Designated Bathing Water Rivers UK: 38 Tested Inland Sites

Of all the rivers and lakes in England, only 38 swimming spots are designated bathing waters, the official status that means the Environment Agency samples the water through the summer and publishes a quality rating. Twenty of those are stretches of river, and six of the twenty were only designated in 2026. Everywhere else, from the river pool behind a glamping site to the lake a retreat calls “wild swimming”, nobody is testing the water on a regular basis. That is not the same as dirty. It means there is no data either way.

The ratings that do exist split sharply. England’s designated lakes mostly come out Excellent. Its designated rivers mostly do not: of the 14 river sites with a 2025 classification, 12 were rated Poor. Here is the full inland list, taken from the Environment Agency’s bathing water register on 21 October 2026, with the latest rating for each.

Why designation matters for a swim

A designated bathing water is sampled up to 20 times each season, from mid-May to the end of September, for two bacteria that point to sewage or animal waste. The results are published on the Environment Agency’s Swimfo service as they come in, and each November they are rolled into a classification of Excellent, Good, Sufficient or Poor based on four seasons of samples. A Poor site has to put up advice against bathing for the next season. Our page on bathing water classifications explains the grades and the November 2025 rule changes in full.

Designation does not make a river clean. It makes it measured, and it puts a legal duty on the Environment Agency and the water company to work on the pollution sources. That is why campaign groups apply for it.

Designated lakes and ponds

Eighteen lake and pond sites are designated, and on the 2025 ratings they are where the clean inland water is.

Twelve Excellent, four Good, one Sufficient and one Poor. Some of these are managed swimming venues rather than open shores: the Hampstead Heath ponds are run by the City of London Corporation with paid entry, and Henleaze Lake is a members’ swimming club. Check how each one works before you plan a trip around it.

Designated rivers with a rating

Fourteen river sites have a 2025 classification. Only two passed.

The Wharfe at Ilkley was England’s first designated river bathing water, in 2021, and it has not yet reached the minimum standard. Under the old rules, five Poor years in a row meant losing designation; since November 2025 ministers decide case by case, so long-running Poor sites can stay monitored while the clean-up continues.

A Poor rating is not a ban, and it does not mean the river is polluted every day. It means that across four seasons too many samples, often the ones taken after rain, failed the standard. The in-season results on each Swimfo profile show how much a site’s readings jump around.

Rivers designated in 2026

Six more river stretches were designated in 2026, in time for the season that opened on 15 May, from a batch of 13 sites that Defra put out to consultation in February. They have been sampled for the first time this summer, and their first ratings are due when the 2026 classifications are published in November.

The rest of the 2026 batch were coastal or estuary sites, including Lostwithiel on the tidal River Fowey.

Estuary sites: river water, coastal rules

The register lists another group of “transitional” bathing waters, where a river meets the sea. They include the Dart Estuary at Dittisham and Warfleet Creek (both Excellent) and at Steamer Quay and Stoke Gabriel (both Poor), the River Deben at Waldringfield (Good), Manningtree on the Stour Estuary (Good) and Coastguards Beach on the Erme Estuary (Poor). If a retreat offers a tidal river swim in south Devon or Suffolk, look it up on Swimfo by name.

What this means when you book a retreat

1. Ask where the swim is. If the venue names a river or lake that is not on these lists, there is no official testing. That is the case for most wild swimming retreats in England.
2. If it is designated, look at the profile, not just the grade. Swimfo shows this season’s individual results and, at some sites, daily pollution risk warnings after rain.
3. Treat rain as the real risk. The usual rule among open water swimmers is to stay out for 48 hours after heavy rain, rated site or not.
4. Out of season, nobody is testing. Sampling stops at the end of September. Autumn and winter dips run on trust and on the water company’s storm overflow map.

The cold itself is the bigger day-to-day risk for most people in a British lake in October; read our cold water immersion safety page before a first winter swim. If you want the cold without the water quality question, an outdoor spa with a cold plunge gives you the same shock in tested water.

Wales and Scotland run their own lists, through Natural Resources Wales and the Scottish Environment Protection Agency, and are not included here.

Frequently asked questions

How many rivers are designated bathing waters in England? Twenty, on the Environment Agency register in October 2026. Fourteen have a 2025 rating, and six were designated in 2026 and will get their first rating in November 2026.

What was the first designated river bathing water in the UK? The River Wharfe at Cromwheel, Ilkley, designated in 2021. It was rated Poor again in 2025.

Which designated rivers are rated good? On the 2025 ratings, only Friars Meadow on the River Stour in Suffolk was rated Good, and Wallingford Beach on the River Thames was rated Sufficient. The other 12 rated river sites were Poor.

Are lakes cleaner than rivers for swimming? Among designated sites, yes. Twelve of England’s 18 designated lakes and ponds were rated Excellent in 2025, against none of its rivers. Lakes are usually less exposed to sewer overflows and farm run-off upstream.

Is it safe to swim in a river that is not a designated bathing water? There is no official data to say either way, because only designated sites are routinely tested. Avoid swimming after heavy rain, check the water company’s storm overflow map, and do not swallow the water.

When are bathing water ratings published? Each November, after the May to September sampling season. The 2026 ratings, including the first for the six new river sites, are due in November 2026.