Parts of Waikato are having to restrict how much water they use due to the hotter weather.

Hamilton, Waipa and Waikato district are only permitted to use sprinklers for four hours a day after consumption jumped up to 20 per cent.

Sprinklers are now only permitted to be used between 6am to 8am and 6pm to 8pm, while hand-held hoses can be used any time.

The three councils run a Smart Water alert system with 1 being the most minor measures and 4 the most drastic, and bans any use of outside water systems.

Advertisement

Smart Water co-ordinator Sally Fraser said the increase is due to pools being filled up and sprinklers being turned on.

Fraser said making small changes to how people used water could make a big difference.

"We can't control the rain but what we can control is how much water we all use," she said.

"Making small changes to your water use will make a difference.

"Having a shorter shower, mulching your vege patch and garden beds and making the most of water that would normally go down the drain to feed your plants, it all adds up."

Hamilton's water consumption had increased by 20 per cent, Waikato saw an increase of 6 million litres of water and Waipa's water use increased from 173 to 190 million litres.