Communities are being encouraged to band together and help older people to keep their plants alive when Level 2 water restrictions start on December 10.
Premier Gladys Berejiklian confirmed the tougher water-saving measures, which were due to be introduced in February, would be brought forward.
Level 2 restrictions effectively ban the use of hoses for lawn and garden care and car washing.
Sydney Water advised:
- You can only water your garden before 10am or after 4pm with a watering can or bucket.
- Smart and drip irrigation systems may only be used for 15 minutes before 10am or after 4pm.
- The use of unattended hoses is no longer permitted.
- Hosing of hard surfaces is not permitted, unless in an emergency.
- You can wash your car with a bucket or at a commercial car wash.
- You will need a permit before filling a pool of any size.
Fines of $220 can be imposed for breaking the rules.
Minister for Water Melinda Pavey said not being able to use a hose on gardens "will be a challenge for some people, especially our older population".
"I encourage communities to work together and streets to understand some of those challenges where they might have older residents, to help them keep their plants alive," she said.
"One of the positive things from the Bureau of Meteorology is we are expecting average coastal rains during this summer period, as we go into January.
"That can replenish tanks and keep gardens alive."
Ms Pavey said cautions, rather than fines, had been issued to people found breaching Level 1 restrictions.
"It's really important we take the community with us," she said.
"This is is not about earning fines or earning money.
"We have issued warnings. We don't want to be fining people, we want people to be doing the right thing."
Ms Pavey said 80 litres of water could be saved by avoiding one load of water and household water bills could be cut by $50 by reducing consumption by 10 per cent.
"Take a minute less in the shower and that's 10 litres of water saved," she said.
Ms Berejiklian said the reason for bringing forward Level 2 restrictions was water was flowing from dams faster than it was being replenished.
"Rather than waiting for dam levels to reach 40 per cent [when Level 2 restrictions were due to kick in], we have taken a decision to do it when dam levels reach 45 per cent," she said.
"We anticipate that will happen mid-December, but we have chosen 10 December as the date, so people can be aware.
"Moving to Level 2 in December prolongs us going to Level 3. We will assess conditions as we go along."
Ms Berejiklian said, in the last 12 months, dams had received only 10 per cent of the water they would normally receive.
"If that rate continues, we will have to consider Level 3, but I don't anticipate that's anywhere soon," she said.
Ms Berejiklian said, in 2007, dam levels fell to 34 per cent.
"Currently, we are at 46 per cent," she said.
Ms Berejiklian said the government was still considering the possible expansion of the Kurnell desalination plant.
"We are considering our options in terms of timing [on the announcement of a decision]," she said.
Level 2 water restrictions have been brought forward as a result of poor rainfall and shrinking dam storage.
Premier Gladys Berejiklian is expected to announce on Thursday the new water-saving measures will start on December 10.
They had been expected to start about February when Sydney's combined dam storage level fell to 40 per cent.
It will mean gardens can only be watered by a bucket or watering can during certain times.
Cars can only be washed with a bucket and pools can only be topped up for 15 minutes per day using a hose with a trigger nozzle.
Dam storage for the greater Sydney catchment was at 46.2 per cent on Wednesday.
Ms Berejiklian said a rapid decrease in dam levels had made the higher restrictions more urgent.
"We're experiencing one of the most severe droughts on record and we expect [the] restrictions to save 78.5 gigalitres of water per year," she said.
Level 1 restrictions were introduced in June this year when dam storage reached 53.2 per cent.
Woronora Dam, which supplies water to parts of the Sutherland Shire, Helensburgh and the northern Illawarra, is at 37.4 per cent capacity.
The Illawarra's main water supply, Avon Dam, has fallen to 44 per cent capacity, while Cordeaux Dam is at 38.5 per cent.
The last time Sydney faced Level 2 water restrictions was during the devastating Millenium Drought.
The Sydney Morning Herald reported on Wednesday the latest WaterNSW Greater Sydney Operations Plan showed monthly water usage in Sydney since November last year had been higher than the city's five-year average.
Water Minister Melinda Pavey said the Bureau of Meteorology has predicted another hot summer, worsening the situation further.
The restrictions also affect businesses. "We're doing the work to save as much drinking water as we can to ensure there is enough if the drought persists," Ms Pavey said.
Sydney Water has asked the Independent Pricing Regulatory Tribunal to allow it to increase annual household water bills by an average of $30.