Open water safety

Open water swimming means swimming in:

  • the sea
  • rivers and
  • lakes

It can be good for your wellbeing and is getting more popular.

Open water also carries risks. It can increase the risk of illnesses and stomach bugs.

This can cause:

  • diarrhoea
  • vomiting
  • chest, skin, ear and eye infections

Anyone can get ill from swimming in open water but the risk is higher for:

  • children and beginner swimmers because they are more likely to swallow water accidentally
  • those with a weaker immune system
  • those swimming in rivers and the water where a river or stream meets the sea

Heavy rainfall can wash harmful bacteria from farmland, urban areas and sewage to rivers and the sea. This can affect the water quality.

You should not drink open water.

You should wash yourself with clean water and soap after an outdoor swim, especially your hands and any cuts or scrapes.

If you do become ill with any of the above symptoms, call your GP or 111 and tell them you have been open water swimming. Do not swim again until your symptoms have been gone for at least 48 hours. Your doctor might tell you not to swim for even longer.

For more information and top tips on keeping safe, go to .

See water quality and Open Water Quality Position Statement for information on the water quality of our drinking and coastal waters. 

Our staying safe at the coast web page provides guidance around lifeguards and beach safety.