Melbourne’s water supply on verge of “disaster” as population balloons

By Leith van Onselen

Ecologists have today warned that Melbourne’s water supply is at risk due to the “collapse” of state forests caused by logging. From The Guardian:

New research led by Prof David Lindenmayer of ANU, published in PNAS journal on Tuesday, has found the ecosystem has already begun to undergo a “hidden collapse”…

The majority of Melbourne’s water catchments are in mountain ash forests, which are either protected in national parks or in state forests where logging is either allowed or has previously occurred.

If those forests have been damaged or are still growing, Lindenmayer said, they draw 12 megalitres more water per hectare per year than forests that are more than 100 years old.

More than 98% of the mountain ash forest in Victoria is no more than 80 years old, and most of those in key catchment areas are less than 80.

In the Upper Thomson catchment, which feeds Melbourne’s largest water supply dam, the Thomson reservoir, about 61% of the trees have been logged.

“That’s a serious issue because two-thirds of all the rainfall in that catchment falls on one-third of the area and that’s the ash forest … that’s called an own goal,” Lindenmayer said…

“My hope is that at some stage people will wake up and say, ‘Oh my god, that’s the water supply for 4.5 million Melburnians,’” Lindenmayer said. “Is it appropriate to compromise the water supply of soon-to-be Australia’s largest city?”

4.5 million Melbournians? Try 4.9 million currently, with the city’s population projected to balloon to 8 million people mid-century.

Regardless, warnings over insufficient water supply across Australia’s major cities have accumulated recently.

In December, Infrastructure Australia reported that household water bills will double in line with energy bills because of population growth and climate change – hitting more than $2500 a year by 2040 – as supply is augmented through expensive desalination plants.

In February, Dr Jonathan Sobels – a senior research fellow at the University of South Australia and the author of a key 2010 report prepared for the Department of Immigration entitled Long-term physical implications of net overseas migration: Australia in 2050gave a brilliant incisive interview on ABC’s Radio National that among other things warned that Australia’s water security is being placed at risk from endless mass immigration:

…we are coming up towards physical limitations within our physical, built and natural environments that will lead to compromises in the quality of our life…

Not only are the dams not filling, but the ground water supplies are not filling. The only option you have open to you is water efficiency use and whacking up desal plants. But if your population keeps increasing at the rates we have seen in recent times, you won’t be able to afford putting up billion dollar desal plants, which also have their environmental impacts…

And in March, ABC News warned that Australia’s water supplies will be placed under intense pressure as the nation’s population balloons:

Increasing demand for water needs to be addressed…

In Sydney, most of the 725,000 new dwellings that will need to be built by 2036 to keep pace with population growth will be built in the west, according to the Greater Sydney Commission.

The compass direction changes, but the trend is the same for all coastal capital cities: population growth is moving away from the coast and away from desalination plants.

“Water being non-compressible and quite a heavy substance — it’s quite expensive to transport,” said Mr Lovell.

“Even if you’re looking at Sydney on the coast through to Penrith or from Wonthaggi to the north of Melbourne — you’re looking at 80 to 90 kilometres. That’s really expensive, and it’s a really inefficient way to transport water”…

Professor Khan said a whole new set of pipelines would need to be built to get desalinated water west of there, where the population growth will be.

Unfortunately, desalination plants are environmentally destructive and hideously expensive, with costs borne by the incumbent population, as noted by The Conversation:

The desalination plants were expensive to build, consume vast quantities of electricity and are very expensive to run. They remain costly to maintain, even if they do not supply desalinated water. All residents pay higher water rates as a result of their existence.

