Surfers Against Sewage (SAS) installed a giant inflatable turd at Trevaunance Cove, St Agnes on Wednesday to illustrate that almost half of swimmers and surfers have fallen sick after dipping in the waters in the last year.

A study by St Agnes Water Users Group in conjunction with SAS last year, to measure the impact of sea water pollution on local health, revealed alarmingly high level of E Coli and Intestinal Enterococci in sea water samples collected in the cove.

Surveys were carried out amongst regular swimmers and surfers in Trevaunance Cove, St Agnes in February 2025. Findings were based on 66 responses, using a mix of face-to-face interviews, and online responses from local Facebook forums and emailed responses from members of the St Agnes Surf Lifesaving Club.

Over 45 per cent of respondents revealed they had experienced a health problem from swimming or surfing in the cove during the last year. Almost two-thirds (63 per cent) who fell ill reported suffering multiple bouts of illness, and 86 per cent expressed no confidence in South West Water's ability to clean up the coastal waters.

One respondent confided that their son had terrible stomach cramps since surfing on February 1, leaving him unable to eat for a week. A swimmer with St Agnes Bluetits had to have a surgical procedure to remove an infected cyst after regular dipping, while another respondent suffered regular ear infections and a UTI which tested positive for e-coli in 2024.

Dianne Dunne, co-founder of the St Agnes Water User Group, said: “We’re deeply concerned about the high incidence of health issues reported by water users who swim or surf all year. The tourist season is round the corner, and it’s worrying to think of the risk to vulnerable children and adults who are less able to protect themselves.

“We’ve already seen six sewage releases in Trevaunance in 2025, which is six too many. It’s time for urgent action to eradicate this harmful practice.”

Cllr Pete Mitchell, Cornwall councillor for St Agnes, Mount Hawke and Porthtowan (Liberal Democrat) said: “I’m working very closely with Surfers Against Sewage and South West Water to find ways to remedy the situation. I don’t think we will get there without all parties working together.”

A South West Water spokesperson said: “We are sorry to hear that people have been unwell. However, we haven’t received any information about the tests conducted and therefore it’s not possible for us to comment on what caused them to feel unwell, as there are many reasons that could cause this.

“There are a wide range of factors which can affect water quality in our seas and rivers, including agricultural and urban pollution.

“We are investing significantly at Trevaunance Cove and prioritising our bathing and shellfish waters across the region. We are spending £760 million – that’s around £416,000 a day, every day, over five years – to make our wastewater systems better.”

The Environment Agency has classified the water quality at Trevaunance Cove as excellent.