Recreational water safety

Activities in the sea, rivers and lakes are great fun, but these waterways can impact health if they become contaminated.

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Keeping tamariki (children) safe

Always supervise tamariki near water.

Supervision of tamariki in, on or near water is essential for their safety. Proper supervision in and around water requires a responsible adult keeping tamariki in their care within sight and within reach at all times.

Before you get in the water

Swimming is healthy and fun, and swimming pools are safe and healthy environments. But there are bacteria and hazards that can be present in some of our recreational water spots.

Help yourself and others to stay healthy in and out of the water by following a few simple steps.

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  • If you, or your tamariki, have had runny poos (diarrhoea) in the last 2 weeks do not go into the water.
  • Take tamariki to the toilet before they swim and wash hands after going to the toilet.
  • Where possible, shower yourself and your tamariki before you put togs on. Use soap and warm water (especially in the area around your bottom).
  • Tamarki should wear approved swimming nappies. Cloth and disposable nappies are not allowed at swimming pools. Pool staff can tell you if your nappies are approved.
  • Remember to wash your hands after changing your tamariki.
  • If you think someone has had an accident (you see poo in the pool) tell a lifeguard. They will tell you when you can get back in the water.

Whether you are planning on being in, on or under water, we want you to be safe. With any outdoor activity, conditions can change fast. AdventureSmart has great resources to help you stay safe. They provide people in New Zealand with advice and resources on how to enjoy water activities safely. AdventureSmart resources include the Water Safety Code and the Boating Safety Code.

Water activities — AdventureSmart (external link)

Water Safety Code

The Water Safety Code includes 4 key safety messages:

  1. Be prepared.
  2. Watch out for yourself and others.
  3. Be aware of dangers.
  4. know your limits.

Water Safety Code — Water Safety New Zealand (external link)

Boating Safety Code

The Boating Safety Code has 5 key boating safety messages:

  1. Lifejackets — take and wear lifejackets at all times when you are out on the water.
  2. Skipper responsibility — the skipper is responsible for the safety of everyone on board and for the safe operation of the boat.
  3. Communications — take 2 separate waterproof forms of communication.
  4. Marine weather — check the weather before going out and be prepared for changes.
  5. Avoid alcohol — alcohol affects your judgement and awareness, which are critical for safe boating

Boating Safety Code — Coastguard New Zealand (external link)

The Land, Air, Water Aotearoa website has a tool you can use to check out the water quality test history from sites across Aotearoa New Zealand, including information about:

  • available facilities
  • how to get to there
  • recreational water quality monitoring in New Zealand.

Swimming — Land, Air, Water Aotearoa (external link)

If you are in Auckland or Northland you can also visit Safeswim for information on water quality and swimming conditions at your favourite spots.

Safeswim (external link)

Some regional councils also list water safety information on their websites.

Council websites and maps — Local Government New Zealand (external link)

Algal blooms and cyanobacteria

During the warmer months lakes, rivers and coastal bays can be affected by blooms of algae. Most of these blooms are harmless even if we can see them, but some can be toxic.

Algae and cyanobacteria are an essential part of food webs in aquatic ecosystems. But at times they can also produce biotoxins that pose a health hazard for people and animals in both marine and freshwater environments. 

Both algae and cyanobacteria exist in:

  • planktonic environments (free-floating in water)
  • benthic environments (mat-forming or attached to the substrate of rivers, lakes, estuaries, and other bodies of water).

When potentially hazardous algae or cyanobacteria grow too fast or bloom they are termed harmful algae blooms.

More information is available on the Land, Air, Water Aotearoa website.

Guidelines with information about the risks from algae and cyanobacteria, and advice and guidance for public health officers who investigate suspected cases or outbreaks are available here:

The Environmental Case Management of Persons Exposed to Harmful Algal Bloom and Cyanobacteria: Guidelines for Public Health Officers - Health New Zealand | Te Whatu Ora (external link)

ESR harmful algal bloom study

ESR undertook a field study of harmful algal blooms in Lake Waikare, Waikato, in 2024. The field study looked at the environmental drivers that may influence aerosol (a substance released in a fine mist) production during a cyanobacterial bloom in the lake. Some air samples were also tested to check for cyanotoxins levels in aerosols downwind of a bloom.

