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Water Services

Drinking Water Quality


Ireland is fortunate to have safe and reliable sources of fresh, raw water that we can treat and use as drinking water. However, there are many different factors that can have an impact on the quality of drinking water, for example soil or rock types, land use practices and even high rainfall can all affect the quality of drinking water.

When we turn on the tap, we all expect to be assured of clean, safe drinking water being delivered to our homes and businesses every day and it’s important to remember that there is a complex process behind the treatment, monitoring and testing of our drinking water in Ireland.

Drinking Water Monitoring Programme

Under the European Union (Drinking Water) Regulations 2023, Mayo County Council is responsible for drawing up and executing a drinking water monitoring programme for all regulated private supplies within its functional area.

Mayo County Council procure appropriate sampling and testing services to carry out the monitoring programme for regulated private supplies, in accordance with the Regulations. These services are also employed to carry out any additional sampling required on private supplies (regulated or exempt) throughout the year.

Drinking water parameters are tested to ensure that the drinking water quality is of an acceptable standard, as set out in the European Union (Drinking Water) Regulations 2023.

Drinking water parameters are grouped into 3 categories:

  • Indicator parameters are usually tested along with microbiological and chemical parameters in a water sample. These parameters may not necessarily pose a risk on their own, but they can indicate the presence of other potentially more harmful parameters in a water sample.
  • Chemical parameters are tested in drinking water samples to determine if any chemicals present are within acceptable limits. Chemical parameters that are present in drinking water samples can be caused by chemicals dissolving into water from pipes, chemicals carrying over from water treatment processes, chemical reactions that can occur between different materials in the water, or even runoff from farms.
  • Microbiological parameters are microorganisms (i.e. bacteria) that are tested in drinking water. The presence of these parameters in a drinking water sample may indicate that contamination may have occurred either at a water source or within the water distribution network.

Water quality test results can be obtained on request from the rural water office, please see contact details below.

Boil Water Notice

A drinking water exceedance occurs when a parameter value is above the acceptable limit. When an exceedance occurs, steps are taken in line with the Regulations, to ensure mitigation and remedial action takes place swiftly to minimise effects.

In some instances, a private supply will be issued with a Boil Water Notice. A register of Boil Water Notices can be viewed and is available for download by clicking Rural Water - Boil Water Notice Register.

Any further queries in relation to drinking water quality on a private supplies can be made by emailing ruralwater@mayococo.ie or by contacting the rural water office on 094-9064000.

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