Urgent improvements needed to UK bathing water forecasts

Updates on the state of coastal and inland waterways must be improved in a bid to protect swimmers from Britain’s ongoing sewage problem. 

A new review, published in the journal WIREs Water, suggests that the current approach to forecasting models are now fit for purpose and fail to keep the public protected when using any of the UK’s designated bathing sites, which now number in excess of 600. 

Existing systems cannot accurately predict the threat of pollution caused by sudden downpours, researchers from the universities of Reading and Oxford argue. Heavy rain leading to an overflow of sewage into streams, rivers, lakes, and marine waters, along with agricultural run-off, are placing the health of swimmers in jeopardy from rapid increases in the concentration of chemicals and bacterial in water systems. Authorities must quickly work to improve forecasting techniques, identifying the dangers of bugs such as E.coli and intestinal enterococci, both of which have potentially deadly consequences. 

‘We expect beaches that are designated for swimming to be clean and safe, but authorities often don’t have good enough information to issue warnings, leaving swimmers and surfers more vulnerable to getting ill,’ said Karolina Krupska, lead author of the study at University of Reading. ‘The way we manage our sewage and land means rivers and seas are frequently polluted, and heavier summer downpours due to climate change is making the problem worse at the time of year when people are most likely to be at the beach.

‘With existing pollution warning systems, beach users don’t have good enough information to decide whether it is safe to go in the water. The science underpinning the next generation of bathing forecasting already exists, but a lack of action means these solutions have not been implemented,’ she continued. ‘We need a more reliable and frequently updated early warning system, to ensure people can safely enjoy a coastal swim with the confidence that they aren’t putting themselves at risk.’

Strengthening protection for UK swimmers using bathing waters should involve a number of key steps, which were also outlined in the report. These include: 

*Increase in bacteria sampling during extreme weather events

*Make better use of existing state-of-the-art high-resolution rainfall predictions to enable localised warnings in a similar way to flood alerts 

*Take advantage of new machine learning forecast methods to provide more regular and accurate warnings for individual locations

More on water pollution: 

https://environmentjournal.online/waste-recycling/sewage-dumping-in-london-increased-five-fold-in-2023/

https://environmentjournal.online/headlines/unlimited-fines-for-water-companies-begin-but-will-this-help/

https://environmentjournal.online/headlines/what-ofwat-penalties-for-failing-uk-water-suppliers-tell-us/

Image: Vladimir Fedotov