Parts of NSW are about to face their toughest water restrictions in a decade as the state grapples with one of the most severe droughts on record.

Under the restrictions – last imposed during the millennium drought – residents will be able to water gardens only with buckets or watering cans, and only between approved times.

Cars can be washed only with buckets or taken to commercial car washes. Topping up of pools and spas will be limited to 15 minutes a day with hoses with trigger nozzles.

Premier Gladys Berejiklian and Water Minister Melinda Pavey said on Thursday the tougher regulations, which will apply from December 10, will apply to residents in Sydney, the Blue Mountains and the Illawarra.

With the drought only getting worse, Level 2 restrictions will be in place from 10 December.
Fines will apply, so find out how restrictions apply to you https://t.co/Q8r7vYurfb pic.twitter.com/VX3Wfqmfnb

— Sydney Water (@SydneyWaterNews) November 21, 2019

Level two restrictions are usually enforced when Greater Sydney’s dam levels fall to 40 per cent. But they are being brought forward with total storage sitting at 46 per cent.

Dam levels sink by about 1 percentage point a week, even with the Kurnell desalination plant in full operation. That means they are expected to hit 45 per cent in December.

Sydney’s dams have not been at such low levels since the millennium drought, which ran from 1996 until mid-2010.

“We’re experiencing one of the most severe droughts on record and we expect introducing level two restrictions to save 78.5 gigalitres of water per year,” Ms Berejiklian said.

Level one water restrictions were introduced in June.

Ms Berejiklian said introducing level two rules in December would prolong the period before level three restrictions had to be considered.

Ms Pavey said Sydney water use had dropped from about 200 litres per person per day before level one restrictions were introduced to about 183 litres per person per day in October.

-with AAP