A water company fined a record GBP90m for dumping raw sewage is facing a ratepayers’ revolt over its continued discharges into the sea. A non-payment campaign against Southern Water, initiated by four residents of Whitstable in Kent, is understood to be growing.

The protesters this week were given the support of Bob Geldof, who lives in nearby Faversham. According to the Kent Online website, Geldof told an audience in the town: “Don’t pay your water bills to Southern Water – they can fuck off. God bless the people of Whitstable. I’m straight there to join them. In fact, I’ll join them immediately.”

Those refusing to pay their bills include a local Conservative councillor, Ashley Clark. In a letter to the water company, he wrote: “I have no intention of contributing to the GBP90m fine recently imposed on that company for criminal activity.

“Throughout the summer Southern Water has continued to send my untreated sewerage, along with that of other local people, directly into the sea, which I use on a daily basis to swim from April to October.

“I find the thought of swimming in a mixture of local sewerage and seawater totally abhorrent and not something that I should be charged for. If I paid someone to clear out my garage and take rubbish away to the tip but instead they fly-tipped it into the countryside, I would be upset. Canterbury city council prosecutes offenders for that type of activity.

“Yet Southern Water continues to fly-tip sewage into my bathing water with impunity.”

Southern was fined GBP90m in July for spilling billions of litres of raw sewage into the sea around Whitstable and the Hampshire coast.

Mr Justice Jeremy Johnson, sentencing the privatised water company at Canterbury crown court, said the offences showed a shocking and wholesale disregard for the environment.

He said the company had a history of criminal activity for its “previous and persistent pollution of the environment”, with 168 previous offences and cautions. But he said: “There is no evidence the company took any notice of the penalties imposed or the remarks of the courts. Its offending simply continued.”

Beaches in Kent have been closed three times in the past three months because of releases of raw sewage by Southern Water.

The company said the bills customers paid were “absolutely crucial” to allow it to make the investments needed to deliver environmental benefits, better customer service and boost local economies.

It announced that it was setting up a taskforce to cut sewage releases via storm overflows by 80% by 2030. “Southern Water’s customers have made it clear the use of storm releases is no longer acceptable,” the company said.

The Whitstable author Julie Wassmer is another of the non-payers. In a letter she told the company she was withholding the wastewater treatment charge of GBP168.08 on her bill.

“It cannot be right for criminal activity to be rewarded; for families to have been forced from beaches and out of the sea, for residents to have had to sweep sewage from a footbridge so that local children do not have to tread in excrement on their way to school, and for Southern Water and its shareholders to continue to make huge profits from all this … so I am therefore exercising my consumer rights by withholding payment to Southern Water.”

Demonstrations were held in Margate and Whitstable this autumn calling for an end to raw sewage releases into the sea.

Geldof, speaking to an audience at a climate change event at Faversham Assembly Rooms, was reported as saying: “I can’t understand why this giant utility company can’t be held to account. I really don’t understand it.”

The company publicly releases information on discharges of sewage and wastewater from its storm overflows via the Beachbuoy service, which Southern said had an important role in making people more aware of when and where the releases took place.

A spokesperson said: “Southern Water is determined to deliver environmental improvements for our customers. We are spending GBP2bn on improvements between 2020 and 2025 and we’ve promised to cut pollution incidents by 80% by 2025.”