An open-water swimmer has hit out at Thames Water after creating a postbox topper that criticises sewage dumping in Marlow.

Samantha Sutton took up open water swimming three years ago but for the last two winters has been unable to take to the water in the River Thames due to concerns of sewage dumping in the area.

This urged Ms Sutton, 55, from Marlow, to create a post box topper that takes aim at the water company's failure to manage sewage spills which sees them face a £104m from Ofwat.

The penalties relate to water firms’ management of their wastewater treatment and sewer systems, which have come under heavy criticism for releasing too much pollution into rivers.

She said: “I started wild swimming three years ago and absolutely love it.

“I do it for the health benefits of cold water, being immersed in nature and seeing wildlife from a different angle, the tranquillity of the river, especially in winter and all the new friends I have made whilst doing it. 

“For a while now, I’ve seen postbox toppers around and it made me want to make one myself, but I wanted to convey a message, so decided to do a protest one.

“For the last two winters, we’ve not swum in the river much because of the constant sewage dumping by Thames Water. "

Ofwat has also confirmed recently that Thames Water must appoint an independent monitor to oversee its progress until its credit rating is restored.

The country’s biggest water supplier breached its licence agreements after losing its “investment-grade” credit ratings, which indicates whether its debt is of good or bad quality, and meaning it is even harder for the firm to borrow money.

Thames Water is now in the grip of a funding crisis having built up more than £15 billion of debt, and with only enough money to continue trading until the end of May 2025.

A Thames Water spokesperson said: “The health of our rivers is affected by many factors, including farming, industry, wildlife, run off from roads, and discharges from sewage systems. Everyone has a critical role to play. 

 “While all storm discharges are unacceptable, the sewage system was historically designed to work in this way, to prevent sewage backing up into people’s homes. 

“As our infrastructure ages, and our population grows, more investment will be required.

“Thames Water has a clear and achievable plan to upgrade 250 of our facilities, including Little Marlow sewage treatment works, to ensure we play our part.

"We’ve put transparency at the heart of what we do, and we were the first water company to publish a real-time data map on our website, which in its first year has been viewed over 350,000 times.”