Answer
Do I need planning permission to convert a swimming pool to a natural pond?
Usually not, but check designated land, listed status and protected species first.
In short
Usually not. Converting an existing swimming pool to a domestic natural pond is normally permitted development. The things to check first are designated land or a listed property, and protected species: if newts or other protected wildlife are present near existing water, an ecological survey and sometimes a licence are needed before work starts.
A note
General guidance, not advice. Rules vary by site, and Article 4 directions or conditions can change what applies. Check with your local authority and the Planning Portal.
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