The greater Sydney dam levels are currently at just over 46 per cent and are expected to drop to 45 per cent by next month.
While typically Level 2 restrictions would only be introduced when dams drop to 40 per cent, Premier Gladys Berejiklian says given the lack of rain and a hot summer predicted, they are necessary sooner.
If the drought continues and there is no rain, Mr Hadfield says new restrictions will have to be set based on the conditions.
He's urging people to be sparing in their water use, not just outdoors but inside the home as well.
About three-quarters of all the residential use of water is indoors so there is a lot that people can do. Make sure your dishwasher or washing machine is fully loaded before you turn it on, make sure you fix any leaks around your house and again the biggest one, and it is an easy one to do, is just try and limit your showers. We are recommending if people can cut their shower time by about a minute that'll save about nine-litres of water and that might not sound a lot for individuals, but if the five-million people across Sydney did that, that'd be a 45-million-litres of water saved every day.
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