The full list of beaches

The Cornish resort of Rock, dubbed Chelsea-on-Sea after princes William and Harry began frequenting its beaches and bars, has been exposed as having some of the dirtiest sea water in the country.

The beach at the town, where pebble-dashed bungalows sell for £3 million, is one of 78 in Britain that have failed to reach the European Commission’s mandatory standard for water quality.

Almost a sixth of the beaches in the 2009 Good Beach Guide have lost their recommendation for excellent water quality — the biggest year-on-year fall in the 22 years that the Marine Conservation Society (MCS) has produced the guide.

For the first time since 2002 the number of recommended beaches is below 50 per cent of those tested. Water samples were taken from 777 British beaches, but only 370 were recommended this year for swimming, surfing or paddling.

Even popular resorts such as Blackpool, Weston-super-Mare, Teignmouth, Lyme Regis, Eastbourne, Southwold and Hunstanton achieved only a “basic pass” for water cleanliness — the minimum required by the European Commission. The North West has the lowest number of recommended beaches.

Bathing in dirty water can cause ear, nose, throat and eye infections, diarrhoea and gastroenteritis. Experts are blaming the results on last summer’s heavy rainfall, which increased pollution in rivers and seas. The water samples were taken between May and September last year.

Thomas Bell, the society’s coastal pollution officer, is convinced that sewerage and storm overflow systems need to be updated urgently.

He said: “MCS is now recommending 25 per cent fewer beaches than three years ago and we’re becoming concerned that the existing infrastructure for handling storm pollution may not be up to the job.

“There are 22,000 combined sewer overflows around the country and 500 near beaches. They are supposed to cope with a flooding emergency. We suspect there is a design fault, however, and the seasonal population increase combined with steady rain fills the sewers beyond their tipping point. We believe that places like Rock are suffering from excessive discharge from these overflows.”

He called on the Environment Agency and water companies to find the cause of the pollution. One possibility is that run-off from farmland, such as fertiliser, slurry and cattle or sheep faeces, is contaminating rivers.

Mr Bell added: “It’s almost a lucky dip for bathers. If it’s tipping with rain you take your chances in the water but if it’s a long, hot, dry summer water quality will improve.”

His advice was to choose beaches with a good record for water quality, to stay out of the water for at least 24 hours after heavy rainfall and to report pollution to the marine society.

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