The Outdoor Swimming Society UK: How to Join and What It Means for Wild Swimmers
On a grey Tuesday morning in October, a retired schoolteacher from Derbyshire walked down a muddy path to Ladybower Reservoir, stripped to her swimming costume, and lowered herself into water that was barely nine degrees. She had been doing this for three years. What changed everything for her, she later wrote on a forum, was finding the Outdoor Swimming Society — not just the website, but the community, the knowledge, and the quiet confidence it gave her to get in the water without feeling like she was doing something mad.
That story is not unusual. Across England, Scotland, and Wales, hundreds of thousands of people have discovered open water swimming through the Outdoor Swimming Society (OSS), and the organisation has played a central role in shaping how the UK talks about, practises, and legislates around wild swimming. If you are thinking about getting into outdoor swimming — whether in a mountain tarn in the Lake District, a chalk stream in Hampshire, or the sea off the Pembrokeshire coast — understanding the OSS is a very sensible place to start.
What Is the Outdoor Swimming Society?
The Outdoor Swimming Society was founded in 2006 by Kate Rew, a journalist and passionate open water swimmer who wanted to create a community for people who swam outdoors rather than in pools. At the time, wild swimming in the UK was often treated with suspicion by landowners, local councils, and health and safety authorities. The OSS challenged that culture — not through confrontation, but through education, celebration, and a straightforward argument: swimming in natural water is a normal, healthy, deeply British thing to do.
Today the OSS describes itself as a not-for-profit organisation and community. It is not a membership club in the traditional sense, with committees and subscription tiers and annual general meetings. It is something looser and arguably more powerful: a platform, a resource, and a movement. Its website hosts one of the largest free databases of open water swimming spots in the UK, covering everything from secret coves in Cornwall to river pools in the Scottish Borders.
The society has been instrumental in influencing public policy. It contributed to discussions around the Water Framework Directive, supported campaigns for cleaner rivers, and has worked alongside organisations such as Surfers Against Sewage and the Rivers Trust to push for better water quality across Britain. It has also been a vocal critic of the water companies whose sewage discharges have polluted rivers and coastlines that swimmers rely on.
How to Join the Outdoor Swimming Society
The Basic Process
Joining the Outdoor Swimming Society is straightforward. You register on the OSS website at outdoorswimmingsociety.com. The registration process asks for your name, email address, and a few details about your swimming experience and interests. There is no formal membership fee required to access the core community resources, though the OSS does encourage financial support through donations and merchandise purchases, which help fund their campaigns and maintain the website.
Once registered, you gain access to the full suite of OSS resources. This includes the swim spot map, the forums, the event listings, and the advice library. You can also contribute to the community by adding your own swim spots, writing reviews, and participating in discussions about water conditions, kit, safety, and swimming technique.
What You Get as a Member
The swim spot database alone is worth the registration. The OSS map covers thousands of locations across the UK, with user-generated reviews that give you a realistic picture of what to expect. Unlike a guidebook, which becomes outdated the moment it is printed, the OSS database is updated regularly by the community. If a popular river pool in the Yorkshire Dales has recently been affected by a cattle farm upstream, chances are someone has noted it. If a hidden beach in Argyll has suddenly become accessible via a new footpath, a member will have flagged it.
The OSS also sends out newsletters and updates to registered members, covering news about water quality, upcoming events such as the Great East Swim and other affiliated open water events, and seasonal advice. In winter, these newsletters are particularly useful for cold water swimmers who want guidance on acclimatisation and safety.
The OSS App
The society has also developed a companion app that makes the swim spot database accessible on mobile devices. For anyone planning a spontaneous wild swimming trip — pulling off the A82 on the way through Glen Coe, for example, and wanting to know whether the loch at the bottom of that slope is swimmable — having the app loaded on your phone is genuinely practical. The app allows you to search by location, filter by type of water (river, lake, sea, lido), and see user ratings and recent comments about conditions.
Understanding What the OSS Stands For
Access Rights and the Law in the UK
One of the most valuable things the OSS does is provide clear, honest information about access rights to open water in the UK — a topic that confuses even experienced swimmers. The legal position varies significantly across the four nations.
