Waste water containing sewage has polluted the coastline 30 times over the last six weeks.

Beaches in Tankerton and Herne Bay have had 16 and 14 spills respectively since the bathing season began on May 15.

But Southern Water, the company responsible for the discharges, insists the spills consist of just 0.01% waste.

Organiser of the Herne Bay Pier to Pier Swim Giles Seaford says he will be particularly vigilant ahead of the event in two weeks’ time.

“Having learned of this, I will definitely email the foreshore services to ask what the readings for the water are, whether he is taking more precautions and if he will suggest anything to me,” he said.

“All I’m concerned about is how it’s going to affect the swimmers on the day.

“But we haven’t had any problems with the water around our event, so we’ve been fairly fortunate.”

Southern Water says the spillages occur when the sewage system is overloaded following heavy downpours.

The swim, which is due to take place on Sunday, July 21, does have a back-up date in case the water does prove to be unsafe to swim in.

However, Mr Seaford says forecasts suggest there will not be any heavy rainfall in the build-up to the event.

“We can’t run our events without having water tests done a week before, the day before and on the day of the event,” he explained.

“If the pollution levels are too high we do have a reserve date.

“The foreshore manager has given me a long-range forecast suggesting there’s not likely to be heavy rainfall on the day and he’s not mentioned any issues with the water.”

The figures, which have been compiled by marine conservation charity Surfers Against Sewage, reveal Southern Water has had more spillages than any other company since May.

The discharges have also been recorded in Brighton Central and Aldwick Beach, Bognor Regis.

Water services regulator Ofwat fined Southern £3m last month for spillages, equipment failures and inaccurately reporting the performance of its waste treatment sites.

Hugo Tagholm, of Surfers Against Sewage, said: “It’s unacceptable that Southern Water is the worst performing water company for sewage spills so far this bathing season.“Water companies need to do more to stop these spills.”

The Environment Agency says the risk of encountering reduced water quality increases after rainfall and takes up to three days for it to return to normal.

Southern spokesman Simon Fluendy said: “The reason we are permitted by the Environment Agency to discharge storm water after a downpour is simple – if we don’t allow this highly dilute storm water out then our customers’ homes will flood.

“Storm discharges are around 0.01 per cent wastewater.

"We give data on storm overflows in real-time to allow recreational water users to make a judgement as to whether they want to go in the water. The quality of both Herne Bay and Tankerton beaches are rated ‘Excellent’ by the Environment Agency.”

Canterbury City Council spokesman Leo Whitlock said: “It is definitely safe to swim in the sea in Tankerton and Herne Bay.

“Bathing water in Tankerton is currently classified as excellent, Herne Bay central as good and Herne Bay East as excellent.

“There are no live incidents and we would put up signs at the beaches to warn bathers if there were.”

“We would manage any such incident in conjunction with the Environment Agency, which monitors bathing water quality between May and September, and Southern Water.

“We talk to both throughout the year.”

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