Safe, clean beaches are vital for happy holidays and coastal communities that depend on tourism. However, some beaches were at risk of losing their designation as safe bathing waters because there was no way to measure or report real-time pollution levels.

It had been assumed that the level of pollution in bathing waters was the same throughout the day. However, earlier research carried out by Aberystwyth University’s Centre for Research in Environmental Health (CREH), revealed that levels can vary, and a sample taken in the morning can be very different from one taken in the afternoon.

What was needed was a way to predict water quality in real time to allow people to make an informed decision about whether they feel it’s safe to swim.

Predicting water quality

Research by the CREH team focused on how to:

  • predict the quality of seawater at recreational beaches in real time
  • inform the public of any health risks should they choose to swim there

The team created a pollution risk forecasting (PRF) tool, which they trialled at Swansea Bay, an urban beach in Wales’s second-largest city. They then developed the tool at Cemaes Bay, a small rural beach in Anglesey, and other popular tourist beaches in Pembrokeshire and Ceredigion.

The results from all the trial sites showed significant differences in pollution levels depending on the time of day the sample was taken.

Safeguarding public health

The PRF tool predicts water quality throughout the day. It safeguards public health by giving people the information they need to decide whether bathing waters are safe. This ‘informed choice’ for recreational waters is recommended in World Health Organisation (WHO) guidelines.

The tool also helps to protect the safe bathing water classification at many sites, safeguarding the economies of communities that rely on tourism.

The CREH team’s research has influenced UK and international public policy and practice. As a result of their findings:

  • the WHO revised its Guidelines for Safe Recreational Water Environments
  • the European Union revised its bathing water directive that sets standards for EU bathing waters and is in force across more than 22,000 European beaches
  • the Environment Agency revised its system to forecast pollution risk at more than 150 bathing waters across the UK

Lead researcher, Professor Kay, also served as a technical adviser to:

  • Blue Flag International, which administers the worldwide Blue Flag Awards for bathing waters
  • The 2016 Rio de Janeiro Olympic Games, where he analysed and reported on water quality for events in nearshore waters off the beaches surrounding Rio.

Research team

Professor David Kay, Dr Mark Wyer, Dr Carl Stapleton, Dr Lorna Fewtrell and Dr Cheryl Davies – Aberystwyth University’s Centre for Research in Environmental Health (CREH)

Read the full REF impact case study