The push to build alternative sources of drinking water in Australia has gained momentum in the wake of a drought that has gripped the country since 2002.
While there is confidence the drought will eventually relent, scientists warn that the arid conditions are a long-term problem for Australia because of climate change. According to CSIRO, Australia's national science body, annual average rainfall is expected to decrease substantially over the next two decades across all of the country save the far north.
Water scarcity has coincided with a population increase of 1.4% per year. The statistics are startling: about 13M people – more than 60% of the country's population – live in areas where water supplies are limited.
Many water companies in Australia have therefore turned to converting sea water to drinking water using desalination. Its popularity as a reliable alternative source of drinking water has led to the equivalent of more than £3.5bn being invested in desalination projects in every major metropolitan area.
60% of the population live in areas of limited water supply
£3.5bn the amount currently being invested in desalination
But desalination has its detractors, not least because of the amount of electricity consumed by the process. In the UK, for instance, London mayor Ken Livingstone has consistently lobbied against the country's first plant being built in Beckton, east London. The desalination plant will be used as a back up in the event of a drought, but Livingstone believes that the environmental and economic case for desalination does not stack up.
Desalination also initially met with opposition in Australia. Some experts even warn that by rushing to find ways to "drought-proof" water supplies, the Australian government may be taking on a huge financial burden unnecessarily.
"It just becomes an economic white elephant," says Stuart White, director of the Institute for Sustainable Futures, University of Technology, Sydney. "If you build them and come out of drought, it's a huge surplus you have to keep paying a premium for over the next 50 years."
Government officials who have backed desalination in Australia say the stakes are simply too high to leave anything to chance.
"It's not been a popular decision everywhere, but it is obviously the right decision to make," says New South Wales water utilities minister Nathan Rees. "If you are presented with all the facts and materials and projections and then choose not to build it, then that would be a seriously irresponsible discharge of government."
a £1.4bn plant is being planned which will supply 150bn litres of water a year to the Melbourne area - about a third of the city's water supply. Construction is scheduled to begin in mid-2009 and will be completed in 2011. The project includes an 85km pipeline to connect the facility to the Melbourne water system.
put the Kwinana Desalination Plant online earlier this year The Water Corporation. Western Australia's water utility, is also considering a new facility in the £390M range. When it is completed in 2011 the Binningup plant will provide 50 gigaliters of water per year and have the capacity to be doubled in size if needed.
is also eyeing a £625M desalination project at Port Stanvac which could be completed as early as 2012. A summary report on the project was completed earlier this month and the next step would be the construction of a £4.5M pilot plant next year. The project would also require the construction of a £136M pipeline to connect two nearby reservoirs.
the £491M Gold Coast Desalination Project is scheduled for completion in November of next year. The plant will provide 125ML of fresh water daily to south east Queensland, which will account for approximately 20% of the area's water needs.
£886M facility underway.
Sydney's desalination plant
'There's no yuk factor with seawater'
Like most other water agencies in Australia, desalination was not Sydney Water's first option for securing the city's water supply. Most urban areas in the country have instituted severe usage restrictions to conserve the resource.
In New South Wales (NSW) water conservation measures are expected to save approximately 145 billion litres of water over the next eight years.
Last September, the NSW government announced the ongoing emergency water restrictions in Sydney would now be permanent.
Sydney Water also examined the possibility of treating effluent for reuse but decided the option was not feasible. A primary problem was the cost of building a plant and more than 80km of pipeline to return the treated water to the city's main supply.
"Even leaving aside the 'yuk' factor Đ and that's significant Đ the price of doing that was about AS$1 billion [Ł446M] more than the construction of a desalination plant," explains New South Wales water utilities minister Nathan Rees.
About 80% of the water supply for New South Wales comes from the man-made Lake Burragorang. The 2006 Metropolitan Water Plan stated that should water levels fall below 30%, a desalination project should be built. The trigger level allowed for enough time to build
the plant Đ about two years Đ before water supplies reached critical if they continued to drop.
Last February, the water levels in Lake Burragorang dropped to 33%, prompting the government to give the project the green light.
Government officials defended the accusations of moving too soon on the fact the amount of water had only been kept at that level by transferring water from other sources.
Another key concern over the plant is its environmental impact due to the large amount of energy the desalination process requires. To handle that, the government has insisted that all of the plant's energy requirements will be supplied by carbon neutral energy, most likely wind power.
But the Sydney plant's projected full-capacity energy requirement of 400,000MWh will absorb a fifth of the wind power available in Australia at the moment. Which means new wind farms are likely to be built to accommodate the plant's needs.
Six wind farm projects in New South Wales have received planning permission, but none have been built yet.
Most of Australia's current desalination projects are slated to be built within a 26-month window to bring the resource on-line before water levels drop to critical levels.
Work on Sydney's £826M desalination plant began last July as soon as the bid was awarded to the Blue Water joint venture. It will have a capacity of 250 megalitres of water a day.
The project also includes the construction of an 18km pipeline to connect the plant to the city's water system.
A consortium consisting of Australian construction firm John Holland and Veolia Water of France won the £428M contract to design, build, operate and maintain the plant at Kurnell on Botany Bay south of Sydney for 20 years.