Climate change in Western Australia

How Australia's Perth is battling a water crisis

On the south-western coast of the world's driest inhabited continent sits a green, vibrant city that is defying a chronic lack of rain and warming temperatures.

BBC,

16 June, 2014

Perth is Australia's driest major city, yet in its central areas at least, does not feel like a place that has confronted a water crisis. From its perch on Mount Eliza, Kings Park peers majestically over skyscrapers and office blocks, offering lush oases for weary workers and visitors, along with some of the most perfect grass your correspondent has ever seen.

The park with its grand avenues, memorials and statues has become a symbol of Perth's resourcefulness in the face of monumental environmental challenges.

Between 1990 to 1999, the average annual rainfall in the Western Australian state capital was 766mm. Since 2009, that figure has fallen to 656mm.

"Western Australia has seen climate change happen faster and earlier than almost anywhere else on the planet. In the last 15 years the water from rain into our dams has dropped to one-sixth of what it used to be before that," said Sue Murphy, chief executive of the Western Australia Water Corporation.

"We've pretty much lost the capital of Western Australia Perth's water supply and so in the last 15 years we've had to rebuild that supply."

'Climate independence'

For a city touched by the Indian Ocean, it has not had to look far for part of the solution. Two large water factories or desalination plants that turn the sea into potable supplies, have been built. Perth can now get half of its drinking water from the ocean, although conservationists worry that the process is expensive and energy hungry. There has been a hefty price for the community, with household bills doubling in recent years.

While stripping salt from seawater has helped to insulate a growing population against the effects of a drying climate, authorities have been experimenting with the Gnangara system, Perth's largest source of groundwater.

A decade-long trial of injecting treated wastewater into deep aquifers up to 1,000m underground has recently ended. The recycled supplies have been flushed into sandy soil, which acts as a natural filtration process, before clean water is extracted for drinking and irrigation.

The Australian city of Perth has managed to overcome environmental challenges

"The groundwater replenishment trial was highly successful and is now in production," said Greg Claydon, the executive director of Science and Planning at the Department of Water.

"The project… is a highly innovative, sensible approach to the sustainable management of the use of the Gnangara groundwater resource. The green light to progress to seven billion litres a year last year is part of the state's climate independence plan."

Most Western Australians see water for what it is - scarce, valuable and not to be wasted. The old British habit of brushing teeth with the taps in full flow would not be tolerated in these parched parts.

Over the past decade, Perth's population has grown by more than a third, yet last year demand for water was down by 8% compared with 2003.

'Drying climate'

Water-saving tips are now common topics of conversation around the office water cooler.

The state government says a dramatic drop in per capita water use, along with alternative sources have helped Perth, which is home to about two million people, beat the Big Dry.

"In a drying climate we need to become less reliant on rainfall, which is why we go down the path of desalination, around waste water treatment and reuse [and] re-injection into our aquifers," said Mia Davies, Western Australia's minister for Water and Forestry.

On another cloudless day in the west, we meet Rachel Siewert, an Australian Greens senator, at her suburban home 20km from the centre of Perth. Here many lawns and grass verges are in good health, although the local park is brown and thirsty.

While concerned about the costs of desalination plants, Ms Siewert believes Western Australia's water policies are headed in the right direction.

"They certainly are ahead of the other [Australian] states in terms of the fact that they are much more upfront in acknowledging that we had a decrease in rainfall… but we do need to be looking at how we get water in a less energy intensive way and also making sure that we are not further damaging our environment," she said.

Records show that the region began to get drier in the mid-1970s, but officials, who expect those trends to continue, remain bullish about taking on whatever nature has in store.

"We can cope whatever happens to our climate," insisted Western Australia's Water Corp chief Sue Murphy.

Other rain-deprived cities are learning from Perth, which receives a steady stream of visitors from overseas to hear of a city's efforts to become drought-proof.