Many old people can remember the joy of bathing and of swimming in natural water in the countryside, that it is a river, a lake or a pond, with the sun or the moonlight, with or without clothing, as a group or a recluse. Alas, the situation changed well and the majority of the children today will be able to never know this feeling and this, because of many reasons such as healthiness, safety, the violation of the land property, polluted water ...

However, all is not lost because there are now natural systems for swimming private and public which can be built for the pleasure of each one. The natural swimming pools are based on the biological principle of balance of the ponds and the lakes which one so much abundantly found in the landscape in the past.

The comparison of an ecological swimming pool to a natural lake is deliberated since it is this which is really (càd a large pond with a special provision so that the people appreciate water as well as the various creatures which are attracted with it). Nature offers the best examples on the matter.