Planning Some Plumbing? Know the 'Water Law'

WaterSafe is urging anyone planning plumbing work to make sure they know the `water law’ before they start.

In many cases, work on new and existing plumbing systems, and some types of water installations, needs to be notified to, and approved by, the local water supplier before it can begin.

This is to make sure it meets the Water Supply (Water Fittings) Regulations and Byelaws that are designed to keep drinking water supplies safe and healthy.

The warning doesn’t just apply to plumbers either - businesses, homeowners, landlords and tenants all need to follow the regulations too.

Julie Spinks, director of WaterSafe, said: “UK homes and businesses enjoy high-quality, safe drinking water and it is important it stays that way.
“Unfortunately very few people are aware of their legal responsibilities to ensure certain types of plumbing work complies with these important regulations.
“Getting permission is quick and free, but failure to notify the local water supplier could result in extra cost to put poor plumbing right or, worse, contamination of water supplies and a court prosecution.
“We are delighted to back the campaign by the Water Regulations Advisory Service (WRAS) which has a simple message at its core - if you are planning some plumbing installation work, take a few minutes to seek professional advice.”

The regulations apply to many types of domestic and commercial plumbing – from building new houses or extending business premises to everyday work such as installing certain types of bidets or large baths.

Types of plumbing work that must be notified to the local water supplier includes:

  • Building a house or other property/structure
  • Extending or altering the water system on a non-household building
  • Changing the use of a building or installing water systems, such as rainwater harvesting
  • Installing a swimming pool or pond over 10,000 litres
  • A garden watering system (unless operated by hand)
  • A bath which holds more than 230 litres of water
  • A bidet with an upward spray or flexible hose
  • A pump or booster that delivers more than 12 litres of water per minute
  • A reverse osmosis unit (for cleaning water)
  • A water treatment unit which produces waste water
  • A reduced pressure zone (RPZ) valve assembly or similar
  • Any water system outside a building that is either less than 750mm (0.75 metres) or more than 1350mm (1.35 metres) below ground.

  • This list is not exhaustive and there are extra requirements in Scotland and Northern Ireland.

    WaterSafe approved plumbers – who are already trained to meet the strict regulations for installing pipes and fittings which supply drinking water – are able to carry out some types of work without prior notification.

    WaterSafe is the central body for approved professional plumbers in the UK and accredited businesses can be found using the postcode search at

    Our Partners

    WaterSafe Approved Contractors' Scheme Operators

    Anglian WaterAssociation of Plumbing & Heating ContractorsCIPHESevern TrentSNIPEFWIAPS

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