Works on-going to address water discolouration issues in Dundalk

18 June 2021

Irish Water, working in partnership with Louth County Council, are continuing with works to restore normal water supply to some customers in Dundalk impacted by discoloured water. Irish Water and Louth County Council investigated the matter and found a large burst on the network caused sediment to be dislodged and carried through the network to the customer tap. Following the successful completion of repairs some customers continued to experience discoloured water.

Irish Water and Louth County Council undertook a programme of further investigations, which included monitoring at various locations throughout Dundalk town, and found that the build-up of sediment and the subsequent discolouration of water at customer taps was caused by the presence of manganese, a mineral which occurs naturally in the area. Manganese is found naturally in many surface water (lake and river water) and groundwater (underground water) sources, including the River Fane, which is the source water for the Cavanhill Water Treatment Plant.

In response to this issue, a programme of works is currently taking place at the Cavanhill water treatment plant to reduce manganese levels in the final treated water, and therefore reduce the likelihood of sediment build-up in the network. Following completion of the works at Cavanhill Water Treatment Plant, we intend to conduct a network flushing programme in Dundalk town and environs to clear the network of any remaining sediment. We will advise customers in advance of when we intend to commence this activity.

While we complete these essential works and further monitoring of the network, customers are advised that if their water is discoloured, to continue running the tap for a few minutes to restore the clear colour. If the colour does not restore to clear, customers are advised not the drink the water as a precaution, and should contact Irish Water using the contact details below.

Irish Water can confirm that the Manganese levels found during our investigations are not at a level that would pose a risk to health, however we are continuing with enhanced monitoring both at the plant and in the network to keep the situation under close review. In this regard we have been consulting with the Health Services Executive (HSE), who are the statutory authority in public health matters. If the situation changes, and a risk to public health arises, we will notify all affected customers immediately.

Irish Water apologises for any inconvenience as a result of this issue.

For more information on issues in drinking water, customers can visit the Supply and Service Updates section of our website. Information on drinking water quality can be found in our drinking water quality section. The HSE have also produced an informative Frequently Asked Questions on Manganese in drinking water which can be found here (FAQ).

Customers with queries or concerns about the quality of their drinking water should contact the Irish Water customer care helpline, open 24/7 on 1800 278 278 or via Twitter @IWCare.

Irish Water continues to work at this time, with our local authority partners, contractors and others to safeguard the health and well-being of staff and the public and to ensure the continuity of drinking water and wastewater services. Irish Water would like to remind customers to follow the HSE COVID-19 advice on handwashing.

Previous Updates

Irish Water is aware of a number of reported issues from customers in Dundalk regarding discoloured drinking water. Irish Water and Louth County Council investigated the matter and found a large burst on the network caused sediment to be dislodged and carried through the network to the customer tap. Repairs were completed on Friday 11 June but some customers continue to experience discoloured water.

Irish Water and Louth County Council undertook a programme of further investigations, which included monitoring at various locations throughout Dundalk town, and found that the build-up of sediment and the subsequent discolouration of water at customer taps was caused by the presence of manganese, a mineral which occurs naturally in the area. Manganese is found naturally in many surface water (lake and river water) and groundwater (underground water) sources, including the River Fane, which is the source water for the Cavanhill Water Treatment Plant. In response to this issue, a programme of works is currently taking place at the Cavanhill water treatment plant to reduce manganese levels in the final treated water, and therefore reduce the likelihood of sediment build-up in the network. Following completion of the works at Cavanhill Water Treatment Plant, we intend to conduct a network flushing programme in Dundalk town and environs to clear the network of any remaining sediment. We will advise customers in advance of when we intend to commence this activity.

While we complete these essential works and further monitoring of the network, customers are advised that if their water is discoloured, to continue running the tap for a few minutes to restore the clear colour. If the colour does not restore to clear, customers are advised not the drink the water as a precaution, and should contact Irish Water using the contact details below.

Irish Water can confirm that the Manganese levels found during our investigations are not at a level that would pose a risk to health, however we are continuing with enhanced monitoring both at the plant and in the network to keep the situation under close review. In this regard we have been consulting with the Health Services Executive (HSE), who are the statutory authority in public health matters. If the situation changes, and a risk to public health arises, we will notify all affected customers immediately.

Irish Water apologises for any inconvenience as a result of this issue.

For more information on issues in drinking water, customers can visit our Water Supply section. Information on drinking water quality can be found in our drinking water quality section. The HSE have also produced an informative Frequently Asked Questions on Manganese in drinking water which can be found here (FAQ).

Customers with queries or concerns about the quality of their drinking water should contact the Irish Water customer care helpline, open 24/7 on 1800 278 278 or via Twitter @IWCare.

Irish Water continues to work at this time, with our local authority partners, contractors and others to safeguard the health and well-being of staff and the public and to ensure the continuity of drinking water and wastewater services. Irish Water would like to remind customers to follow the HSE COVID-19 advice on handwashing.