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The Grass is Greener in Perth, a Water-Scarce City Adjusting to Climate Change

Photo: Tim Brick of Metropolitan Water District of California visits Perth, Australia water desalination plant
Tim Brick (center) from the Metropolitan Water District of California visits the massive desalination plant recently built to supply Perth, Australia. Photo: ChadBriggs, Flickr with permission

 

The capital of Western Australia, Perth, is at the epicenter of global climate change. The city’s strategic response offers lessons about climate change mitigation, exacerbation and adaptation. The lessons are acutely relevant to the United States, particularly California.

The grass is greener and there’s lots of it in Perth, as residents who once called Great Britain home recreated lush landscapes with sprawling lawns, tidy gardens, and enormous parks. That Great Britain’s climate is cold and wet while Perth’s is hot and arid has not dampened Perth’s love affair with lawns. Nor has the soil, which is as sandy as a Florida beach rather than as loamy as an English countryside.

This fetish for lawns didn’t matter decades ago, when Perth, which is as far from Sydney and Melbourne as Los Angeles is from New York and Washington, was a sleepy backwater with a small population. But the market for resources in Western Australia (led by iron ore, petroleum, gold, and alumina to feed China’s insatiable demand) has spurred population growth. Perth has become Australia’s fourth largest city with 1.7 million people, many of whom “fly in, fly out” to their jobs at mines hours away by jet.

Drawing Down

Finding enough water to support this growth has not been a problem, thanks to ample rainfall and a very large aquifer system, the Gnangara Mound. But the usually predictable trade winds that blow from the west and provide soaking winter storms have been nudged further south and now often bypass Perth. According to the Water Corporation, the region’s major water supplier, surface water runoff to its reservoirs has declined by approximately 70 percent over 35 years.

So the city began to pump groundwater from the Gnangara Mound. The city even encouraged residents to drill their own wells in their backyards.  These bores, as they are called, now number perhaps 170,000, but no one has reliable data on how much water is being pumped. None of the wells have water meters.

Most pumping initially came from shallow aquifers but, as groundwater tables fell and groundwater-dependent ecosystems began to suffer, the Water Corporation began to pump from deeper aquifers. The prevailing wisdom was that the shallow and deep aquifers were not connected. But they are.

In 2012, groundwater accounts for 85 percent of the city’s water supply and the city’s pumping from the Gnangara is exceeding the rate at which Mother Nature is replenishing the supply. So the situation is dire. The supply of water is finite and climate change is threatening the supply; meanwhile, population growth is increasing the demand.

Photo: Perth, Australia skyline and King's Park
A view of Perth across King's Park. The city of 1.7 million faces rising demand for water but decreased rainfall. Photo: eGuide Travel, Flickr Creative Commons

 

A New Direction

In 2006, Perth made a strategic choice to build a desalination plant, powered by a wind farm. The next year the city opted to build a second plant in Binningup, 150 kilometers south of Perth. This second plant will provide 100 billion liters of water every year, enough to satisfy 20 percent of Perth’s needs.

The Water Corporation proudly notes that the Binningup Desalination Plant will rely on solar and wind credits. What is less publicized is that a coal-fired power plant will actually provide the electricity to run the desalination facility.  This irony of using coal, the biggest contributor to greenhouse gas emissions, has not gone unnoticed and the Water Corporation and the Western Australia Department of Water have had to fend off charges of hypocrisy.

Some critics claim that an aquifer south of Perth would have provided an easier and cheaper source of new water, and required much less energy. Other critics argue that reuse of the existing supply was a better option financially and environmentally.

What I find ironic is that, although the Binningup plant will increase CO2 emissions, it made perfect sense to build it – from Perth’s perspective. Climate change scholars have been quarreling the last few years over the wisdom of focusing on mitigating the effects of climate change versus adapting to them. It’s not a debate that I find very interesting: there is no bright line between adaptation and mitigation. The same activity can be both mitigation and adaptation.

Or, in Perth’s case, it’s exacerbation and adaptation. Perth’s use of coal will exacerbate climate change by releasing lots of CO2, but it also adapts to lower river flows and plummeting groundwater tables by finding a new supply of water — the ocean.

Perth will suffer, along with the rest of the world, from the GHGs released by the coal-fired plant. But, the consequence for climate change from the GHGs released by any single plant is trivial. It’s the combination of the small releases by millions of polluters that threatens the planet.

Meanwhile, Perth gets 100 percent of the benefits from running a coal-fired desalination plant: 100 billion liters per year of fresh water.  In this framing, Perth’s decision to use coal is an example of the tragedy of the commons. The air is the common pool resource and the environmental harms are the third-party consequences (or externalities), that is, costs caused by an actor but not paid for (or internalized) by that actor.