There is, of course, a cheap solution to ameliorating water pressures – one that requires minimal additional investment, nor expensive technical solutions like desalination plants: cutting immigration back to historical levels:

As noted in the 2010 report prepared for the Department of Immigration, entitled Long-term physical implications of net overseas migration: Australia in 2050:

Decreased urban water supply is a significant environmental constraint exacerbated by higher levels of NOM.  Modelling shows the vulnerability of Sydney, Melbourne, Brisbane and Perth to deficits in water supply…

Only NOM levels of 50,000 pa or less result in Melbourne and Sydney maintaining a small surplus of net surface supply over demand on average out to 2050, assuming current climate conditions persist. Potential options to alleviate water stress at high NOM levels over the longer term may be hard to find.

Clearly, Australia’s mass immigration ‘Big Australia’ policy is a key threat to Australia’s water security. So why exacerbate the problem in the first place, when it can be ameliorated by simply returning Australia’s immigration intake back to the historical average of 70,000 people a year?

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  1. Super Phoenix

    “So why exacerbate the problem in the first place, when it can be ameliorated by simply returning Australia’s immigration intake back to the historical average of 70,000 people a year?”

    It occurred to me that perhaps privatization of water supply is on the card?

    Go long water!!!

    • There are solar powered apparatus for home use which can pull potable water out of the air.
      already in use by the military
      when they take off for civilians, that is another revenue steam for the govt dried up.
      Big changes coming

      • haroldusMEMBER

        actually even desert air has a surprising amount of moisture – there was a western australian guy doing this a few years ago

      • ErmingtonPlumbingMEMBER

        “But the apparatus still requires sufficient humidity in the air, no?”

        Not a problem is Sydney mate,…humid all the Fken time,…hot or cold.

      • Diogenes the CynicMEMBER

        I ran a dehumidifier when living in Asia. The thing was incredible – it needed emptying every day! This was mains powered of course but I can see you could use it for camping situations. It would need to be pretty large scale for Western city households given their enormous water use per capita.

    • The solution is even simpler and involves less effort. After logging the forests, just salt the earth so those damn water-stealing trees (and everything else) can’t grow for a few decades.

      • elasticMEMBER

        Then concrete it over to improve water flow into the reservoirs. And since it’s quality water-views realestate you may as well whack up a few high rises to boot.

    • The desal plant was planned to supply up to 30% of Melbourne’s water at full capacity. However population growth since then is also close to 30%. So you’re probably gonna need another one

  2. With land prices in Melbourne amongst the world’s most expensive, these scientists should be working out how to invent more land, not spreading scare stories about water shortages.

  3. That article is a ridiculous conflation of two separate issues. The “ecosystem collapse” to which he refers is the leadbeaters possum habitat (tree hollows).

    Terrible journalism from the grauniad.

    • Its not very well written but the issues are one and the same. Tree hollows take upwards of 100 years to form so these are the trees that are mature and drawing far less water than younger trees.

      • Screw waiting 100 years.

        Send in some 457s/migrant slaves with holesaws and chisels.

      • surely in these days of 3d printing of wood, we can make a few homes for possums
        could even be a cottage industry??

      • I understand that, however the headline very directly implies a collapse of the water catchment, not the collapse of possum habitat. I don’t support logging in the melbourne water reserved catchment areas, but that is terrible editing to the point of being purposely misleading. If 98% is below the benchmark the collapse has already happened.

      • @Wiley Wolf – they have been making sugar glider proof nesting boxes for the dopey parrots in Tasmania. It is certainly possible. While they are at it, parks can clear out all the gullies full of gorse and blackberries.

      • How lazy are those parrots
        I see they have to be chauffeured by helicopter as well
        Next they will be after a UBI

    • @WW “surely in these days of 3d printing of wood, we can make a few homes for possums
      could even be a cottage industry??”

      Houses for possums could sell for an affordable entry price of $150,000 each. That would give the kids an affordable first investment, which they can then trade up to a sheet-metal construction granny flat, before finally using the equity they have built up to upgradento their own 1-bedroom apartment (in a high rise) when they turn 35 or so.

