Drinking Water Quality

The EPA Drinking Water Report for Public Water supplies 2015 provides an overview of drinking water quality in Ireland for 2015, based on monitoring data from Irish Water, and the regulation of public supplies by the EPA.  A separate report is being prepared to provide information on the quality of drinking water in private water supplies.  

Drinking Water Report 2015

Quality of Supplies

The safety of public water supplies in Ireland is determined by comparing the results of over 185,500 monitoring tests against the parametric limits set out in the Regulations.

On water supply safety, the EPA found that in 2015:

  • E. coli compliance in Public Water Supplies continues to improve.  Since 2007, there has been an 86.5% reduction in the number of public water supplies reporting E. coli exceedances. E.coli was detected at least once in 7 supplies, down 1 on 2014.
  • Trihalomethanes compliance in public water supplies increased from 90.7% in 2014 to 91% in 2015.  Trihalomethanes limit was exceeded in 59 supplies the same as 2014. 
  • 35 Boil Notices and 9 Water Restriction Notices were issued, affecting 47,271 people.     

Remedial Action List for Public Water Supplies

The EPA’s Remedial Action List (RAL) is a register of public water supplies with the most serious deficiencies and known to be most at risk, where the EPA is requiring Irish Water to take corrective action to ensure the safety and security of the supplies.  The EPA has instructed Irish Water to submit an action programme for the improvement of each of these water supplies and has initiated enforcement action where action programmes have not been prepared or implemented to the satisfaction of the EPA.  This includes issuing legally binding Directions requiring specific work to be carried out to ensure the safety and security of a water supply.

Since the original RAL was published in 2008, 82% (277) of supplies have been removed from the original list because the necessary remedial actions have been completed.  The primary issues addressed to-date include disinfection of E. coli, barriers to Cryptosporidium, adequate treatment for trihalomethanes and operational controls for managing aluminium and turbidity levels.  The EPA updates and publishes the RAL on a quarterly basis.  99 supplies remain on the RAL at the end of December 2016 which collectively supply water to 774,340 consumers.

The interactive map below shows the location of the 99 water supplies on the RAL at the end of December 2016. Alternatively, view the current Remedial Action List. 

Click on a red dot to find out more information about these supplies including the reason the supply is on the RAL and the anticipated completion date for the remedial works.


Regulation of Public Water Supplies

The EPA issued 31 legally binding Directions to Irish Water in 2015.  The total number of Directions issued during 2015 increased from 29 in 2014.  The Directions require specific actions to be undertaken to improve the security of the relevant public water supplies.  Directions were issued due to Trihalomethanes exceedances in 9 supplies.  6 Directions were issued due to adequate responses by Irish Water to EPA Audit Reports.    

Water Safety Plans

A supply is deemed 'safe' if it meets the relevant drinking water quality standards at the tap and 'secure' if a management system, a Drinking Water Safety Plan (DWSP), is in place that identifies all potential risks and procedures to manage these risks.  In 2009 the World Health Organisation (WHO) published detailed guidance on the implementation of the Drinking Water Safety Plan approach, the document is entitled "Water Safety Plan Manual: step-by-step Risk Management for Drinking Water Supplies".  The primary objective of this approach is to protect human health.  The approach applies equally to small and large drinking water supplies.

The EPA has adopted the WHO's water safety plan approach (see Advice Note No 8).  The advice note is intended to give an overview of the steps involved in constructing a DWSP and an outline of what is should contain.  It contains guidance on hazard identification, risk assessment and the preparation of action plans for hazards identified.  It is aimed at all staff involved in the production and distribution of drinking water and should be read in conjunction with the WHO guidance manual.  DWSPs are also covered in Section 10 of the EPA's 2010 Handbook for Public Water Supplies.

In 2014 the EPA launched a DWSP online tool.  This online tool (see Environmental Data Exchange Network (EDEN)) is to be used by Irish Water and Local Authority staff in the completion of DWSPs.  6 DWSP plans have been completed and 53 are in preparation.

Priority Actions

The EPA has addressed the following recommendations, in relation to Public Water Supplies, to Irish Water:

  • Eliminate long-term Boil Water Notices by improving disinfection standards.
  • Implement the National Lead Strategy.
  • Optimise chemical dosing and improve treatment to reduce THM exceedances.
  • Priortise RAL schemes for improvement/investment.
  • Protecrt sources and abstraction points.
  • Develop Drinking Water Safety Plans.

Completing the remedial action programmes, improving controls on chemical dosing, source protection and compliance with the Good Agricultural Practice regulations will help improve the resilience of our water supplies.  In addition, applying the water safety plan approach will provide an integrated way to manage risks associated with drinking water supplies from catchment to consumer into the future.

Owners of private wells should ensure that they are designed, located, installed and maintained properly.  Wells should be tested regularly, particularly after a prolonged period of heavy rainfall, since this is when the well may be overwhelmed and contaminated.

Find out more

Download drinking water datasets (Look for drinking water monitoring results and water supply details for Ireland in the list)