Dash to save drinking water (from contamination by bushfires)

[depakid]

Bushfires around Maroondah Dam, Healesville, last week.
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MORE than a billion litres of drinking water — enough to supply Melbourne's entire daily water consumption — was rushed out of one of the city's major dams yesterday in a bid to avoid contamination from bushfires.

Despite being confident that Melbourne's biggest dams were not under immediate threat, water officials yesterday continued a massive relocation of the city's drinking supplies. Statistics show that 1.314 billion litres were removed from Upper Yarra Reservoir in the 24 hours to 8am yesterday. A similar mass relocation was expected to be reported to 8am today, with almost all the water being shifted to Cardinia Reservoir.

Melbourne typically uses about 1 billion litres each day. It is believed close to 6 billion litres have been moved since the fires began just over a week ago. Upper Yarra is considered to be Melbourne's second most important reservoir, behind Thomson Dam.

About 2 per cent of the Upper Yarra catchment has burned, meaning any contamination of water supplies is expected to be kept to a minimum. Other dams have not been so lucky; significant proportions of the forest surrounding O'Shannassy and Maroondah dams have burned, meaning that rainfall in coming weeks would wash large amounts of ash and contaminants into the water.

Melbourne Water managing director Rob Skinner has confirmed he may temporarily decommission Maroondah and any other affected dam, if contamination is as bad as feared.

More: http://www.theage.com.au/national/dash-to-save-drinking-water-20090216-899t.html