Sydney Turns to Desalinated Water as Drought Drains Reservoirs

Aug. 23, 2005

Sydney, Australia's biggest city, may get a A$2 billion ($1.5 billion) desalination plant as the nation's worst drought in 100 years empties reservoirs.

Warragamba Dam, which supplies 80% of Sydney's water, fell to 37.2% of capacity on Aug. 18 and reached a record low 34.8% June 23. To save water, the city's 4.2 million residents have been restricted to watering their gardens just two days a week and banned from hosing down their cars.

Sydney has less than two years of ``poor quality'' water left, said John Archer, who has written six books on Australia's water supply. ``If the desalination doesn't work, Sydney doesn't have any options other than evacuation,'' he said in an interview.

The plan was announced by former New South Wales state premier Bob Carr during a July visit to the desert state of Abu Dhabi. It faces opposition from environmentalists and some residents of Kurnell, the south Sydney suburb chosen as the site of the plant. They say it will use too much energy, is less efficient than recycling waste water and will damage marine life.

``It's not the most astute way to deal with water resources,'' said Greg Leslie, an associate professor at the University of New South Wales in Sydney. ``To be too dependent on desalination doesn't make for a sustainable system in the long term because we're using so much energy to make that water.''

The plant would process 500 million liters of seawater a day. Carr, who retired Aug. 2 after more than 10 years as the state's leader, said desalination is the government's preferred option. Researchers found people were reluctant to drink recycled waste water. Carr's successor, Morris Iemma, last week confirmed the desalination plant, which may take more than two years to build, would go ahead.

Sydney Water Corp., the government agency that manages the water supply, says a ``major public education'' program would be needed to convince people recycled water is safe to drink.

About 68% of residents surveyed are ``uncomfortable'' with drinking recycled waste water, according to a survey by UMR Research Pty. The July survey of 600 people had a margin of error of 4%.

The government's only short-term option for recycling water is to pump treated sewage into Warragamba Dam, which would ``cost 50% more than desalinated water,'' said Frank Sartor, the state's planning minister.

Sydney's water supply will fall short of demand because of population growth, drought, climate change and the unhealthy state of rivers that feed the city's dams, a government study said.

``Sydney's water supplies are increasingly inadequate to meet long-term demand,'' the May 5 report said. The government estimates the city's population will rise to 4.9 million by 2021.

The proposed site for the desalination plant is near to where Captain James Cook landed in 1770 and claimed Australia as British territory. Kurnell is also home to Caltex Australia Ltd.'s oil refinery, a sewage treatment plant and a sand mine.

``This is just being dumped on Kurnell without any discussion and any consideration,'' Kevin Schreiber, the mayor of Sutherland Shire, which includes Kurnell, said in a July 29 interview. ``Residents are very, very concerned.''

Rainfall last month was between 40% and 70% of the monthly average for southeastern Australia, the Bureau of Meteorology said.

To save water, the state government has imposed restrictions on residents. People can hose their lawns and gardens only before 10 a.m. and after 4 p.m. on Wednesdays and Sundays, and can't use a hose to wash their car. Permits are needed to fill swimming pools larger than 10,000 liters (2,640 gallons).

Water use by residents has dropped 12% below the 10- year average since restrictions began in October 2003, when the city's dams fell below 60 percent of capacity, Sydney Water said. People are encouraged to report neighbors who have breached restrictions and Sydney Water officers patrol suburban streets issuing on-the-spot fines of A$220 to offenders.

Mandatory water restrictions were last enforced in November 1994 and remained in place until October 1996.

Source: AP

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