"That's water that will otherwise go straight down the drain," Ms Robson said.
Watering gardens was best left until the evening when it would have maximum effect, car washing should be delayed, and washers on dripping taps should be replaced.
"If everyone makes an effort, we can protect our water supplies and ensure we can get through the current situation with minimal inconvenience," Ms Robson said.
South Hokianga was the worst-hit area in last summer's big dry. Its two water schemes depend on drought-sensitive sources, the Petaka Stream in Rawene and the Waiotemarama Stream in Opononi-Omapere.
The council has been investigating alternative supplies and the long-term plan includes several of proposals.
The dry weather has already seen fire restrictions put in place across the whole of Northland.