WaterSafe Approved Plumbers Supply Pipe Contractors

The Water Supply (Water Fittings) Regulations 1999 set national standards for the design, installation and maintenance of plumbing systems connected to the public water supply. Their purpose is to prevent contamination, waste, misuse and incorrect installation that could affect drinking water quality.

Water companies have legal duties under the Water Industry Act 1991 (sections 73, 74 and 75) to enforce these regulations and protect public water supplies. These provisions give water companies the power to ensure that plumbing systems connected to the public supply comply with the Water Fittings Regulations. For this reason, plumbing work connected to the mains water supply must comply with the Water Fittings Regulations.

A Water Regulations Approved Plumber is a contractor assessed through a recognised approval scheme such as WaterSafe and authorised to work on all plumbing systems connected to the public water supply.

This includes plumbing inside a property as well as external pipework connected to the mains water supply.

Approved plumbers demonstrate competence in applying the Water Supply (Water Fittings) Regulations 1999 and can certify that installations comply with those regulations.

An Approved Supply Pipe Contractor (or Supply Pipe Installer) is approved to carry out work only on the external supply pipe. Their scope of approval is limited to the pipe that runs from the water company communication pipe at the property boundary up to the internal stop valve inside the property.

Unlike approved plumbers, they are not approved to work on internal plumbing systems, and their approval is limited to underground supply pipe installation and repair.

Using an approved contractor helps ensure work connected to the public water supply is carried out correctly and in accordance with the Water Supply (Water Fittings) Regulations 1999. Water companies have legal duties under the Water Industry Act 1991 (including sections 73–75) to protect the public water supply and enforce the Water Fittings Regulations.

Approved plumbers and approved supply pipe contractors have demonstrated knowledge of the regulations and understand water company requirements when carrying out installations or repairs.

Yes. Water companies have the legal power to inspect plumbing systems connected to the public water supply to ensure compliance with the Water Supply (Water Fittings) Regulations 1999.

Inspections may occur where there is a suspected risk to water quality, when new connections are installed, or when complaints or issues are reported.

Using an approved plumber or supply pipe contractor helps reduce the need for inspections because the work can often be certified as compliant.

Water companies have powers under the Water Industry Act 1991 (sections 73–75) to investigate plumbing installations that may breach the Water Supply (Water Fittings) Regulations.

If a plumbing system is found to be non‑compliant, the water company may issue an enforcement notice explaining what needs to be corrected and the timeframe within which it must be done.

In serious cases where there is a risk to public health or the water supply, the water company may take further action until the installation is brought into compliance.

When regulated plumbing work is carried out by an approved contractor, the installer can issue a Certificate of Work Completed confirming the installation complies with the Water Supply (Water Fittings) Regulations 1999.

This certificate confirms that the work has been carried out by a competent approved contractor who understands and applies the requirements of the Water Regulations.

Under the Water Industry Act 1991 (sections 73–75), water companies have powers to investigate, issue enforcement notices, and prosecute where plumbing installations connected to the public supply breach the Water Fittings Regulations. In those circumstances, a Certificate of Work Completed issued by an approved contractor is the primary evidence available to a property owner that the installation was carried out in compliance with the Regulations.

For property owners, keeping this certificate is important because it can be relied upon as evidence of compliance and the only practical defence available if enforcement action is taken in relation to the plumbing installation.

The pipe which connects the water main in the street to your property is known as the service pipe and is divided into two sections.

The section of pipe that runs from the water main in the street to the outside stop valve (normally located at the property boundary) is called the communication pipe and is the responsibility of the water company.

The section of pipe that runs from the outside stop valve or property boundary to the internal stop valve inside the property is known as the supply pipe and is normally the responsibility of the property owner.

All plumbing within the property beyond the internal stop valve is also the property owner's responsibility. Supply pipes may either be separate (serving one property) or shared between two or more properties, which is common in older terraced houses.

Properties built before around 1970 may still have lead supply pipes. Replacing these pipes is often necessary to improve drinking water quality and may also allow homeowners to apply for the water company's lead pipe replacement scheme.

Approved plumbers can replace internal lead pipework and certify that the installation complies with the Water Supply (Water Fittings) Regulations 1999, while approved supply pipe contractors can install or replace the underground supply pipe from the property boundary to the internal stop valve. Using approved contractors helps ensure the work can be certified as compliant and coordinated correctly with the water company.

If a leak is identified on the private supply pipe, the water company may issue a customer‑side leakage notice requiring the property owner to repair or replace the leaking pipe within a specified timeframe. These notices are typically served when water is being lost from the private supply pipe between the property boundary and the internal stop valve.

Approved plumbers and supply pipe contractors are specifically qualified to investigate and repair these leaks. Once the work is completed, they can provide certification confirming the installation complies with the Water Fittings Regulations, helping demonstrate that the problem has been resolved in accordance with water company requirements.