How do you find a safe place for wild swimming in rivers and lakes?

A river pool on a hot afternoon, a lake with the mountains upside down in it: inland swimming is one of the great summer pleasures, from Scottish lochs to the emerald pools of an Alpine valley. It also has hazards that are hard to see from the bank. Choosing the spot is most of the safety work, and it starts at home, before you have even packed a towel. None of this makes any water safe; it is about stacking the odds sensibly and following local rules and lifeguards wherever they exist.

Start with known places

• Supervised venues. Many lakes and reservoirs run swimming sessions with safety cover. The Royal Life Saving Society UK recommends lifeguarded or accredited open-water venues, especially for less experienced swimmers.
• Designated bathing waters. In the EU, member states monitor the quality of designated bathing waters during the bathing season, and each site is classified as excellent, good, sufficient or poor. National and regional authorities publish these results, and signs at the site often show them too.
• Local swimming groups. Wild swimming clubs and online groups know which spots are used, where people get in and what changes after rain.

Places nobody swims are not always undiscovered treasures. Sometimes there is a reason.

Water quality

The European Environment Agency explains that bathing water is assessed for bacteria that indicate faecal contamination, which usually comes from untreated wastewater or manure and can rise after heavy rain. Practical habits that follow from that:

• Check official water-quality information where it exists before you go.
• Be wary after heavy rain, when run-off is more likely, and look for any local warnings.
• Skip water that looks or smells wrong: scum, unusual colour, dead fish, or a sign telling you not to swim.
• Cover cuts and wash your hands before eating.

Currents and structures

Rivers move, and they move more than they look. The UK Environment Agency warns people not to go in near weirs, locks, pipes and sluices, because these features are often linked with strong currents, and not to jump or dive in because depth varies and hazards can be hidden.

• Choose slow, wide stretches rather than narrows, bends with fast water or anywhere just below a weir.
• Throw a stick in and watch how fast it moves. If you could not comfortably swim against that, do not swim there.
• Watch for boats on navigable rivers and lakes, and keep out of their channels.
• River levels change. Rain upstream can raise the level and speed of the water quickly, even on a sunny day where you are.

Getting in and out

RLSS UK points out that many rivers and lakes have steep or undercut banks and only a few safe ways in and out. Before you swim:

• Find your exit first, and a second one downstream in case the current carries you.
• Wade in rather than jumping; feel the bottom with your feet.
• Look under the surface for rocks, branches and shopping trolleys.
• Stay in your depth at first, and swim upstream before you swim down, so the current helps you back.

The cold, even in summer

The Environment Agency notes that inland water can be very cold however warm the weather. Get in slowly and keep the first swim short. Our page on cold-water swimming safety explains cold water shock and how to warm up afterwards.

Never alone, and tell someone

RoSPA's open water swimming advice is to swim with a buddy or an organised group, check the weather and currents, and know where you can enter and exit. Tell someone ashore your plan. A bright cap and a tow float make you visible to boats and to your friends. Our wild swim kit list covers the rest of the bag.