Treatment options to improve drinking water quality 

If your test results highlight a health or quality issue in the water coming from your well or small private group scheme, you have a number of options  – depending on the type and source of contamination. Moreover, you may be eligible for a grant towards the costs of the some of these options.

Contamination with microbes (bugs)

If your drinking water is contaminated with microbes (bugs, bacteria, germs) the water should be boiled until it is safe to drink. Your next steps may then include

  • Short-term chlorination – Chlorine (e.g. dilute Milton) is the most commonly used disinfectant in Ireland. However, it is only suitable as an occasional treatment option as opposed to being used on an on-going basis.  Chlorination protects against pathogens but not against Cryptosporidium.
  • A better long-term option is to address the sources of contamination by ensuring your well is properly located, constructed and maintained. This guide, available from the EPA website, contains advice.
  • If your well is located too close to a polluting activity – or if the water is still contaminated after you have taken steps to protect it – you might consider UV treatment.  If used correctly, ultraviolet (UV) light is very effective against pathogens and Cryptosporidium. However, it will only work if the water is clear and contains low levels of iron and manganese, which can cause fouling of the UV lamp.


Lead is a serious toxicant. If lead piping is present in your water supply system, you should have it removed and replaced with new piping.

Ammonia, nitrite and nitrate

Elevated levels of ammonia, nitrite and nitrate make water unsafe to drink and may occur as a result of run-off from agricultural slurry, fertiliser or industrial waste. As highlighted above, this guide provides advice on correct well location, construction and maintenance to prevent effluent contamination.  If these efforts fail, nitrates can be removed through the installation of a Reverse Osmosis (RO) system.

Hard water

If you are concerned about hard water causing damage to appliances, you might consider installing a water softener system.  In most cases, these work by adding salt  to remove the hardness.  Water softened in this way can be used for showering and washing. However, the softening system should bypass the  kitchen tap used for drinking and cooking. This is important because too much salt can be a problem for premature babies and people who are on a low sodium diet.  Additionally, artificially softened water may also be aggressive to plumbing, causing leaching of copper and lead.

If you decide to install a water softener, it is  important to purchase from a reputable supplier and have it installed by a qualified plumber.

High acidity (low pH) and corrosion

High acidity can cause leaching of copper and zinc from your piping/plumbing system. Where excessive corrosion is present, you may have to replace your copper piping or hot water cylinder.  If your water has a low pH (acidic), you may consider installing a neutralisation system as a preventative measure.

Iron & manganese causing staining/discolouration

Slightly elevated levels of iron and manganese are not thought to have negative health impacts. However, their presence in drinking water can cause severe discolouration, and manganese can also cause an objectionable taste. Treatment systems, such as oxidation, can be used to remove iron and manganese.


Different types of jug/cartridge filters can remove certain substances,  leading to improved water taste and appearance. However, you should be aware that colour or cloudiness in water could be a symptom of other problems such as the presence of organic matter or ineffective disinfection.

Any treatment system installed should be maintained and operated in accordance with the manufacturers specifications – or it may not do the job intended and could, in fact, pose a risk to your health. This guide from the UK Drinking Water Inspectorate provides useful information about cautions related to filtration systems. 

Serious and persistent water quality issues

If you are experiencing serious and persistent water quality issues,  you might  consider being connected to a nearby public or group water scheme (if possible). Further information about getting connected to the public network  is available on the Irish Water website.

To find out more about having your water supplies tested, visit our water analysis page or call us on 059 91 52881.