Govt “vandalising” our source of water, claims councillor

By ERWIN CHLANDA

 

The recharge of the Mereenie bore field, from which Alice Springs is getting most of its water, is moving into sharp focus again as Alice Water Smart is looking for ideas about saving the precious fluid.
Councillor Steve Brown, who heads up the council’s environment committee, says the NT Government owned Power Water Corporation (PWC) is “vandalising” the bore field by sustained pumping of too much water.
He says there should be an independent study of how the resource is used, and he is certain that a significant recharge can take place.
He says the second source of water near town, Rocky Hill, should be brought on stream so Mereenie could have a spell, reducing the risk of its sandstone “solidifying” and closing itself off to the underground rivers.
But John Childs, who spent most of his professional life studying water supply in the NT, says Mereenie is “strong, competent and not suffering from compaction issues”.
However, he says the recharge is only about 5% of the current consumption.
“It is perhaps the best deposit of good quality ground water in inland Australia and we are using it in a very casual way, pouring it onto footpaths and lawns,” says Dr Childs.
“We’re lucky to have a very big resource for a very small population.”
He agrees with PWC estimates that the level is dropping a metre a year – 50 metres since being tapped – now 150 metres below the surface.
Cr Brown says PWC’s endemic money problems have forced the Rocky Hill development onto the back burner.
The company is now seeking to cover up its failures by putting its weight behind Alice Water Smart, an unelected body, says Cr Brown.
These moves may “threaten the future of our town, the way we live here.
“Are we not going to be allowed to have a lawn? Step out of our front door onto a sand hill?
“If necessary, let’s find further resources.”
Says the PWC website: “The water that is stored in the [Mereenie] aquifer is very old, dated 10,000 to 32,000 years old.
“This rain fell in a much wetter climate than our current experience, although some rainfall today reaches the aquifer following flows in the Todd River and Roe Creek.
“Mereenie holds vast amounts of water but some of it is salty.
“It is estimated that the aquifer holds five million megalitres of water suitable for drinking, but only 1.25m megalitres of this is high quality (similar to what you drink now).
“One megalitre is about the amount of water in an Olympic-sized swimming pool.”

Image: NT Government.

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5 Comments (starting with the most recent)

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  1. Jane Clark
    Posted November 29, 2012 at 2:02 pm

    @Steve Brown – Thanx for the info about the workings of Mereenie as you understand it. Your explanation certainly appears to make sense. I agree that this needs to be investigated further.

    If there is a technical explanation which refutes what you say, I’d like to hear it or read it. I think we really need to get this story straight.

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  2. Posted November 29, 2012 at 12:02 am

    Thanks for your prompt and rather open response Steve Brown, posted 28/11/12 at 5:58 pm.

    Townsfolk of Alice Springs have every right to be concerned. When Alice had a population of 4000 back in the mid 1960s the town had just emerged from seven years of severe drought; the Mereenie Aquifer was discovered by accident by a team exploring for oil. A timely discovery and I am sure the excitement in the town would have been genuine and justified.

    Alex Nelson covers the detail in his article in the May 14 issue of the Alice Springs News 2009, titled “Gardening in the Centre beyond trial and error – it’s the McEllister legacy”.

    The interface of drought with good fortune in the discovery of Mereenie, to me, is a pretty good evidence of water being our most precious resource.

    However, here we are in a new century with different political priorities and dynamics but really, not much less exciting than 50 years ago.

    An open mind would see that the scenario where the Mereenie Aquifer may not be able to support a much smaller town of Alice at current rates of water usage is a real possibility.

    John Childs gave us a glimpse into the thinking of the government of the day as reported in the October 30, 2008 issue of the Alice Springs News. Sorry John.

    Keiran Finnane wrote under the heading: Water and Dust at Angela Pamela uranium prospect: “First we need the proposal to get the facts.”

    She said: “We asked to speak to the government’s Department of Natural Resources (South), John Childs, to gain greater clarity on some of the persistent questions about the impact of a potential uranium mine on the town’s water supply. No go. Too bad if people are worried.”

    Reading between the lines if I may Steve Brown, it would appear that a lot of the science of the day is rather ordinary, dependent a bit too much on lady luck and certainly not showing too much responsibility for the citizens of the Centre.

    Far too much reliance on self-belief. A new report needs to be commandeered to wipe away the subjectivity of old to enable a sounder scientific base to be established.

    Yes, 100 years is not long in regards to water supplies which are so old.

    May I finish by reiterating the words of Domenico Pecorari when he said on 27/11/12: “Yes, we do need to value our limited water supply more than we do at present, Councillor Brown, to use it only where necessary and to modify our lifestyle to suit our climate, particularly as we advance into an era of climate change. As for your obvious love of lawns … don’t get me started.” (!)

