Skip to main content
hpa logo
Topics A-Z:
Search the site:
Home Topics Infectious Diseases Infections A-Z Bathing water and beach risks

Bathing water and beach risks

What are the microbiological risks in the beach environment? 

Beaches are not sterile areas and there will always be some micro-organisms present in the beach environment. This means that there is always a small chance of becoming ill if people come into contact with these organisms. Other risks to beachgoers include the potential for physical harm, such as drowning, or falling from a cliff.

What can affect these risks?

Various factors influence bathing water quality and the beach environment. These include the presence of cattle grazing in the area near the beach, as run-off water can carry pathogens (harmful micro-organisms) from cattle on to the beach via streams running into the sea.

Urban run-off water can increase the number of pathogens on a town beach. These risks are increased during times of heavy rainfall. The risk of acquiring infection and becoming ill as a result may be higher for children and other vulnerable people. Other factors that affect water quality can include the presence of flocks of birds, proximity to a busy harbour, wind, currents and tides.

What you do on a beach or in the sea can also contribute to the risk of illness. Total immersion in the water (either in a stream running across the beach, or the sea water itself), and swallowing the water, increases the potential for acquiring an infection, as does spending large amounts of time in the water.

The HPA works closely with the Environment Agency, the Local Authorities, DEFRA, water companies and other partners to help ensure England's bathing waters are as clean as reasonably possible.

Water companies are responsible for minimising the opportunities for untreated human sewage to enter the sea. However, under certain conditions, such as heavy rainfall, there is potential for designated bathing waters to become contaminated. This may be caused, for example, by misconnected drains, leaking septic tanks and combined sewer overflows (CSOs) in the vicinity of the beach. Many sewers carry both sewage and rain water drainage and they can become overloaded in heavy downpours. Some sewers are equipped with CSOs which release excess water and sewage into rivers and seas. Without CSOs, sewage could back up and overflow into people's home's, creating a public health risk.


How are the public informed of these risks?

Signs placed by local authorities prominently on designated bathing beaches inform the public of important safety messages about the particular beach, general bathing water quality and if there is a stream that runs across the beach.

The HPA advises four steps to reduce the risk of illness for adults and children visiting beaches:

  • Do not swallow the sea water or the water from beach streams
  • Avoid splashing sea or stream water into your mouth
  • Wash hands using soap and water  ensuring that all wet sand is removed from hands before eating
  • Observe local beach safety advice

 In most cases any infection (such as an upset tummy) will be mild and self treatable. However if symptoms persist it is advisable to consult a GP.

In the case of a pollution incident, extra (usually temporary) signs will be erected by the Local Authority to alert the public to the possibility of an increase in risk of acquiring an infection if they enter the water, and advising them to stay out of the sea/stream. On a lifeguarded beach, red flags are used to advise people to stay out of the sea where appropriate.

Further information on bathing water quality is available from the Enviroment Agency: