Australian Financial Review
Thursday 26/10/2006, Page: 16
Western Australia has a right to feel smug about its groundbreaking water-supply efforts.
Damned for decades as one of the driest capital cities in Australia, Perth is today basking in its status of being near drought-proof thanks to a $1 billion "water safety net".
While other mainland cities scramble to bolster shrinking water supplies, there is a smugness in the west which will reach new heights early next month when one of the world's biggest desalination plants is switched on.
Built at a cost of $400 million, the 45 billion-litre-a-year seawater processing facility located at Kwinana, about 50 kilometres south of Perth, will account for an estimated 17 per cent of the city's annual water needs. It is part of a threepronged strategy aimed at ensuring that water restrictions, which are constraining residents in other parts of the country, are eliminated from life in Perth.
"It means that we'll get nothing worse than the current restrictions, which is two sprinkling days a week," The Water Corporation chief executive Jim Gill says.
"That's managed to keep Perth and the south of the state green and we'll get nothing worse than that." As well as investing in the biggest desalination plant in the southern hemisphere, Gill's department is planning a $617 million water boring and piping exercise to extract another 45 billion litres of water a year from one of the world's great underground aquifers. In addition, it will launch a water-trading operation with south-west irrigation operator Harvey Water.
Combined, the three new water sources will add an estimated 107 billion litres a year to Perth's water supply, which was once based on a series of dams in the hills to the east and south but which is increasingly reliant on alternative sources. That change is a direct result of drier winters, and the fact that the dam system is only 32 per cent full, close to a record low.
The underground-water tapping plan is based on a deep geological rock trap known as the Yarragadee Formation. It is being designed as a major expansion of an existing borewater supply, but is yet to be approved by the West Australian government's environmental agency.
If it is rejected, plans are already being drawn up for a second desalination plant. "The [second desalination] project is considered a contingency plan for our preferred south-west Yarragadee aquifer option," Gill said in last month's annual report of The Water Corporation.
There is no doubt Perth's first desalination plant will garner significant interest, largely because of the way it has chosen to address the thorny issue of using energy to extract salt from sea water.
Rather than simply book the Kwinana plant up to the state power grid, the giant reverse-osmosis plant (which involves pushing seawater through a series of fine filters) has a dedicated alternative power supply in the form of a new wind farm being built at Emu Downs, north of Perth.
The wind farm is a nifty retort to environmentalists who question the green qualities of desalination and its big energy requirement. But while the uniquely efficient combination of wind and water will have the West Australian Premier, Alan Carpenter, crowing loudly, his next job is to decide whether to double-up by building a second desalination plant or to approve the Yarragadee project.
For Perth residents worried mainly about a regular supply of drinking water, plus having enough left over to keep their gardens green, the choice of desalination or aquifer is not a political hot potato.
Carpenter is yet to reveal his hand, but close observers of the government believe the preference will be for the Yarragadee project, simply because it adds another layer of drought-proofing protection. A second desalination plant will only follow after the first has proved itself to be reliable and cost-efficient.
Moving early on a variety of water sources is a direct result of Perth's traditional water shortage, and a heated political debate which claimed the career of former opposition leader Colin Barnett at last year's state election.
It was Barnett who championed a 3000 kilometre canal from Western Australia's water-rich Kimberley region to the drier, and more heavily populated, south-west. A lack of detailed costing, and questions over the engineering and design requirements, turned the canal proposal into a liability. However, it did serve to make water a high priority on the political agenda - and there it remains.
Last month, Gill returned water to the political centre stage when he suggested that the Kwinana desalination plant could be sold as part of a process of drawing private operators into Perth's water supply system.
"We would take a very open attitude to admitting the private sector to ownership and operation of water sources in the future," Gill said.
Within hours that proposal had been stomped on by Gill's government masters who dismissed the privatisation proposal. Water Resources Minister John Kobelke said Gill's comments were wrong and The Water Corporation's assets were not for sale.
But Gill's failing is widely seen as one of timing. The West Australian government has just completed the dismemberment of its electricity agency, Western Power, and is not yet ready to address the question of private participation in the water industry. When it is, there will be a surprising number of possibilities in a part of the country once criticised for its poor system of water supply.
Early adoption of the desalination option means that a second seawater treatment plant will face fewer political hurdles. Tapping the Yarragadee, which contains a massive 1,200,000 gigalitres of water and recharges at a rate of 374 gigalitres a year (compared with the first stage plan to take just 45 million gigalitres a year), will make expanded extraction easier in the future.
If all that fails, there might even be a return to "Colin's Canal", as the Kimberley proposal was dubbed in the heat of an election campaign. It remains a potential future water supply in the long-term drought proofing of Perth.
0 comments:
Post a Comment