Thames Water: sewage activists invite CEO Cathryn Ross to swim with them soon after she’d happily ‘take a dip’

Sewage campaigners have invited the CEO of Thames Water to join them swimming in The Thames after she said she would happily “take a dip” in treated sewage water. Henley Mermaids, a group of five women who are longstanding campaigners against river pollution, are challenging Cathryn Ross to join them on Friday 13 October as the women will take a “collective stand against the ongoing sewage pollution”.

Henley Mermaids will be joined by several other campaign groups including the Henley and Marlow River Action Group, Henley Hippos and Ocean Rebellion. The five women said the plight of their swim on Friday is to “campaign for change” and “stop pollution from getting into our rivers”.

The group has extended the invite to Ms Ross to allow her to “experience our river’s plight personally” after she said on Wednesday 13 September, at a meeting in the London Assembly, that she would “take a dip” in a river that is full of treated sewage. Her comments came despite her confirming earlier that this water would still contain “some bacteria”.

The Henley Mermaids said those taking part in the swim will be meeting at Friday Street Slipway in Henley, ready to swim in the water which is situated downstream of the Wargrave Sewage Treatment Works. The group said Henley “is subjected to ‘treated sewage’ discharges into the Thames 24/7” and “a Combined Sewage Overflow (CSO) in the heart of our town has unleashed raw sewage into the Thames on at least eight occasions over the past six months”.

Independent testing by the group during the bathing season, from May to September, found alarming levels of Phosphates and Nitrates, as well as E. coli and Enterococci consistently being detected in Thames21’s Henley Bathing Water Project testing. These bacteria are harmful to human health and directly threaten river wildlife.

The Henley Mermaids told NationalWorld: “So far I have not had an RSVP and do not expect that she will turn up, however, that will be fairly powerful in itself. We’d love lots of people to turn up and give a poorly river voice.” The community call to action event will begin at 2pm on Friday with speeches, fancy dress, banners all included and encouraged by the organisers.

A recent investigation by the BBC found that Thames Water was one of three water companies discharging sewage illegally last year during dry weather. The water company dry-spilled for 1,253 hours in 2022 at 49 overflow sites.

It is likely that more spills would have occurred during this time as the water company only monitors 62% of its overflow points. A Thames Water spokesperson told NationalWorld “there are a number of methodologies for defining and calculating why and how dry day spills occur” and the Environment Agency’s methodology “is still being determined”.