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Staying safe in outdoor water in Wales

Wild swimming is swimming, dipping, paddling or playing in outdoor natural waters. 

This might be in rivers, ponds, lakes, reservoirs or in the sea.

Wild swimming is popular. It can help physical and mental health and wellbeing. But, open water can be dangerous – be aware of its risks and follow these tips to help to make it safer.

Wild swimming can also be called open water swimming or dipping – this information covers all of these.

What are the risks associated with wild swimming?

These can include physical hazards and hazards from the quality of the water. 

Physical hazards

The weather, tides, currents and water depth can all change quickly so it is important to be aware of these before you enter the water and when you are in it. Even in summer, the water can be extremely cold, leading to cold-water shock. It may stop you from swimming and may affect your breathing.

You may not be able to see underwater dangers which may hurt you, especially if you dive or jump in. The water may also be used for other activities including sailing, kayaking, jet-skiing, or possibly industrial or farming activity. Check before entering the water.

Sea-life such as jellyfish or weever fish may also be in the water and are best avoided. If you do get stung, most stings are not likely to be serious and can be treated with first aid but sometimes you might need to go to hospital.  

Water quality

Sometimes the water you are in contact with can have bugs in it that may make you ill. These bugs can affect anyone’s health but some people may be more at risk, such as the very young, the elderly, or people with weak immune systems.

Natural Resources Wales and some local authorities regularly check for some bugs that can cause vomiting and diarrhoea at some bathing water sites from May to September. You can find the results of these checks online, along with further information about each site. You may wish to ask the organisers of any open water events or activities about what testing they undertake to help avoid you becoming unwell after taking part.

You may also come across algal blooms in water. Many types of algae can grow in huge numbers, especially in warm sunny weather, and form an algal bloom. Blooms may colour the water or form scum on the surface that may be smelly. There are many types of algae in the UK. These include blue-green algae (cyanobacteria) found in freshwater (e.g. lakes and streams) and marine (sea) algae which include seaweeds and tiny plants.

Whilst most blooms are not harmful, some can contain toxins which can cause itching, hay fever–like symptoms, nausea, and fever. As it is not possible to tell by looking at whether an algal bloom is harmful, it is best to avoid swimming where an algal bloom is present. Look out for signs along the water’s edge that may advise you not to use the water.

To report a bloom visit Natural Resources Wales or call their environmental incident hotline 0300 065 3000 (24 hours).

Other less common water quality hazards include Leptospirosis (Weil’s Disease) – an infection spread in the pee of infected animals; and swimmer’s itch (cercarial dermatitis) – an itchy skin rash caused by an allergic reaction to tiny parasites released by infected snails. This is more common in the summer months.

Ways to reduce the risk

Before you entre the water

  • Check the weather forecast and any other conditions.
  • Check the place that you want to swim is safe from physical hazards – stay away from farming or industrial areas.
  • Check the water quality where possible.
  • Avoid swimming after heavy rainfall as this may make the water quality worse.
  • Avoid swimming where an algal bloom is present.
  • Check for any warning signs about the water and follow the advice given.
  • Cover any cuts and grazes with waterproof plasters
  • Stay out of the water if you have had alcohol or taken drugs
  • Avoid swimming alone – if you have to, make sure you have told someone where you are going.
  • Plan how you will get into and out of water.
  • Don’t jump or dive if you do not know if it is safe.
  • Wear a wetsuit suitable for the water temperature and take plenty of warm clothes (including hat and gloves) for after your swim.
  • Know what to do if you accidentally fall into cold water
  • Know what to do if you are stung by a jelly fish, weever fish or other creatures

When you are in contact with the water

  • Try not to swallow the water as you swim.
  • If you get into trouble in the water, try to relax, stay calm and float to live.
  • Keep a close eye on children, even those who can swim, and stay within arm’s length of them.
  • Be aware of other activities that are going on around you in the water.

After your contact with the water

  • Dress quickly when you finish your swim to get warm. A warm, non-alcoholic drink will also help you warm up.
  • Clean any wounds as soon as possible after leaving the water.
  • In general, whenever you have been contact with the sea, river, lake or any other open water, it is a good idea to wash your hands before eating and to wash your body with clean, fresh water as soon as possible.
  • If you do feel unwell after having contact with water seek medical advice as soon as possible.

Where can I find out more?

Bathing water quality – for information on bathing water quality across Wales

Water Safety Wales – for information on drowning prevention and water safety

RNLI Open Water Swimming Safety Advice and Tips – for information on how to enjoy our coasts safely.

ROSPA – Water safety and drowning