I noticed Andrew Bolt drawing attention to plans by the Victorian Govt to release 10 billion litres of “environmental water”. That’s 10 Giga Litres or GL and at a time the Yarra has flooded of its own accord. Surreal waste.
Here are some ideas of mine for discussion.
[1] For a decade now Australian water supply policy has been steadily taken over by the proponents of more expensive water – including the urban supply utilities, academics and many Govt bureaucrats paying great heed to promoting “water scarcity” which dovetail with environmentalist views. At the same time, water utilities are not noted for reporting their operating statistics in a standard and easily understood format and it is fascinating that in a decade not noted for high rainfall, environmental flow requirements usually end up being exceeded.
[2] A key result has been introduction of seawater desalination for large scale urban supplies.
[3] Amazingly this has been achieved in the face of the existence of readily available natural catchment supplies.
[4] The issue of drought post 2000 – often greatly exaggerated and distorted – usually linked with arm-waving “climate change” doomsterism – misleading publicity on rainfall – all have been skilfully brought into play by the proponents of expensive water.
[5] Green anti-dam dogmas have greatly assisted the process aided and abetted by ever present NIMBYism.
[6] The mainstream media (MSM) in general has provided free publicity for proponents of more expensive water – while utilities and Govts are large advertisers. The MSM has always given an outlet for Green ideas without subjecting them to adequate scrutiny. Overall, GreenLeft MSM bias is a factor in the above mix over the last decade. A miniscule amount of MSM space would be devoted to promoting the notion of Govt water utilities piping dam water to consumers at near cost – and yet that is what most consumers would like to see done if asked.
In a nutshell, we have all been conned into accepting expensive water.
I am interested to hear other views.
Good article.
My group, Kimberley Environmental Horticulture, promotes the damming of water…, starting at the gutters. Our landscapes need to slow the speed at which farms, communities, shire councils, state governments drain our stormwater, whether it be swales, contours, weirs or dams. This allows more water available for an increase in the water table (where required) and increases in water consumption due to the population increase. Of course the reverse may be necessary in some areas where the groundwater is salt affected.
Of course, water authorities need to sell water to make money, the higher the price, the bigger the possible profit.
Andrew Bolt has done an excellent job of bringing Victoria’s water ‘horrors’ to our attention.
I have just put up a page with some data on Environmental Flows and Releases. Trying to get accurate more recent annual numbers from the water utility. I find it stunning that for the Thomson Dam, the largest in Melbourne’s water supply system – EF has averaged 35% of inflows for the years 2002-2008. And for the ACT the EF percentage is a lot higher at over 60% of inflows. Is this just another great Green fraud being laid on society ?
Just saw this great reference to our PM saying – “We simply cannot afford to let precious water go to waste.”
Happening all the time Julia !
Annual EF allowance in drought years may be expressed as a larger percentage of inflow for same but still be less than EFs for good years in actual volume,of course. There is surely careful assessment of what are baseline needs for river health which means that EF releases do not maintain a constant percentage relationship with inflows.
Ten GL extra for the Yarra over a year is not much in the scheme of things ,possibly the cost of a rare ‘good news’ story.
What do you see as the ACTs water/dam options over the next thirty years? What is your best assessment of a size and yield for a dam on the Mitchell for Melbourne?
Following your link to the ACT water info,I notice that for much of May the base flow of the Murrumbidgee below the Molonglo junction was apparently about 1 m3/s,half of which was effluent. At the same time the locals were using over a cubic meter every second.
Environmental flows below Corin Dam are of course collected by Bendora Dam,and below that,by Cotter Dam,less evaporation,so only the Cotter [0.5 m3/s] and Googong [1 m3/s] minimum EF figures are relevant.They are considerably less than below Corin and Bendora. It seems releases below Googong were consistently below minimum target,only relieved by a good rain event in February.Cotter’s EFs were consistently a little above minimum target,with a good rain event in March spilling into the next months.Perhaps that March rain event was conserved for water supply in the Googong catchment while being allowed through to flush the Cotter and (dilute the urban-polluted) Murrumbidgee down to the Molonglo and beyond?
Sorry,my maths is off: the base EF for Cotter dam is 2ML/d,or more like .025m3/s,and for Googong Dam 4ML/d=c.0.05m3/s. Not very substantial.
Kandler.
My case rests on annual numbers published by ACTEW – I am trying to find data for both EF and dam inflows post 2005/2006.
I am not getting into the minutae of guidelines for this or that dam – although I am sure that would all be interesting.
