If Whangārei residents reduce their water consumption by 20 per cent they might keep the district's water restrictions at bay for a few weeks yet, the council has said.
Whangārei District Council hasn't put restrictions into place yet, because dam levels have been kept more than 70 per cent full by using other water sources.
60 per cent marks the critical point, when restrictions would be required.
"After the 2009/10 drought we installed a much bigger pipe to the Hātea River. As a result of this, and a range of other works, we were able to use the river water and avoid using the dam," the council's water services manager Andrew Venmore said.
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"No rain has come and the Whau Valley Dam is now starting to drop at a rate of about 5 per cent per week. We need to slow that rate of consumption so the supply can last into the wet weather."
He said the outlook for the coming autumn was for dry weather, without any sustained period of rain to top up aquifers, groundwater or the dam – which would require three to four weeks of downpours.
"A bit of rain will let us switch back to the river intake and ease the demand on the dam for a short while, but we want people to cut their daily water use down by about a fifth, voluntarily."
WDC said if everyone in the district reduces their water use voluntarily, council could delay imposing official restrictions.
Venmore said sensible water use would become the "new normal" as Whangārei's climate becomes increasingly dry over the years to come.
Ideas for saving water include:
• Watering the garden by hand.
• Reducing laundry or dishwashing loads.
• Letting the car get dusty.
• Keeping showers to 4min.
• Keeping cold water in the fridge instead of letting tap run until cold.
Venmore said all of those measures made a real difference.
The domestic supply accounts for 70 per cent of the water use in the district every day.
The amount that Whangārei is delivering to the Far North to relieve their water shortage adds up to less than 1 per cent of the district's water use.
"Given the kind of weather we have had this year we are in a very good situation compared to our neighbours, Far North and Kaipara. We will help them if they need water, but we will also need to save water for ourselves."
Visit bewaterwise.org.nz for more information.