Terms of use

Hydrionis is a reference resource operated by HEKNO Ltd. It republishes measurements and statistics made by national agencies, regulators and statistical offices, together with analysis Hydrionis computes from them. Every figure carries its source, its method and its licence.

It is not engineering, legal, medical or investment advice, and nothing here should be relied on for a regulatory determination, a design decision, or a judgement about whether water is safe to drink. Drinking water standards are jurisdictional: a limit applies only where it was made. For a concern about the water at your own property, contact your supplier or the relevant regulator.

Hydrionis publishes what its sources published, and its sources sometimes publish values that are wrong. Where that has been found, the values have been withdrawn or refused and the episode written up in the Vault rather than quietly fixed — including the occasions where Hydrionis itself was at fault. That record is the most honest statement available about how much to rely on any given figure.

Rights travel with each source and are not uniform. What you may do with a figure depends on who published it: see licensing for the rules Hydrionis applies, and the source registry for the licence and required attribution on any individual source. Hydrionis’s own analysis, structure and prose are its own work.

HEKNO Ltd, hello@hekno.co.uk. These terms were last reviewed on 2026-08-25.