Obviously the existing Cotter Dam is the last chance to save water – next stop Wagga Wagga. The guideline number you quote is only a very small part of what happens to water at the very small, old Cotter Dam which frequently overflows as this ACTEW Dam capacity graphic shows. So you see how excess releases from Corin or Bendora can quickly get downstream of Cotter.
The enlargement of Cotter will certainly address that.
Yes, enlarging the Cotter was a “no brainer” although the Greens opposed it. Amazing the Govt resisted doing it for so long. I predict it will be to a stupid extent “crippled” by a profligate EF regime – fish experiments will be a boom industry.
Part of the issue with Environmental Flow calculations is double counting, particularly in the ACT catchments where (as noted) only water released below Cotter and Googong dams is “lost” to the system. This means that the minitua of the guidelines for each dam are actually important. Water released from Corin dam can simultaneously serve two purposes a) meeting community demand (as water comes from the Bendora dam to Stromlo to be treated) and b) meeting (minimum) environmental flow requirements. Since 2006 and the refurbishment of the Cotter Pump station, the same can be said of water released from Bendora dam.
This also means that assuming “Cotter is at 100% capacity and therefore must be (over) releasing water” may not be the case, as the refurbished pump station allows for water from Cotter (released from Bendora) to be captured.
In the recent and current situtation, I expect that there are also some changes in the operating of the Cotter dam as a result of the construction currently occuring. This may result in greater releases (which count towards Environmental flow requirements) than would have otherwise occured.
Additionally, one of the side projects to the modifications (www.actew.com.au/WaterSecurity/MajorProjects/murrumbidgee_pumping_station.aspx?) allows Murrumbidgee water to be used to make up the environmental flow requirements for the Cotter to Murrumbidgee confluence.
This should minimise the effect of any Environmental flow regime.
But then environmental flow considerations are a side issue in terms of water scarcity pricing where with the stroke of a pen the ACT government can vest or water ownership within themselves and impose an additional price on water above any capital and operating costs incurred by the utility.
Reply to KL, The Cotter “base environmental flow requirement” is 2ML/d with a monthly 4 day 20 ML/d release.
The Googong Dam Release requirement is 4 ML/d. Figures fom latest ACTEW Water and Wastewater Report.
My arithmetic gives me a total “out of system” – “base environmental flow requirement” of 3.15GL per year.
I now have some more detailed numbers from ACTEW and the current situation is one of amazing waste. For the last financial year the total Cotter and Googong releases were 10.89GL – or 3.45 times “base environmental flow requirement”.
How much is due to Cotter construction – that is up to ACTEW to say.
For financial years in this last decade characterised by drought and water restrictions – the total Cotter plus Googong releases were as follows – note EF numbers for earlier in the decade are scaled from diagrams in the three ACTEW Annual Reports for 2004, 2005 and 2006. The numbers can vary widely so I have quoted the variations. Remember that water consumption is running at about 45GL.
First the 2004 Annual Report – Environmental Releases;
2001 – 89GL (no wonder our dams emptied)
2002 – 51GL
2003 – 41GL
2004 – 18GL
Next the 2005 Annual Report – Environmental Releases;
2002 – 42.5GL
2003 – 35.5GL
2004 – 20GL
2005 – 14GL
Next the 2006 Annual Report – Environmental Flows;
2004 – 58gl
2005 – 29gl
2006 – 58gl
Note – I would like an explanation as to why 2004 was originally reported as 18GL but by 2006 the number was amended to 58GL.
From ACTEW spreadsheet – ACT total releases;
2006 – 59.5GL
2007 – 10.16GL
2008 – 6.66GL
2009 – 5.26GL
2010 – 10.89GL
So there has been improvement from the utter profligate waste of earlier years but it is clear that much of our so called water shortage is due to the Govt blindly wasting our water and driving down our dam levels. I wonder what water consumers would think of this if it was explained to them ?
I would agree that a release of 58GL (in say 2006) is excessive (especially as the inflow that year was reportedly only 29GL)!
You will have to ask ACTEW why the original 2004 number was later amended.
I expect that the 3.15GL is a theoretical floor to the release requirements – if say there is an overflow at Cotter Dam (because it rains…) meaning that 80ML that was “released” over two days, it will still be necessary to release for the rest of the month, even if you have already reached the “monthly” calculation of the release. The releases for 2008/2009 of ~6-7 GL are probably closer to the practical minimum.
I’m not saying that environmental flows have no (downward) effect on storage levels, just that the effect is not simple.
