Is it legal to collect and use rainwater in the UK? The answer isn’t necessarily obvious if we look at precedents from elsewhere in the world. In the American state of Colorado, for instance, it is legal to sell water butts, to own them, but not to use them for the purpose for which they are intended! The water rights and laws of the arid Western US states go back 150 years to when it was a case of first come, first served for everything from land to gold digging claims to water rights. So a homeowner is deemed not to own the rainwater that falls on their property and it must not be harvested. The rainwater belongs to the owners of nearby water rights in the expectation that the rainwater will eventually make its way onto their groundwater supplies. It may seem ludicrous to us living in the damp climes of the UK but that system has a grounded basis in history as the article in the Washington Post explains very well. Rumours abound of individuals being prosecuted and even sent to prison for harvesting rainwater off their own roofs.
What Is The Legal Situation In The UK?
Scare stories like these from abroad may have planted seeds of doubt in the minds of UK citizens regarding the legality or otherwise of rainwater harvesting here in Britain. In fact, it is perfectly legal and actually encouraged by most water companies, especially in the drier south eastern counties where rainfall is significantly less than along the west coast.
However, whilst there is nothing to prevent householders from collecting rainwater, there are standards and regulations that apply, especially if a cross-connection is made to the mains water supply. There are also regulations governing the supply of water for consumption, as well as general health and safety rules as one would expect.
What Regulations Apply?
Developers, project managers and owner-installers should be familiar with the following regulatory and advisory initiatives:
Water Regulations Advisory Scheme (WRAS) regulates all aspects of mains water supplies, including the types of valves and fittings that interact with mains water. The most important regulation here is the one pertaining to backflow prevention. Any connection from the mains supply to a rainwater harvesting system must have a physical air gap that prevents any risk of non-potable water being siphoned back in to the mains supply. The relevant legislation includes The Water Supply (Water Fittings) Regulations 1999 (England and Wales) with separate legislation applying to Scotland and Northern Ireland. See the official WRAS website for more information.
BS 8515:2009 Rainwater Harvesting Systems – This Code of Practice aims to achieve consistent risk management, water quality, installation standards, testing and ongoing maintenance of rainwater harvesting systems. It puts forward guidelines for suppliers to ensure they maintain high standards of excellence.
Planning permission – “permitted development” rights encompass rainwater harvesting systems as they are considered a rainwater recycling system and so planning permission is not generally required. As always, check with the relevant planning office. In fact, the inclusion of such an environmentally friendly system in plans for new builds usually counts as a plus point when approval is being considered by the local authority.
Pipe marking – Harvested rainwater must be labelled as non-potable (otherwise known as “non-wholesome” – in other words, not suitable as drinking water). Pipes that convey rainwater, whether below ground or within a property must be identified as such. Similarly valves, outlets and appliances should be labelled or tagged in accordance with WRAS Guideline IGN 9-02-5. For example, labels should be applied to the back of a washing machine or inside the lid of a WC cistern.
BRE Environmental Assessment Method (BREEAM) – not a legal thing but rather a recognised assessment method that applies to sustainable construction of commercial properties. See the website for more information.
The above are the relevant governance instruments at time of writing. It is incumbent on all operators and their employers to check for recent additions and changes.
Find Out More
Feel free to contact us for advice on any aspect of the regulatory aspects of rainwater harvesting systems and installations. To find out more about rain water harvesting systems in general, please download our Ultimate Guide To Rainwater Harvesting Systems, a free e-book that explains the different types of rain collection system that can be used on domestic and commercial properties. Access a free copy by clicking here. Call our office on 01452 772000, or email