Private water supplies are sources of water that are owned and managed by individuals or households, rather than by a public utility. According to the UK Drinking Water Inspectorate (DWI) approximately 3% of the population in England and Wales receive their water from private supplies and approximately 5% of the population of Scotland. These water sources can vary greatly both in water quality and how they are treated, below we’ve listed some of the most common forms of private water supplies. 

• Wells: A well or borehole is an excavation that is dug or drilled into the ground to access underground water sources. Such as aquifers or underground streams.
  
  
• Springs: A spring is a natural source of water that emerges from the ground. Springs can be found in a variety of landscapes, including mountains, valleys, and plains.
  
  
• Rainwater Harvesting: Rainwater harvesting is the process of capturing and storing rainwater from roofs or other surfaces for later use.
  
  
• Surface Water: Surface water sources are bodies of water, such as lakes, rivers, and streams, that are located at surface level.

It is important that water from these sources are tested regularly to ensure that any contaminants that fall outside of acceptable limits are treated. Contaminants such as bacteria and chemicals can enter the water supply through a variety of sources. These include surface runoff, animal waste and faulty septic systems. Proper treatment and management of a private water supply is vital to ensure that the water is safe and clean for general use or consumption.

What Water Treatment Is Used For Private Water Supplies?

There are several methods used to treat water from a private water supply. These methods may be used individually or in combination, depending on the specific contaminants present in the water and the desired level of treatment. Where water is being consumed from a private supply, it needs to be tested regularly to ensure that it is safe to drink and that any treatment in place is working effectively.

The most popular methods of water treatment for Private Water Supplies include:

Filtration: This process involves passing the water through a filter to remove suspended particles like dirt, silt, rust and sand. There are many technologies that can be used including cartridge filters, bag filters and filter beds which use layers of sand or gravel to remove sediment.

Disinfection: Disinfection is the process of killing or inactivating pathogenic (disease-causing) microorganisms in the water. Chlorine and ultraviolet (UV) light are common disinfection methods used for private water supplies.

Reverse Osmosis: Reverse osmosis is a process that removes contaminants from water by forcing it through a semi-permeable membrane. This process is effective at removing a wide range of contaminants, including dissolved salts and heavy metals.

Water Softening: This process usually uses an ion-exchange water softener to remove hardness from water and prevent limescale formation in pipework and appliances. Water softeners also remove low levels of iron and manganese, however for high levels of these contaminants a specialist treatment system should be employed.

Iron & Manganese Removal: The use of backwashing systems containing specialist iron and manganese removal resin is recommend for water where these contaminants fall outside of acceptable limits. These systems oxidise the iron and manganese to form a precipitate and hold on to it until the system is backwashed, when it is sent down the drain.  

pH Correction: pH correction is important where water has a low pH and has the potential to corrode pipework. pH can be corrected using an alkaline media (such as calcium carbonate) to increase the pH of the water.

Why Are UV Systems Used For Water Treatment?

UV treatment is an effective and environmentally friendly method of disinfecting water, as it does not generate any harmful by-products or leave any residuals in the water. UV sterilisation uses a ‘reactor chamber’ to pass water along a UV lamp which emits ultraviolet light. The natural properties of UV light disrupts the DNA of any micro-organisms in the water. This destroys their ability to function normally and reproduce – in turn stopping them from being able to make you unwell.

UV systems are typically easy to maintain, as they do not require the use of chemicals and do not generate any hazardous waste. Regardless of whether a water analysis report shows bacteria in a private water supply, it is always recommended to treat the water with a UV system. This is because without biocides like chlorine, bacteria can build up quickly in tanks and pipework.

How Much Does Water Treatment For A Private Water Supply Cost?

The answer to this question depends on what contaminants are highlighted in your water analysis and what you plan on using the water for. For example, if you are only using the water for plants in your garden, then it is likely that less treatment would be required than if you wanted to drink the water.

If Your Water Falls Within The Acceptable Limits For Drinking
If your water analysis already falls within the acceptable limits for drinking, then a basic treatment system comprising of a sediment filter or a series of sediment filters and a UV system would be recommended. For a supply that feeds a single dwelling, a treatment system such as this would usually cost between £500 and £800 depending on the size of the property.

If Your Water Falls Outside Of The Acceptable Limits For Drinking
If you have other contaminants in your water such as iron, nitrates or manganese that fall outside of the acceptable limits for drinking water, additional stages of filtration should be employed to remove or sufficiently reduce them. Private supplies that are made available for the public to drink may need more advanced equipment, which allows for remote monitoring or automatic shut off if there is an issue with the system. In these instances treatment systems will include sediment filtration and UV disinfection as a minimum. The cost of any additional stages depends on the flow rate and the amount of treatment that is required. 

Keeping Your Private Water Supply Compliant

Private water supplies are increasing in popularity in the UK, as water bills rise and people move out of cities to more rural areas without access to a mains supply. The most important thing is to ensure your private supply is regularly tested and that any water treatment equipment in place is well maintained. If you have a property with a private supply where commercial activity takes place, or where the water is made available to the public for drinking, then additional regulations may apply. Be sure to check the DWI regulations to ensure your private water supply is compliant.  

The amount of treatment that water from a private supply requires depends on the water analysis. Private water supplies should be registered with your local council who will ensure that it is tested at the recommended intervals. It is important to note that environmental health may take action where they find a contaminated supply, which can include giving notice not to consume the water.

We have years of experience when it comes to the treatment of Private Water Supplies. If you have a water analysis that you would like to discuss or are considering buying a property with a private water supply and want to find out more about what is involved, feel free to get in touch with a member of our team.