Private Water Supplies

A private water supply is any water supply which is not provided by a water company, such as Dwr Cymru/ Welsh Water. It is not a ‘mains’ supply and is therefore private.  The source of the supply may be a spring, well, borehole or surface water (streams, lakes, etc.).  A supply may serve a single dwelling, several properties or commercial or public premises.

A private water supply could serve just one dwelling, be shared amongst several properties or it could be a large or commercial supply with a network of pipes supplying water to many properties. It also includes a supply provided for the purpose of bottling water.

All private water supplies in Wales are regulated under the Private Water Supplies (Wales) Regulations 2017 The Regulations have been introduced to ensure that water from private supplies is wholesome, so that people who drink water or consume food or drinks made from private supplies may do so without risk to their health.

These regulations require Local Authorities to;

• Undertake a risk assessment of all shared water supplies, supplies to tenanted properties and commercial supplies every 5 years and to respond to any request for a risk assessment by the owners or occupiers of a single dwelling.
• Monitor all shared/tenanted supplies and commercial supplies in accordance with the sampling frequencies specified and to respond to any requests by owners or occupiers of single dwellings.
• Keep records of all private water supplies in its district and to supply a report of activities undertaken to the Drinking Water Inspectorate (DWI).
• Follow set procedures if we consider a private water supply to be unwholesome or a potential danger to human health.

For information on Private water supply fees and charges.

If you are concerned about the quality of water supplied to your property from a private water supply, you can contact the Environmental Health Team to test a sample of the water. Be advised that Merthyr Tydfil County Borough Council may charge you for this service. Even if there is a problem with the quality of your supply, there are a variety of treatment methods available to deal with most circumstances.

Issues and actions

If a problem with the quality of your supply discovered, we can advise you of the variety of treatment methods available to deal with most circumstances. You are responsible for selecting an option, arranging and paying for the works required.

If you have a private distribution of supply to a commercial premises and you choose not to do the works that is advised of you then, there are other actions that may be taken via the Regulations, including the serving of notices.

Common problems with private supplies

Private water supplies are often polluted with bacteria known as coliforms. If these bacteria are found in your water it means that the supply is being polluted somewhere between the source and your tap. This can be caused by animal waste or sewage which comes into contact with the water.

The land that the source of your supply is on can cause the water to pick up naturally occurring metals. For example, acidic water coming from peat moorland can pick up aluminium and manganese. Acidic water can also corrode copper and lead pipes.

Water could be polluted by normal agricultural practices such as spreading farm sludge, or by fertilizers running off the land or by percolating through the soil into the water. Septic tanks, manure heaps and drains can all cause pollution as well as animals getting access to the supply.

What you can do to improve your supply

• Fencing off a spring chamber to stop animals entering and contaminating the area;
• Creating an exclusion zone for the spreading of fertilizers around the spring or well;
• The improvement of drainage around to supply; or
• The replacement of pipework.

Sometimes it may prove necessary to install a filter to remove or lower the level of a particular substance. These can include:

• Ultra-Violet filters to remove bacteria (E. Coli)
• Reverse Osmosis filters to remove aluminium or nitrate
• Iron and Manganese filters
• Cation Exchange filters to remove lead

Further information

For further information on Private Water Supplies, contact the Environmental Health Team on 01685 725000