The cleanest and best beaches for a bank holiday swim

Last week, hundreds of swimmers, surfers and paddleboarders took to the waters to protest against the dumping of raw sewage in our waterways.

Surfers Against Sewage, the campaign group behind the Paddle Out protests, reports that there were 592,478 untreated sewage discharges across the UK in 2024 - lasting for a total of 4,786,038 hours.

It’s a health concern for anyone planning a sea dip in the UK this summer. Want to know what the water quality is like at your favourite beach? Ahead of the bank holiday weekend, we reveal the cleanest (and dirtiest) seas at some of the UK’s best seaside towns.

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Bamburgh, Northumberland

This Northumberland beauty is consistently rated the best seaside town in the UK in our annual survey - receiving the full five stars for its beach and scenery. The vast sweep of golden sand is overlooked by the majestic Bamburgh Castle, standing proud on a rocky outcrop. 

And for those hardy enough to brave a dip in the bracing North Sea, there’s good news. Bamburgh’s bathing water is classified as excellent - the highest and cleanest rating designated by the Environment Agency. 

Portmeiron, Gwynedd (Wales)

This quirky destination in Gwynedd was dreamed up in the 1920s by Welsh architect Sir Clough Williams-Ellis, who was inspired by the Italian Riviera. The result is an extravagant jumble of domes, colonnades and towers set among sub-tropical gardens.

You’re spoilt for choice when it comes to local beaches. Peaceful Harlech, backed by sand dunes and part of the Snowdonia National Park, is great for a swim - its bathing waters have been classified as excellent by government agency Natural Resources Wales.

St Andrews, Fife (Scotland)

It’s your favourite seaside town in Scotland - loved for its cobblestone alleyways lined with independent shops, ice cream parlours and fancy bistros.

East Sands is a sandy beach on the south side of the old harbour and on the Fife Coastal Path - ideal for walkers. It’s also great for a swim, and its bathing waters classified as excellent by SEPA (the Scottish Environment Protection Agency). 

West Sands, a 15-minute-walk from the centre of town, is currently rated good - meaning the water quality is generally not as clean as its near neighbour. 

Tynemouth, North Tyneside

The town, with its Victorian boulevards and historic castle ruins on a craggy headland, is a beauty in its own right. But it also overlooks the mile-long golden stretch of Long Sands beach, with the smaller King Edward’s Bay tucked around the corner between sheltering cliffs. 

Don’t hesitate to change into your swimwear: both beaches hold Blue Flag status, with their bathing waters classified as excellent. 

Just give Cullercoats Bay a miss. The small, sandy crescent-shaped beach down the road has been rated poor - the lowest possible classification - meaning it failed to meet the minimum standards for water quality. And while the beach remains open for people to enjoy, swimming here is not advised.

St David’s, Pembrokeshire (Wales)

Not by the sea but not far from it, the UK’s smallest city - St Davids - is an excellent base to explore the single-track roads that twist down to sheltered bays. Whitesands Bay, popular with surfers, is the most famous - a magnificent Blue Flag beach flanked by rocky cliffs on the Pembrokeshire Coast. 

Its bathing waters are classified as excellent but it isn’t alone: nearby Caerfai, a short walk from the centre and accessible by steep steps, is just as clean. It has a sandy beach at low tide that's perfect for swimming and rockpooling.

Southwold, Suffolk

Everything about this Suffolk town is classy: from the well-maintained pastel-painted beach huts to the tasteful pier with its collection of eccentric, old-penny-operated arcade games. Throw in a lighthouse, Georgian houses and a few Adnams pubs and you have all the ingredients for a genteel day by the sea. 

There are two beaches: the Denes, a sand and shingle beach backed by scrubby dunes, and Southwold Pier beach. The latter is more crowded but the sea is cleaner - here the bathing waters are classified as excellent, a step up from the Denes (most recently designated good).  

Sewage in our seas: the health risks

Human sewage contains bacteria and viruses that can make us sick if we come into contact with polluted waters. Illnesses include everything from skin, eye and ear infections to diarrhoea and vomiting. Some people may be more susceptible than others, such as young children, the elderly or those with weakened immune systems.

Whatever the bathing water classification, it’s a good idea to check in real time whether it’s safe to swim. The free Safer Seas & Rivers Service app can give live updates when untreated sewage is discharged at swimming spots in 600 locations across the UK. 

Find out more with our advice article about how to check for raw sewage at beaches near you. Of course, you also need to be wary of winds, tides, currents and water temperature before taking the plunge. 

How to stay safe from sewage when swimming

1. Check real-time predictions of water quality or the most recent bathing water classification at Swimfo.
2. Take notice of any local safety signs. 
3. Avoid swimming for 48 hours after heavy rainfall. Sewer overflows are more likely to discharge during a deluge, causing an increase in harmful bacteria entering the water.
4. Wear a wetsuit to minimise your body’s contact with the water. Keep any cuts or sores covered with a waterproof plaster to avoid infection.
5. Try not to swallow any water, and wash your hands thoroughly before eating or drinking.