About Stillwater

What this site is

Stillwater documents 28 wild swimming and open-water dipping spots across four water types: rivers, lakes, sea and tidal pools, and lidos. Every entry answers the same short list of questions — how cold is it, how do you get in, how do you get out, and what specifically goes wrong here.

The organising idea is that water temperature is the single most useful fact about a swim spot and the one least often written down properly. So it leads: the front page is a twelve-month temperature dashboard, the seasonal axis is a temperature ranking by month, and every spot page opens with four numbers rather than a photograph.

Everything published here is written and maintained by The Cold Water Desk, the editorial desk behind Stillwater — which is the name that appears in the byline on every spot sheet and as the author of every entry.

Where the figures come from

Monthly means are taken for the top metre of water and rounded to 0.5 °C. Where a national monitoring archive exists we use it — the Environment Agency and SEPA in the UK, Natural Resources Wales, the Swiss FOEN, Slovenia’s ARSO, the Czech CHMI, and Guangdong’s marine monitoring programme in China. Where no official gauge covers a spot, we use long-running local swim-club logs and say so on the page.

Heated pools report their maintained operating temperature instead of an ambient one. That is why a few entries in this library run flat through January while others swing by more than fifteen degrees across the year. We think hiding that difference would be worse than showing it.

Where we draw the line

Stillwater is informational. It is not a lifeguard service, not a safety authority and not a medical source, and nothing here is professional advice. Conditions at every one of these places change within hours: temperatures are monthly means rather than today’s reading, and depth profiles are typical rather than surveyed.

Use these pages to decide where to go and what to expect. Then make the actual judgement at the water, where the signage, the lifeguards and your own eyes have information this site does not.

How the library grows

Spot records are published on a schedule rather than all at once — roughly one every two to four days. A record stays invisible until its publication date passes, at which point it appears in the lists, in the sitemap and in search. The footer of every page shows how many of the 28 records are currently live.