The benefits to Perth are direct and immediate (new water) and the harms are diffuse and inter-generational. That’s what makes climate change such an intractable problem.

 

Robert Glennon, author of Unquenchable and Water Follies, is the Morris K. Udall Professor of Law and Public Policy at the University of Arizona. In February and March 2012, he was a visiting professor at the University of Western Australia Law School. Currently, he is on a speaking tour of Australia organized by the National Centre for Groundwater Research & Training (NCGRT) and the National Climate Change Adaptation Research Facility (NCCARF).

Comments

  1. [...] Australia specifically, much of its growth is taking place in western Australia, such as Perth, a water-scarce city, where its underground aquifer is being overpumped due to rising demand. Water conservation and [...]

  2. Mark Tratt
    Perth
    May 2, 2012, 6:45 am

    GHGs released by any single plant is trivial. ??? Really !

  3. John Aguilar
    http://www.globalsiteplans.com/environmental-design/city-of-los-angeles-california-files-lawsuit-for-ownership-of-mammoth-creek/
    April 18, 2012, 10:10 pm

    Wow! A bigger problem disguised as a solution. To solve water depletion, you use a Coal-fueled desalination plant which emit large CO2?

    It only aggravates our problem with climate change.

  4. Water Corporation
    Perth
    April 17, 2012, 2:53 am

    The Water Corporation’s Southern Seawater Desalination Plant (SSDP) at Binningup is one of the most energy efficient desalination plants in the world. The plant does draw electricity from the Western Australian power grid, however, we will purchase electricity from the Mumbida Wind Farm and Greenough River Solar Farm to offset this energy use.

    Obviously, when the wind isn’t blowing and the sun isn’t shining, the plant will draw more energy from the grid than the renewable generators are producing. However, we have ensured that our renewable projects are of sufficient size to cover the annual energy requirements of the SSDP.

    At times we actually generate more renewable power than we need, so over a year as much, if not more, renewable energy is pumped into the grid as is taken out by our desalination plant.

    We are proud of our renewable energy contracts and excited by the prospect of the first utility scale solar farm in Australia starting to produce clean renewable energy in the very near future.

    In our 50 year plan, Water Forever: Towards Climate Resilience, we are working towards providing water to our State in a sustainable way by increasing water recycling, reducing water use and developing new sources.

    We think it also should also be noted that coal generation now makes up less than 50 per cent of grid generation in WA.

    If you would like more information about SSDP, or would like to join our mailing list, please email desalination@watercorporation.com.au

    Peter Huxtable
    Manager Technology and Energy Management
    Water Corporation

  5. Tom Bond
    Bunbury Western Australia
    April 11, 2012, 7:45 pm

    Dont be impressed, the real tragedy is that this drying trend was forecast by climate scientists 40 years ago and widely reported in the papers at that time but was ignored by successive State Governments. No effort was made to curb the excess use of water and even today Perth uses more water per household than any other Australian Capital City. The current prediction is that with GHG emission increasing the rainfall be so low by 2020 no water will be sourced from our numerous dams as the runoff will be so low. All water will be sourced from ground water and desalination. Yet we still dump more waste water in the ocean than is produced by the desalination plants. If the global community adapts to climate change the same as Perth then human civilisation faces a very bleak future.

  6. [...] Water Scarcity National Geographic looks at how Perth, Australia’s fourth largest city, is adjusting to climate change and increased water scarcity. [...]

  7. David Zetland
    April 11, 2012, 8:01 am

    OTOH, it doesn’t make sense to use non-carbon fuels when there’s no global program to reduce it, so leaders in Perth made teh right choice wrt fuel source (not so sure about desal :)

  8. Robert Rhodes
    Baton Rouge, LA, USA
    April 11, 2012, 3:29 am

    I can’t believe Cardinal Pell hasn’t prevented Perth from planning for the worse from a “hoax”.

  9. [...] response offers lessons about climate change mitigation, exacerbation and adaptation. Read more on National Geographic Posted in What Is Climate ChangeTagged change, climate, Latest, [...]

  10. Rhulani Kubayi
    South Africa
    April 10, 2012, 12:07 pm

    I’m impressed with the forward planning in this case. It’s a bit of a downside that the energy required to run the desalination plant is coal-derived. I guess that’s what makes the argument for climate change mitigation hard to sell. If cities from well off countries like Australia resort to taking the easy way out (using energy sources laden with problems), what will convince poorer countries like South Africa (who are stuck with unnemeranle social problems) to adopt much greener solutions? The lesson for the rest of us is that climate change is inevitable. We’re much better off focusing on adaptation measures to deal with the disruptive effects of climate change. Much like the desalination plant example in this article.