    David Chewings aka THE lone dingo

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  3. Steve Brown
    Posted November 28, 2012 at 5:58 pm

    When the Mereenie Aquifer was first discovered by drillers looking for oil, it was at a time of great upheaval in our town. The town basin was becoming polluted and was no longer large enough to cope. A new supply bore, know as the “St Marys Bore”, was drilled. This bore provided the additional water requirement but also resulted in drying up the local Farm Area bores which in turn lead to the collapse of our quite substantial fruit and horticultural industry.
    There was much discussion and planning for a water supply dam on one of three sites. At five minutes to midnight came the discovery of the Mereenie field, quite by accident. There was great excitement. The Department of Water Resources went to great lengths to educate the entire community on this wonderful bountiful new water supply.
    All the schools toured the drill sites, there were public displays and lectures, experiments in the science labs for students. Everyone was very well acquainted with the operations of our new water supply, a supply we were told of immense proportions, that if looked after carefully should supply the town indefinitely.
    What we learnt from demonstrations and the best available science at the time was that the Mereenie Aquifer consisted of porous sandstone through which the water moved quite slowly, so that when you pumped a particular location over time, that location would draw down deeper and deeper because you were pumping water out at a quicker rate than it could refill through the sandstone.
    The effect of that draw down is twofold: firstly you need more energy to pump the water up and secondly – something about which the Dept of Water Resources went to great lengths to educate us – was that if the area where the sandstone was left dry for too long by the draw down, the sandstone would compress and become solid, thus no longer leaving us with an aquifer that could refill.
    So in the early days of Mereenie it was clearly understood and considered to be of paramount importance that when a particular location was pumped for a set time it would then be then switched off for a set time allowing the aquifer to refill before it could solidify.
    The Mereenie Filed was operated in that fashion for at least the first 20 years of its life. As an electrician I worked for a time on this field helping to install and maintain the pumps and their control systems so I know this to be factual.
    It was always clearly understood that when usage became great enough we would have to develop a new bore field elsewhere in order to allow Mereenie recovery time: therein arose the problem still plaguing us today.
    Moving the field was enormously expensive and a neglectful northern government not wishing to commit funds came up with apparent new engineering advice that said it was quite OK to continue operating to a deeper and deeper level at the original field.
    As this was a vastly cheaper option, that’s the option they took and that’s where we still find ourselves today. Now what deeply concerns me is which is the correct advice? The latter advice curiously coming to light at a time when Government wasn’t willing to commit further development funding? Or is the early science correct. If it is then it is quite possible that we are sabotaging one of the nation’s great assets and our community’s greatest asset, our water supply.
    The so called Water Smart program backed by PAWA and the move to draw up rules about water usage has left me with a nasty suspicion there may be a threat to the longevity of our water supply of which the community is unaware. I think it’s high time we had an independent study done on the operations of this field to allay any fears and to come up with a monitored harvest and operational plan for the field free of agendas, in which the community can place some trust and make sound judgements about the future. When taking into account present talk of privatising PAWA, the body that presently controls and operates this field, this independently monitored plan becomes of paramount importance for our community.

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  4. Posted November 28, 2012 at 1:59 pm

    @Steve Brown. You accuse PWC of vandalising the water source of the town of Alice Springs but reading this article I find it hard to follow just where you are coming from.

    Yesterday you said of our most precious resource, “We have enough water to supply a much larger town…for a couple of hundred years without recharge.” You seem to have a pretty casual and laissez-faire attitude to this resource of ours which in the case of the Mereenie Aquifer is dropping by 1 metre annually.

    As a town leader you must lead the charge in encouraging your citizens to use water responsibly, and not ignore proposed reforms just for the sake of opposing a new idea.

    Just who are the real vandals in terms of water usage? Do the greens of your magnificent golf course still depend on drinking water to maintain pristine condition? Hypothetically speaking, (of course), would not a local government regime that supported uranium mining 23 kilometres from the town of Alice be considered extremely casual to the point of it being environmental vandalism?

    Regards from David Chewings aka THE lone dingo

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  5. Posted November 27, 2012 at 5:26 pm

    Some years ago, an hydraulic engineer told me that, at current rate of use, there was “about a hundred years” left in our underground water supply, news which at the time made me think “Hey, what are we worried about?”
    After a while, I realised that a hundred years isn’t all that long, really, and that the problem is more that the water will become more and more costly to draw up from the aquifer and that the increasingly salty water would need more and more costly treatment to be made drinkable.
    Yes, we DO need to value our limited water supply more than we do at present, Councillor Brown, to use it only where necessary and to modify our lifestyle to suit our climate, particularly as we advance into an era of climate change. As for your obvious love of lawns … don’t get me started.

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