A lack of rain could force Sydney’s desalination plant to be switched on for the first time since it was commissioned six years ago.

Warragamba dam was at 93.9 per cent capacity this time a year ago, and now sits just shy of 70 per cent.

Sydney Water’s Peter Hadfield tells Ross Greenwood the desalination plant will be put into action when dam capacity reaches 60 per cent.

“The average dam capacity across Sydney is 66.9 per cent and we lost 0.8 of a per cent across the past week.

“In the last month or so we’ve been averaging a reduction of about 0.5 or 0.7 per cent of dam capacity per week.”

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