      • Not sure how possums could earn the price,
        I had a ring tail who used to live in a modified milk crate on my balcony
        Everytime I looked in he was asleep.
        But soon they too will be after a UBI as well.

      • Good point

        Time for some taxation concessions for investors in possum hollows

      • Ronin8317MEMBER

        The possum don’t actually need to earn anything, as long as the banks are willing to lend to the possum, they can buy themselves a house!!

        If they default, the bank will just make them into sausage.

  4. The issue is even worse than this.

    The weather systems which have historically brought most rain to south eastern Australia are being sucked further south and leaving Victoria and even Tasmania drier than they have been in thousands of years.

    With the water around Antarctica warming the difference between the land temperatures and the water temperatures means the katabatic winds in Antarctica are getting stronger (as well as more snow in Antarctica).  These drive the weather for the southern hemisphere, and as they speed up they are having the effects of pulling whole weather systems further south.  In Northern Australia the monsoon is extending further south too.  But in Southern Australia the temperate cold fronts are being pulled further south.  Take a peek at the average rainfall for Perth Sydney and Melbourne over the last 50 years.

    • water is a strategic commodity
      Plenty of people know the massive risk we take by having a single source of water.

      • Several years before the Second World War, a Japanese man and his family rented a house next door to my father in laws family.
        The mans hobbies were fishing and photography. Every weekend he would go to different rivers,dams and lakes that fed Melbourne’s water supply ,and both fish and take many photographs.
        About a year before Japan went to war,he returned to Japan,with his photo collection.
        I think the Japanese were thinking strategically at the time.

    • bolstroodMEMBER

      You have done it this time Gunna.
      Don’t you know that we do not mention Climate Change in this country?
      The Prime minister said so.
      Expect a late night knock on your door.

  5. These are some of the few scientists who have the balls to take on the politico-housing lobby and the self interested business lobby that is destroying our country in the name of a growth growth growth policy via mass immigration.

    This is a disaster in the making. Pelting Morrison, Turnbull, Rudd and Gillard with eggs with hindsight means nothing – we need to do something now. It must be obvious to everyone that our political system is failing to protect our society and environment.

    A few good drought years, poor river flows and a competition for water for hydro electricity and irrigation to feed a growing population and global markets, that our neoliberal mates foam at the mouth about, is a recipe for domestic tragedy on an unprecedented scale.

    Of course we privatised energy and water – what a great idea.

    High energy and high water costs that subsidise industry in the name of ‘growth’ will become normalised. It takes massive energy to run a desalination plant – where is that coming from during a drought? Hydro? Maybe energy released from the bullshit that comes out of Scott Morrison’s mouth?

    The only way to use hydro is to deny natural systems the water flow they require by impounding water. This is already a major issue. With every new person added to the population is becomes a bigger issue.

    If you want an Australian population of 50 million without ripping the guts out of the environment you need a massive investment in alternative energy, covered irrigation distribution networks (evaporation is a bastard), an effective public transport system (i.e. better use of energy etc) and a future-proofed water and food production system. Presently we ‘eat’ fossil fuels – it takes some 100-200 units of energy in the form of fossil fuels to get one unit of food energy out of some mechanised food production system.

    All of these issues governments have avoided. Instead they encourage concrete boxes to be built in major cities fuelled by a legal human livestock project. These people are wilfully ignorant to the consequences.

    If we had fusion energy we’d be fine. We don’t.

    This neglect is palpable and dangerous. We are stuffing a massive amount of people down the end of a very long supply chain for food, water and energy in overcrowded cities.

    Want social unrest? This is the right strategy. You want to stuff Australia’s natural systems? You’ve picked a winner.

    Are you a psychopath who would like to see what global warming + increased bushfire + drought + soil erosion + low river flows + global export of out natural resources will do to this country? Then crack open a tin and sit back – this is out future and it has been brought to us by the people who are supposed to protect our nation. Holy roller Morrison is going to bring on the Aussie apocalypse.

