Recent media stories have led to much confusion, especially between ecological water quality measures and bathing water quality. Exaggerated headlines have suggested that no river is fit to swim in, based on the fact that no rivers are designated as bathing waters. This OSS post Bathing water designation for local swim spots? suggests considering pros and cons and practicalities before setting up campaigns for designated bathing waters at swim spots. I’ve gone into more detail on this page, Key questions for seeking bathing water designation. Interesting discussions in the Cam River Valley Forum about swimming and bathing places in Cambridge, which have wider relevance (link downloads Word.doc 1 page).
See also on the OSS website, Designated Bathing Waters explained – what they are and why they matter.
In practice, most swimmers can look at the water and can assess instinctively if it is clean enough to swim or dip in. The Outdoor Swimming Society’s Is It Clean? gives some tips: avoid inner city water, places with litter or debris, murky water or scum, or that smell bad. And it’s usually best to avoid swimming after heavy rain, particularly downstream of grazing cattle and of water treatment works, which are mapped by the Rivers Trust for England (link opens large interactive map) as part of their campaign for Rivers Fit To Swim In.
Other issues often misunderstood or the subject of exaggerated fears are blue green algae and Weill’s disease, so here are pieces useful to swimmers:
I have concerns about media reporting on water quality, including the reporting of the most recent figures on ecological river health, and the consequences of this reporting for swimmers, as I explain in this post, Rivers not fit to swim in?