Dry weather and drinking water

Find out how dry weather can impact drinking water, and what you can do to get ready for dry weather.

Summer brings warm, dry weather and the potential for drought.

Droughts happen when a lack of rain, over a long time, makes the ground dry up. This impacts te taiao (the environment) and can:

  • reduce the amount of water in rivers, streams, lakes, and reservoirs
  • lead to restrictions on the water you can use outdoors for gardening and other uses
  • lead to drinking water shortages
  • in some cases, impact the quality or appearance of drinking water.

Are you a drinking water supplier? Read information for you about preparing for dry weather.

Dry weather forecast

Summer 2023 to late Autumn 2024: NIWA forecasts dry weather in some areas

In September 2023, NIWA announced that an El Niño weather pattern will start influencing weather across Aotearoa New Zealand.

Every El Niño is different. But generally, they tend to bring strong or frequent winds from the west in Summer. They also tend to bring above average temperatures. This can lead to:

  • drier than usual weather in the north and east of the country
  • heavy rain in the western and lower South Island
  • wildfires during prolonged periods of hot, windy weather, which can impact the amount of water available for other uses.

From Summer 2023 to late Autumn 2024, NIWA has forecast an increased risk of dry weather for: Northland, Auckland, Waikato, Bay of Plenty, Tairāwhiti, Hawke’s Bay, Tararua, Wairarapa, Marlborough, and down the east of the South Island.

How you can conserve water year around

Most of us have heard the saying ‘water is life’. When dry weather makes water scarce, it reminds us of just how precious water is.

One great way you can show care for wai (water), and your community, is by conserving water.

This is critical during dry weather and drought. But there are some simple things you can do every day to help make sure water is there when it’s needed – whether you’re at home or out and about.

Check out our top tips for conserving water

During a drought

Your drinking water supplier is generally responsible for:

  • working to prevent disruptions to the water supply
  • putting water restrictions in place to conserve water when needed
  • letting you know when water restrictions are in place
  • providing up-to-date information about any water contamination issues.

By following any restrictions or advisories your drinking water supplier puts in place, and conserving water, you’re helping to ensure we all have a safe supply of drinking water.

Find out more about boil water notices

Possible impacts on drinking water supplies

Water restrictions are not the only impact of drought. When the amount of water available in a drinking water network becomes low, this creates the risk of contaminants getting into the network.

This is because drops in water pressure in the system can act like a vacuum, sucking things into pipes.  We call this ‘backflow’ or ‘infiltration’. If this happens, your supplier could issue safety advice. For example, to boil your water. It’s important that you follow any drinking water advisories issued by your supplier, because they’re designed to protect your health.

Low water levels can also change the way water looks, smells or tastes. But that does not mean that this water is unsafe. If you have questions about the taste, smell or look of your water, please contact your water supplier.

What untreated water can be used for

Untreated rainwater, bore water, and water in rivers or streams may contain germs (like bacteria and viruses) that could make you sick. 

Do not use untreated water for drinking, cooking, brushing your teeth or washing dishes.

However, untreated water can safely be used for:

  • washing clothes
  • washing floors
  • watering plants
  • cleaning cars
  • pouring into toilets to flush.

Find out what to use treated water for during a boil water notice

How to make untreated water safe for drinking

Boiling water is the best way to kill most bugs and germs (like bacteria and viruses). Boiled water should be stored in a clean covered container and used within 24 hours.

Boiling water will not remove chemical contaminants.

Find out how to boil water so it’s safe to drink

How you can get ready for dry weather and drought

  • Find out who supplies your drinking water and how they will tell you about any water restrictions. For most people, your water supplier is your local council.
    • If you’re renting your home and you are not on a local council supply, you may want to check with your landlord.
  • Make sure you have emergency water stored for your household (including pets).
  • Make sure any water you store on your property is topped up before summer and stored safely.
  • If you’re having drinking water delivered to you by a water carrier service (like a tanker or truck) make sure they are registered with us.
  • For those in farming and agricultural industries, follow the Ministry for Primary Industries advice on dealing with drought.
  • If you have a lifestyle block, the Ministry for Primary Industries has advice on preparing for a hot dry summer.

How to safely store emergency supplies of drinking water

Here’s some useful information about how to store emergency drinking water safely in bottles or outdoor tanks: 

More information

Weather and drought information and resources from NIWA

Saving water during a water shortage

Farming and agriculture