There are potentially many products and substances, in use within private supply systems which will come into contact with water that is intended for domestic purposes, from the point of abstraction to the point of consumption. These can include:
- the surfaces of pipes
- treatment chemicals or filter media
- point of use devices
- water fittings such as components of meters, pumps, and valves
It is therefore important that these products or substances do not have a detrimental effect on the quality of the water or cause a risk to public health. This is implemented through Regulation 5 (Regulation 5 Wales) of the Private Water Supplies Regulations.
It is essential that the design of any treatment process is based on a full investigation of site conditions, including chemical and microbiological analysis of the water to be treated, a risk assessment and the results of laboratory or pilot scale tests to determine not only the effectiveness of the process and any chemical dosing requirements, but whether the system is adequate for the volume of water that will be treated.
There have been a number of water quality issues associated with unapproved products and the Inspectorate has made available a number of different Case Studies in order to provide additional guidance for local authorities and relevant person(s).