On a stretch of coastal headland in southern Sydney, a sprawling set of buildings houses one of the world's largest desalination plants. But the 45ha complex remains strangely silent.
The A$2 billion (S$1.97 billion) plant can supply 250 million litres of fresh water a day - about 15 per cent of the city's needs. Yet it has sat idle and not provided a drop of drinking water since 2012.
The state-of-the-art plant took three years to build and is powered by its own purpose-built wind farm, but has become largely irrelevant to Sydney's water supply since its completion in 2010.
Heavy rainfall has left Sydney's dams full to the brim and the main catchment, Warragamba Dam, has even overflowed in recent weeks.
Not surprisingly, the healthy state of the water supply has prompted questions about the need for the desalination plant. To its critics, it stands as a monument to poor public planning. Even when idle, it costs about A$500,000 a day to keep on standby.
PLANT BUILT AS 'INSURANCE'
While the plant has been in shutdown since mid-2012, it is important to note that Sydney does not need to be in prolonged drought for it to begin operating again…The desalination plant is Sydney's insurance policy to ensure there is water available, regardless of rainfall.
NEW SOUTH WALES MINISTER FOR LAND AND WATER, MR NIALL BLAIR, on why the desalination plant was built
Water experts in Australia have criticised the "pre-emptive" decision by the New South Wales government in 2007 to proceed with the plant. At the time, the nation was crippled by a severe drought and dam levels were approaching 30 per cent. But experts say the former Labor government could have drawn up plans for the plant and waited to build it when it became necessary.
An expert on urban water supplies, Associate Professor Damien Giurco, from the Institute for Sustainable Futures at the University of Technology Sydney, said the plant quickly became unnecessary because the drought broke and the public improved its water efficiency. This was partly the result of mandatory water restrictions, including curbs on watering gardens and washing cars.
"We paid a high price for pre-emptively building the desalination plant," Prof Giurco told The Straits Times.
"You could get most of the security benefit by being ready to build - by having the permits ready and being able to construct within two years when it was needed."
The plant was effectively privatised in 2012 and has been leased to private operators for 50 years for A$2.3 billion.
New South Wales Minister for Land and Water, Mr Niall Blair, told The Straits Times: "While the plant has been in shutdown since mid-2012, it is important to note that Sydney does not need to be in prolonged drought for it to begin operating again…
"The desalination plant is Sydney's insurance policy to ensure there is water available, regardless of rainfall."
The plant is due to be restarted - at a cost of A$6 million - if dam levels fall below 70 per cent and will operate until supplies reach 80 per cent. The state's Greens party has described it as a "white elephant" and has urged the government to shut it down altogether.
A water expert at the University of New South Wales, Associate Professor Stuart Khan, said the plant had been a "very poor-value insurance policy".
"The costs are very high relative to the likelihood of needing to use it in the short term," he told The Sydney Morning Herald in April.
"Sydney may need desalination in the much longer term, but to build a plant in 2007 for use in 2027 is a very dumb idea."
But Prof Giurco said Sydney's experience should not discourage other cities from building such plants.
"In the next decade, it is helpful to have a functioning plant ready to build to meet a growing demand from increasing population levels," he said. "We will need one at some stage."