If you’re planning any changes to your plumbing at home, you may need our permission before you start. 

The Regulations


The Water Supply (Water Fittings) Regulations 1999, England and Wales, require you to notify us if you’re making alterations to your water systems. They apply to all plumbing within the boundary of your home or business building and to appliances connected to the water supply.

They’re designed to not only prevent water contamination, misuse, waste and excessive consumption, but safeguard against wrong usage readings and keep our drinking water safe.

Notify us if you’re planning to:

  • build a house or other property/structure
  • install a swimming pool or pond over 10,000 litres
  • install a bidet with an upward spray or flexible hose
  • set up a garden watering system (unless operated by hand)
  • set up a reverse osmosis unit (for cleaning water)
  • install a water treatment unit which produces wastewater
  • install a  bath which holds more than 230 litres of water
  • use a reduced pressure zone  valve assembly or similar
  • install a pump or booster drawing more than 12 litres of water per minute
  • use any water system outside a building which is either less than 750mm or more than 1,350mm below ground
  • change the use of a building or install systems such as rainwater harvesting
  • extend or altering the water system on a business building.

Getting approval

It’s the legal duty of the owner, occupier, installer or plumber to follow the Regulations and notify us before the work begins.If the owner or occupier doesn’t seek permission, the duty rests with the installer or plumber.


Getting our approval is easy, all we need is:

  • your name, address and contact details
  • a description and location of the proposed work
  • the plumbing contractor’s name and address if one  is being used.

We may ask for additional information such as a list of water fittings and evidence of compliance with the Water Supply (Water Fittings) Regulations.

Failure to notify us could result in prosecution or the need to carry out costly extra work at a later date. Use our online form to get approval.

Using an approved plumber

An approved plumber is trained to work safely with drinking water and can undertake some plumbing jobs without having to notify us. Once the work’s completed, the plumber will issue a certificate confirming it meets the regulations. To find an approved plumber near you, go to the WaterSafe website and put in your postcode.

Starting work

You can start work once you’ve received permission from us. We’ll normally let you know within 10 working days, but if you haven’t heard within this time, assume you’ve consent and begin.

Your plumbing work must still comply with the Regulations. If it doesn’t, you may need to make changes later.Below are some examples where plumbing failed to meet the regulations: 

  • This waste water pipe was left with no end fitting, risking contaminants or even animals/insects travelling back up to the main water supply. Once we highlighted the problem, our customer installed a standpipe and tap – easily solved! 

  • A homemade bidet with the shower head next to the toilet. If the shower head was submerged in the toilet it posed a risk of back siphoning. We asked for the whole connection to be removed. 

  • Here’s some risky pipework exposed to the elements and connected to a storage tank with nothing preventing the water backflowing into the mains supply. All pipework should be buried to prevent frost damage and the tank needs a backflow inhibitor. 

  • Shop fitters installed this temporary water supply to a business in Milton Keynes, bypassing their water meter and using a supply designated for the fire service. The connection used piping of differing sizes and materials, posing a high leakage risk and a potential problem for the fire service. The installers were successfully prosecuted and ordered to pay full costs. 

  • When investigating a drinking water monitoring failure, we found illegal lead soldering had taken place when installing the pipework. The lead affected the drinking water quality and consequently, all the pipework was removed and reinstalled at the property owner’s expense. 

Find out more about the regulations.

Further information