I think to make your case you really need to know the quantity of water that was solely released for the environmental flow requirements – eg Water that overflowed Cotter in 2004 when Corin, Bendora and Cotter were not able to be used due to the bushfires shouldn’t be counted as a “profligate waste”. You would also need to consider the feedback – ie. in an alternate reality with no environmental flow requirements, how would this impact on evaporation rates (higher dam levels –> higher area) or on consumption (Delaying the calling of water restrictions by say one month in summer –> additional 50ML/d water use –> 1.5GL a month additional demand (25GL over a year based on previous unrestricted consumption levels)) or on the frequency and duration uncontrolled releases (spills/floods)
I’m not saying that environmental flows have no (downward) effect on storage levels, just that the effect isn’t simple.
BTW I would be interested to hear what your thoughts were on “reasonable” environmental flow requirement (as opposed to a “profligate waste”)
The 2006 29GL inflow was an annual figure – while most ACTEW stats are on a financial year basis – their “annual reporting” period.
I must make a graphic of all available monthly data to show that episode of what I term – “utter profligate waste” – which is the 2006 financial year enviro releases of 59GL.
But even recently excessive releases are made – just in Feb this year Googong released 417ML – compared to guideline 120 – why so high when dam levels are so low ? My graphic will have to wait – I am v busy just now.
Perhaps the evidence points to the guideline EF quantities being too low for river health,therefore what may appear to be relatively extravagant surpassing of guidelines at times is closer to the bare minimum useful to flush the river and deal with nutrient build-up.
Perhaps the ‘extravagance’ of 2006 was quickly tempered by the dire straits of the following years of drought. 6 to 10 GL annually is not a great deal of water for two considerable catchments with increasing human populations. Can you make an argument that subtracting 5GL from this and putting it into the reticulated ledger obviates the need for conservation,cost increases and the like?
Perhaps you need to justify the use of ‘extravagant’, ‘utter profligate waste’ and other very loaded language by discussing environmental needs and flows.
I have replies and further information Kandler – will email you when I next post on this. Too busy now.
Added evening 27 August
Taking a long term view on geological timescales, streamflows can be radically affected by natural events such as – the climate changing (it is never static) and stream capture. This Wikipedia article refers to examples of stream capture from Australia including effects on biota – leading to the distribution of freshwater fish that we know today. No doubt if any of these natural events were to be mimiced by an engineering scheme today – vehment Green objections would be raised. The building of a dam naturally reduces flows downstream but this effect decreases as you go downstream and a larger area of catchment feeds the stream. This slight environmental negative is balanced by the brand new habitat of the dam and the interesting new habit downstream of the dam where a near dry severely underfit stream course changes gradually to one less underfit. If humans want water piped to their houses then a dam is the least impact method to get that water.
Looking at the entire scale of human impacts – environmental flows could be abolished because;
negative effects from dams are insignificant when properly balanced against positives;
once you accept EF’s – that pushes up the capital cost of new dam projects by an appreciable percentage as planners have to build a larger dam to provide for the EF’s;
at the same time our useful investment in pre-existing dams is downgraded;
if water consumers were told of the true magnitude of EF’s at a time their water bills were increasing – many would opt for far less EF’s.
So I say, there is a case to simply abolish EF’s – the world will not end – the environment will not collapse – Greens will whine – but that is what they have always done.
I read where Minister Penny Wong says that a water quota of over 50GL is to be released down the Snowy River. What a colossal waste which will have utterly no measurable lasting effect on the river. Against flows varying with rainfall – only a observant person would even notice the increased flow go past downstream where people are.
“EFs could be abolished because negative effects from dams are insignificant when properly balanced against positives ..”
Well,we can only look at each catchment on its own terms:what tiny distance remains of the Cotter below Cotter Dam may stay healthy enough without EFs,given Paddy’s River kicks something in. But it’s a much-visited rec area,and its health has conspicuous PR value,and more given human waste and nutrients entering those popular pools. Similarly the Queanbeyan joins the Molonglo not far below Googong so one could consider removing EF..but,heavy urbanisation will demand perhaps rather more EF than a dam with a rural catchment below its wall.Relying on stormwater as baseflow means a high nutrient load.,plus solid waste. Still and all,you get a lot of water back by the time you’re past the Molonglo junction.
But I agree that the 50GL/A for the Snowy was a conspicuously political offering,given that would still be little against the scale of the streambed past Dalgety,and certainly the tributary contributions from the McLaughlin and Delegate systems and those downstream are adequate. By the time the Snowy is back in irrigable country it is an ample stream;in fact it is so by the border.
In systems in which water is intercepted and then diverted ex-river for long distances or ex-basin forever some EFmust remain,and we need to simple compare annual extraction from dams with annual EF before we can assess much.