In Scotland, the Land Reform (Scotland) Act 2003 established a right of responsible access to most land and inland water, including rivers and lochs. This means that in Scotland, wild swimming is legally protected as a right, provided you behave responsibly. You can swim in Loch Lomond, the River Tay, or Loch Morlich without fear of legal trespass. This is why Scotland has such a thriving wild swimming culture and why spots like the Fairy Pools on the Isle of Skye and the pools at Steall Falls in Glen Nevis attract swimmers from across Britain and beyond.
In England and Wales, the situation is more complicated. There is no general right of access to rivers and lakes equivalent to Scotland’s legislation. Rivers in England and Wales are generally privately owned, and swimming in them is technically trespass in many cases, though trespass is a civil rather than criminal matter in most circumstances. The OSS has long campaigned for improved access rights in England and Wales, arguing that the current legal framework is both unfair and outdated.
The OSS website provides a plain-language guide to this legal landscape, which is essential reading for any new wild swimmer in England and Wales. It explains which waterways have historical rights of navigation (and therefore arguably rights of access for swimmers), where landowners are known to welcome swimmers, and how to approach situations where your right to swim is challenged.
Water Quality and the Sewage Crisis
The OSS has been one of the most prominent voices in the campaign against sewage pollution in UK waterways. Since the privatisation of water companies in England and Wales in 1989, the dumping of untreated or partially treated sewage into rivers and coastal waters has become a serious and well-documented problem. Organisations including the OSS, Surfers Against Sewage, and the Rivers Trust have used water quality data, legal challenges, and public campaigns to put pressure on the Environment Agency and Ofwat to hold water companies accountable.
For swimmers, the practical implication is that not all natural water in the UK is safe to swim in at all times. The OSS website and app include water quality information where available, and the society advises members to check the Environment Agency’s Swimfo service, which monitors bathing water quality at designated swimming sites across England. In Wales, Natural Resources Wales performs a similar function. Scotland has its own monitoring regime through the Scottish Environment Protection Agency (SEPA).
The OSS also advises swimmers to avoid entering the water for at least 48 hours after heavy rainfall, when surface run-off and combined sewer overflows are most likely to have contaminated rivers and beaches. This is particularly relevant for popular river swimming spots such as the River Wye in Herefordshire (which has suffered serious pollution from agricultural run-off), the Thames above Oxford, and many streams in heavily farmed lowland areas.
Safety: What the OSS Teaches and Why It Matters
Cold Water Shock and Acclimatisation
The OSS is unequivocal about safety, and it does not dress up risks in comforting language. Cold water shock — the involuntary gasping response triggered by sudden immersion in cold water — is the leading cause of drowning in UK open water. It can affect even strong swimmers and can occur in water as warm as fifteen degrees. The OSS safety guidance explains how cold water shock works, why it is so dangerous, and how to mitigate it through gradual acclimatisation and controlled entry into the water.
The guidance recommends entering cold water slowly, allowing your breathing to settle before putting your face in, and never jumping into cold water if you are not an experienced cold water swimmer who has acclimatised over time. It also strongly advises against swimming alone, particularly in cold water or in unfamiliar locations.
Know Before You Go
The society promotes a sensible framework for assessing a new swimming spot, which covers water temperature, currents, depth, entry and exit points, and what to do if something goes wrong. This is practical, unglamorous advice — the kind that does not make for exciting Instagram content but genuinely keeps people safe.
For river swimmers in particular, the OSS warns about underwater currents, weirs (which create dangerous hydraulic traps that can hold a swimmer underwater), and the deceptive power of flood water. The River Exe in Devon, the River Dart in Dartmoor, and the River Swale in the Yorkshire Dales are all beautiful swimming rivers with well-established wild swimming spots, but they are also rivers that can change character rapidly after rainfall. The OSS provides the context to understand this, which a simple Google search for “wild swimming Devon” will not.
Moving Forward
Once you have the fundamentals in place, the possibilities open up considerably. The UK offers fantastic opportunities for anyone interested in this hobby, and with the right foundation you will be well placed to make the most of them.
