IT'S happened quietly, insidiously even, but within a generation outdoor swimming in this country – now known as "wild swimming" – has virtually come to an end.

Sea bathing is still popular, of course, if the weather is right, but swimming in rivers, lakes and ponds has been discouraged, mostly because of fears of pollution, paedophile concerns and ever more stringent health and safety regulations.

Litigation from people who might injure themselves has also been a major factor.

Local authority outdoor pools have also been feeling the squeeze with just a handful still operating throughout the West Country

But as 49-year-old Midlands swimming enthusiast Chris Ayriss points out in Hung Out to Dry – Swimming and British Culture we, in the West, are lucky to still have access to al fresco bathing.

In fact outdoor swimming in an old quarry in Bristol remains as popular as ever – but more of that well kept secret later.

Banned on health grounds since 1978 when a dangerous bug was discovered, swimming and relaxing in Bath's naturally heated waters can now be enjoyed once more at the Thermae Spa.

It's a bit pricey but where else in the country can you go swimming at roof top level during the winter months?

Nevertheless the old, lead lined Roman open pool, once enjoyed by hundreds of people during the Bath Festival, still remains out of bounds.

Just down the road, courtesy of the District Swimming Club, you can enjoy river bathing at Farleigh Hungerford, near Bradford-on-Avon.

"It's a real survivor – the very last river bathing station left in the whole country" says Chris.

But even here, along the River Avon, things aren't as free and easy as they used to be.

River pollution is no problem – the water is regularly tested by officialdom – but a few years ago the health and safety inspectorate arrived on the scene and insisted that the diving stage be dismantled.

A springboard had to go too, leaving only a simple wooden plank as a means of diving into the deep, cool waters.

"It's a real shame the authorities feel they have to make decisions for us – rather than letting people use their common sense" says Chris.

The facilities here might be basic but the club, which has riverside lawns on which bathers can picnic, dry off and enjoy the sun, is well used – in fact there are more than 2,000 members.

A few miles up the M4, at the Cotswold Water Park, is another popular al fresco swimming facility, this time complete with a sandy, man-made "beach".

Opened in 1981, and advertised as a Children's Bathing Beach, it's actually a disused gravel pit.

The shallow swimming area is clearly defined, sloping down to six feet or so, and there are life guards.

The water, on summer days anyway, is clear, warm and free of algae with fish kept away from the area by a boom and wire mesh.

Despite there being a charge to enter the complex, which also offers a play area, cafés and visitor centre, it is very popular.

"The vast majority of visitors arrive with their cars loaded with inflatable boats, deck chairs and play equipment" says Chris

"This water park shows at firsthand just how we, as a nation, are missing out on what nature has to offer" he adds.

Back in Bristol Chris is also full of praise for Henleaze Swimming Club who have been enjoying al fresco swimming in a disused quarry in Lake Road since 1919.

So much, he says, for always being told as children that we should NEVER swim in quarries.

Unlike the Cotswold Water Park there are no shallows here and all club members, of whatever age, have to prove that they are good, capable swimmers before being allowed in.

This is also a private club, a very popular one with limited parking, so there is the inevitable waiting list to become a member.

"Henleaze has been described as a secret garden – a time capsule," says Chris, who was invited to spend a day there.

"Reminiscent of Henley-uponThames, it really is a remarkable place, a swimmers' refuge surrounded by houses and hidden, like a shy oasis, amid the trees.

"The water quality is excellent – spring water in fact – and children can attend unaccompanied once they reach 13.

"The focal point is, without doubt, the diving stage with its three platforms and two spring boards.

"Henleaze is living proof that open water swimming can be safe, diving need not be dangerous and that people can act sensibly.

"Despite the influence of the Health and Safety Executive, fun in the sun is still available in Bristol, due in no small measure to the determination and resilience of a small group of dedicated committee members."

From the Romans right through to the Georgians – who, after all, introduced the world to sea bathing – there have been ever-changing attitudes towards cleanliness, bathing and nudity.

And let's not forget the Victorians with their mania for building public swimming baths – places of which they were so proud… and we are now so rapidly demolishing.

As Chris Ayriss reveals in this labour of love – it took him 12 years to research and write – the whole story makes for a fascinating social history.

■ Hung Out to Dry – Swimming And British Culture is by Chris Ayriss and costs £12.50. Published by Lulu.com the book can be ordered via the website www.hungouttodry.co.uk or from most Bristol's bookshops. Alternatively you can call the author on 0116 247 1307 or 07849 105 466.