If more warning was needed not to go swimming in a river on your next staycation - this is it.
A new investigation by The Sun newspaper has revealed that nine of our best known waterways are 'shockingly contaminated' with human waste.
The paper launched the study after Gavin & Stacey star Joanna Page's husband James Thornton became ill when he dived into the Aire in Leeds to save her dog.
The results also come a few months after comedian David Walliams suffered severe stomach problems after completing a charity swim in the River Thames.
Water samples from nine of our rivers were delivered to microbiologist Geoff Douglas, a water contamination expert who works for water testing firm DelAgua, who told the paper: "The number of colonies on the Thames sample was shocking.
"Faecal coliforms, from human excrement, are not harmful in themselves but their existence in the water means an increased chance of diseases such as cholera, enterococcus, salmonella, pseudomonas or clostridium."
The nine rivers tested were grouped into three categories of contamination: red (high), amber (medium), and green (low).
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