'As good as it gets': Call for caution despite water storage closing on 100%

Auckland's water supply is looking healthy in the leadup to summer, with reservoirs almost completely full.

Watercare head of production Peter Rogers said the city's total water storage was at 99.94 percent, across 10 dams.

"In November about double the normal rain fell in Tāmaki Makaurau so now all of our 10 dams are full, and the Waikato River is flowing at great rates - it's as good as it gets for our key water sources as we head into summer.

"Weather forecasters are predicting a hot summer and relatively normal rainfall, with decent dry spells broken up with a tropical storm from time to time."

He said people should still be mindful of how much water they use.

He said hot summer days can increase water use by 100 million litres, a 25 percent boost compared to an average day in winter.

"This puts pressure on our treatment plants and networks.

"We're not asking people to stop using water outside - just try not to let your hose go wild, and if you are going to fill up a paddling pool, why not pour the water on your garden when you're done."

Using a hose for half an hour in Auckland typically uses about 450 litres and costs about $2, including wastewater charges.

Leaks in both the public water network and private pipes also increase in summer, as the ground dries up, soil retracts from pipes and causes them to crack.

"Our crews will be flat out trying to stay on top of leaks in our public network, so if you do come across what you think might be a water leak, please report it on our website so we can fix it as soon as possible.

"And keep an eye out for potential leaks at home too - even a dripping tap could be wasting more than 30 litres a day."

Rogers said Aucklanders were unlikely to run out of water, but shouldn't take it for granted - and he suggested limiting showers to four minutes.