NSW Water Minister David Campbell says there is enough renewable electricity to run the proposed desalination plant at Kurnell in Sydney’s south.
Dam levels in Sydney have dropped to 35 per cent and construction of the desalination plant is scheduled to start if levels drop further to 30 per cent.
The trigger point could be reached within eight weeks.
The desalination plant is predicted to use around 225,000 megawatt hours of green energy and Mr Campbell says that will not put a strain on the national grid.
However the Opposition’s water spokesman, Andrew Stoner, says the plant is bad news for Sydney.
"Due to Labor’s failure to plan for Sydney’s water supply needs, dam levels [are] at a record low of 35 per cent and that means we are just weeks away from an energy guzzling desal plant for Sydney," he said.
Meanwhile Greens MP Ian Cohen says level four water restrictions would ban external watering for domestic use and limit water use for some businesses and government agencies.
"We’ve got a Government that’s not prepared to put higher water restrictions on because there is an election coming," he said.
"[The Government] wants to pop a desalination plant to just magically solve the problem a few days out from the election – it is really a porous argument you might say."