    • The next step will see taxation concessions for carbon mitigation and global warming related geo engineering.

      Ultimately we get temperature ‘futures’ and global air conditioning revolving around demand

  6. Oh well. Bottled water like the rest of the sht bag Asian countries we’re becoming.

  7. A practical experiment.
    Straya is the Worlds driest, inhabited, continent.
    To demonstrate how precious water is: You need:
    A 1 liter bottle of water with a cap (a screw top milk bottle is good.)
    An eye dropper
    A teaspoon
    Process: Fill the bottle to the very top and place the cap
    This represents the amount of all the water on the planet
    Remove the cap and carefully fill the cap with water from the bottle.
    The capful represents the amount of fresh water, on the planet including the icecaps
    With the eye dropper place 1 drop of water from the cap into the treaspoon
    This represents the amount of fresh we humans have at our disposal, to use, for everything.
    Not much is it!
    Now mind you pour the water from the bottle on a plant or something, not down the sink.

  8. HadronCollision

    Just added another 100sqm of rain catching roof into tank.
    Now for another 50,000L of tanks to go with existing 75,000.

    Might be time for folks to bug out of Melbs.

  9. blahhh scientists don’t know nuffin, this Korean lady Dr Jay Song who has lived here for 4 minutes says there is plenty water for millions of people even in the middle of the country so ya just all wrong ok

  10. Dr Jay Song?

    Sounds like you’d have to be a racist if you wanted to dissent with her. After all she has spent her life promoting immigration, open borders and is presently at the Asia Institute at Melbourne Uni where she promotes mass immigration whether Australians want it or not – supported by a salary paid for by the an Australian taxpayer.

    Does anyone who’s lived here for a while get a say and right of reply? Who is Jay Song’s foil Melbourne University? Is anyone allowed to argue with her – that you will pay a salary for? Because you believe in free speech and academic debate don’t you? Just so long as it aligns with your PC agenda.

    Because do we really need anti-democratic Asian values and authoritarian rule by a monied elite to replace Australian democracy? Because this is what is happening via the back door. Take a look at Asian governments and pick which one you’d like to model Australia on.

    Strangely, Jay Song is silent on the racism and refugee disasters overseen by Asian nations. She will not tell you of the class system and stateless people of the region where she comes from. She will not reveal that those high rise towers in the mega cities are built by the second class citizens and untouchables who are exploited and humiliated to a degree that is a regional shame.

    No, she’s a human rights champion that sees Australia as the answer to a problem caused by the values that no one dare speak of. Australians are racist – not the policies that exploit the underclass.

    But one thing we do know is that you can always go and fill up a 44 gallon drum of water at Jay Song’s place during the next drought. Homeless people can camp on her lawn and there will always be an Aussie couch surfer at her joint – which she will feed for free. Jay Song will be the first to share and share alike because she is only too aware of the public funding that provides her platform and the responsibility she will have to take for an insane policy. She’ll come out and shoot a few million dying livestock in the head to help out our farmers too. When the dust blows into our cities Jay Song will delight in her open boarders and also take responsibility for trying to turn Australia into a society like Korea – or Neverland. When the climate grim reaper comes for the rent Jay Song will be happy to pay it…unless, that is, she cries “academic freedom” and it is only then that we all wonder why it was that the ABC and Uni Melb gave self interested and ideological fixated people a platform – while they impugned people like Dick Smith. Because some people have not the slightest concept of the environmental tragedy they are the champions of. The reason being that they have been here for 5 minutes and think that all of us know nothing.


    Dear Melbourne University – may we please have an ‘Australian Institute’? You know, the kind of place that seeks to look after the interests of this nation and the people who pay your bills? Or would that be a racist idea too? Instead do we need to suffer institutes of fake demographers and the self-interested agendas of human rights ideologues in silence – as part of your global vision for Australia where democracy is replaced by elites who are off limits and untouchable?