No cyanotoxins were found in the air samples, despite the lake having cyanobacteria at levels exceeding the Recreational Cyanobacteria Guidelines.

The study considered potential explanations for this finding.

Environmental health report: harmful algal bloom field study: Lake Waikare 2024 — ESR (external link)

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Blue-green algae (cyanobacteria) are naturally occurring microscopic organisms that live in aquatic environments, such as lakes and rivers. They occur naturally in Aotearoa New Zealand waters. An increasing number of cyanobacterial species are known to include toxin-producing strains.

These natural toxins, known as cyanotoxins, are a threat to people and animals if swallowed or if they come into contact with the skin.

These blooms most commonly occur during spring and summer, and are a natural phenomenon in shallow, productive coasts.

Marine algal blooms are occurrences of rapid and excessive growth of algae in marine environments, such as oceans.

Marine algae are a natural and important part of the marine ecosystem and form the base of marine food webs which other organisms rely upon.

When environmental conditions are suited to marine algal growth, they may sometimes form large blooms. These can cause the water to appear green, orange, red, or form excessive growth of larger macro algae.

Certain algal species may produce toxins which can be harmful when people or animals come into physical contact or eat seafood which have been exposed to these toxins.

Larger blooms can clog fish gills, wash up on beaches, and potentially lead to fish kills through de-oxygenation as the bloom dies off.

If you come into contact with toxic algae or swallow any it can cause:

  • fever
  • headaches and dizziness
  • skin rashes and eye irritations
  • breathing (respiratory) irritations, such as hayfever and asthma
  • damage to the nervous system
  • runny poos (diarrhoea), throwing up, or stomach cramps.

If you feel unwell as a result of contact with toxic algae or an algal bloom, contact your healthcare provider, or Healthline on 0800 611 116

It is best for people and animals to avoid contact with the water if:

  • it looks discoloured
  • has an unusual smell
  • has green or brown particles suspended in it
  • you can see unusual scum or leathery mats of algae on the surface, shoreline, or bottom of the waterway. They may have a moss-like appearance and are usually a greenish dark brown colour.

Your local council issues warnings when toxic algae bloom is found at high levels. However, even if there is no warning or signage you should stay out of the water if it shows signs of algal bloom.

If you are concerned about an algal bloom contact your local council.

Councils in Aotearoa — Local Government New Zealand (external link)

More information about algae is available on the Land, Air, Water Aotearoa website.

When shellfish filter large amounts of some algae they can create toxic chemicals. You may get toxic shellfish poisoning if you eat affected shellfish. This can cause:

  • numbness and tingling around the mouth, face, hands or feet
  • swallowing or breathing difficulties
  • dizziness and headache
  • feeling sick (nausea) and throwing up (vomiting)
  • paralysis or breathing failure in severe cases.

Symptoms usually start within 12 hours of eating contaminated shellfish.

Shellfish biotoxin alerts and more information about shellfish food safety is available on the Ministry for Primary Industries website.

Where is it unsafe to collect shellfish? — Ministry for Primary Industries (external link)

Recreational swimming spots can also be contaminated by animal poo, sewer overflows, and run-off from urban areas. Swimming in contaminated water can cause gastroenteritis illnesses, and skin, ear and eye infections.

To stay safe avoid recreational water or swimming spots:

  • for 48 hours after prolonged or heavy rainfall
  • if farm animals are nearby
  • if there are pipes or culverts running into the waterways
  • where there may be industrial pollution
  • where boats may discharge waste, or in marinas.

Keep your head above water

Most meningitis is caused by bacteria or viruses, but amoebic meningitis is caused by an amoeba that lives in hot pools.

Keeping your head above water in a geothermal pool will protect you from amoebic meningitis.

Keep your head above water — HealthEd (external link)

Amoebic meningitis — Health New Zealand | Te Whatu Ora (external link)

Protocol for clean-up and management of sewage spills to land

The protocol provides guidance for public health officers on the clean-up and management of sewage spills to land at non-workplace environments. 

Sewage spills to land - protocol for cleanup and management — Health New Zealand | Te Whatu Ora [PDF, 255 KB]