Desalination is suddenly a sweet solution

Weekend Australian
Saturday 23/2/2008 Page: 7

ONCE viewed as an option of last resort, desalination is being hailed as the saviour of Australia's ongoing water crisis. Until last year Australia had no large-scale desalination plants in operation and until very recently the idea of drinking desalinated water was viewed as outlandish, even outrageous. Today, 17 per cent of Perth's drinking water comes from the country's first desalination plant at Kwinana, south of the city - which will rise to more than 30 per cent when a second plant is opened in 2011. State governments are scrambling to jump on the desalination bandwagon.

Plans are in place for five new plants that will supply drinking water for most of Australia's capital cities by 2012. In Perth alone, Water Corporation boss Jim Gill has mooted the idea of building up to six desalination plants along the coast to combat the long-term decline in rainfall. And Queensland is toying with the idea of having two portable desalination facilities on the Brisbane River.

So how did the seismic shift in thinking about desalination come about? Why is desalination - famously described by former NSW Premier Bob Carr as "bottled electricity" - suddenly in vogue from the west coast to the east? The Australian Water Association, which represents water service providers, attributes the popularity of desalination to extreme drought and increasingly sophisticated technology. Deputy executive director Claude Piccinin says desalination has historically been an expensive, energy-intensive process.

"New technology has seen the price come right down, so suddenly it's become much more attractive," he says. "And more fundamentally, the drought we've had over so many consecutive years is like nothing previously experienced, and I think that's what has got desalination across the line." Western Australia's Water Corporation began thinking about desalination on a large scale in 2001 which CEO Jim Gill describes as the "wake-up" year, when rainfall reached record lows and dams were reduced to mud. Realising it could no longer rely on dams and groundwater, the corporation adopted a diversified approach including recycling, water restrictions and ultimately desalination, described by Gill as "the jewel in the diversity crown."

Designed, built and commissioned in less than two years, the plant was officially opened in April last year. Its energy requirements are substantial - 24 megawatts of electricity per annum, or enough to power 30,000 households - but the Water Corp has offset this by purchasing the equivalent amount of renewable energy from a purpose-built wind farm near Cervantes, north of Perth. The 45 gigalitres of water the plant produces each year reaches around 1.6 million people in the south of the state.

Water Corporation spokesman Phil Kneebone says desalination has meant the city's comparatively lenient water restrictions have not needed tightening and has allowed water to be transferred into the state's dams. "We've not had to go further than the two-day a week watering roster and we've been able to bank 10 billion litres of water into the Canning Dam for future use, he says. "This is the real bonus -- the water produced through desalination that is not needed immediately can be transferred elsewhere and called upon during times of heavy demand." Australian Water Association chief executive Tom Mollenkopf believes desalination has saved Perth. "If not for desalination, Perth's viability as a major urban centre would have been in question," he says.

Even the sceptics have been converted by the success of the new plant. Head of the University of Western Australia's Centre for Water Research Jorg Imberger has been a long-term-critic of the plant, but the centre's 2007 report into its environmental impact on Cockburn Sound found marine life had not been adversely affected. "I'm satisfied that the first one is running well and not doing any harm to the environment," Imberger says.

Perth's desalination plant is now viewed as the national blueprint - and Melbourne, Sydney, Adelaide and the Gold Coast have now committed to following WA's lead. Having done an astonishing policy backflip on desalination, the NSW Government is now planning a $1.9 billion facility at Kurnell in the city's south. Using the same reverse-osmosis technology as Perth's plant to remove salt and impurities from seawater, the Kurnell plant will also use renewable energy offsets from up to six wind farms across NSW. Water from the plant will be pumped through a pipeline into Sydney's water distribution system and will ultimately reach up to 1.5 million people.

The Victorian Government, also formerly opposed to desalination, is pushing ahead with plan to build Australia's biggest desalination plant, at Wonthaggi, by the end of 2011. The $3.1 billion project will provide up to a third of Melbourne's water supply and will also provide water to Geelong, Western Port and South Gippsland -150 gigalitres a year in total. It includes an 85km pipeline to connect to Melbourne's water system, and the Government hopes it will put an end to the city's water restrictions.

The Wonthaggi plant will consume around 90 megawatts of electricity per annum, also to be purchased from renewable sources. Detractors claim the greenhouse emissions from the plant will be the equivalent of an extra 240,000 cars on the road. Community concern about its impact on the environment have prompted the government to commission an environmental report, but it has warned the report would be unlikely to stop the plant proceeding.

In Adelaide, work has begun on a $10 million pilot desalination plant, the precursor to a $1.4 billion plant to be built at Port Stanvac that will provide about 25 per cent of the city's water needs. Due for completion by 2012, the plant will supply about 50 gigalitres of water per year with the potential for it to double in size, While the Government is still examining energy supply options, it has commissioned a $3 million environmental baseline report to look at the impact on the. Spencer Gulf marine environment. A second major desalination plant is also under serious consideration to service the Olympic Dam mine, Whyalla and the Eyre Peninsula.

Meanwhile, the Gold Coast's $1.2 billion desalination plant at Tugan is due to be completed by late November. It will supply 120 million litres of water a day. The Government has also mooted the idea of two temporary desalination facilities on the Brisbane River and has been examining options for a second permanent desalination plant north of Brisbane. One report, commissioned by the Government in 2006, recommended building the world's biggest desalination plant - capable of producing a staggering 400 million litres a day to service south-east Queensland.