you look at that - we are actually one of the biggest iron ore resources in the world! Our politicians have for decades played vote-pandering with the idea of a smelter to produce iron locally. We don't have any such value-adding because everyone can find reasons not to start doing something productive. In truth, we could have a Government-subsidised smelter in the middle of the state near Karratha or someplace, and manufacture that iron into steel pipes, and then use those steel pipes to bring water down. Right past the plant, so that it can darw process water from the pipeline eventually, and because we're producing it here, the Kimberley Pipeline can suddenly become a cheap alternative.

Once in production, the pipeline will have the least environmental impact, and the dependence on Yarragadee and Collie water can be reduced, and in fact those pipelines can then carry water in the other directions if needed due to further climate drying.

The Derry Tanker Plan:
As I said, environmental footprint is my major concern. Building and operating a fleet of supertankers and coastal loading and unloading facilities is not an environmentally sustainable plan at all, I'm sorry. Come on! Several million tons of fuel oil burned every year just to push a tanker back and forth, and remember that one direction is totally unladen as you can't in all conscience carry anything else in a tanker meant to carry drinking water back up the coast, so that immediately wastes half the fuel, and means that the plan has generated two loads of pollution per tankerload of water we receive.

Building a supertanker costs hundreds of millions and well into the billions, especially since we would need to develop the tankers specifically for carrying potable water and making sure it stays potable all the way down the coast. You conceivably need at least two of them, and probably would need a fleet eventually. You need to set up a water loading and unloading facility and harbout for the tankers. In addition to the energy bill for hauling it and hauling the empty tanker back, you also have an energy bill to load the water, and another to unload it. And I realise Mr Derry is proposing to use oil supertankers but in all seriousness can you imagine the cost of just cleaning those tanks to make the drinking water safe, let alone re-lining them? Have you ever seen or smelled crude oil? Its main component is decomposed dinosaurs and trees, remember....

And there's maintenance. Ships are notoriously hard on maintenance costs, because there's a lot to go wrong. A pipeline, be it from the Yarragadee or the Kimberley, just has pumping stations along the way, and you can power those from wind and solar energy at each station, and if we do the clever thing and make the pipe locally, we have plenty of spares - eventually one could even build a redundant line to use while maintaining existing sections.

I strongly urge every one of you who reads this to consider what we want. We don't want a quick fix, and we definitely don't want to create an environmental disaster. And right now, taking water from aquifers outside our immediate region may seem a radical thing to do, but increasing our consumption of fossil fuels is the best thing to do. There's no point in establishing a new water source if we're going to ignore the reasons why we have a water shortage in the first place, and exacerbate those very causes.

For those of you who question why an ecologically-minded person would countenance a plan to build a smelter - I am also aware of how much more dearly it costs us to mine the ore here, ship it overseas, then ship the finished product back. These things all have an energy cost as well, and it is an energy cost that's more than the cost of smelting and processing locally.

Lastly, I urge everyone who reads this article to start thinking not about the dollar cost of solutions, but the energy/pollution costs instead. Once you start, you'll automatically become more economical...


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