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

  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...

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).

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Meet the Author

Robert Glennon
Robert Glennon is the Morris K. Udall Professor of Law and Public Policy in the Rogers College of Law at the University of Arizona. Glennon is the author of the highly-acclaimed Water Follies: Groundwater Pumping and the Fate of America’s Fresh Waters (Island Press, 2002). His latest book, Unquenchable: America’s Water Crisis and What To Do About It, was published in April 2009. Since then, he has been a guest on The Daily Show with Jon Stewart, The Diane Rehm Show, C-SPAN2’s Book TV, and numerous National Public Radio shows. His other writings include pieces in the Washington Post, the Boston Globe, Bloomberg, the Arizona Republic, and the Arizona Daily Star. He also blogs for the Huffington Post and for National Geographic’s Water Currents. A recipient of two National Science Foundation grants, he serves as Water Policy Advisor to Pima County, Arizona; as a member of American Rivers’ Science and Technical Advisory Committee; and as a commentator and analyst for various television and radio programs. Since 2009, his speaking schedule has taken him to more than 30 states and to Switzerland, Canada, Singapore, Australia, New Zealand, and Saudi Arabia. Glennon received a J.D. from Boston College Law School and an M.A. and Ph.D. in American History from Brandeis University. He is a member of the bars of Arizona and Massachusetts.