Lough Talt Water Supply Plant Upgrade, Sligo


The Lough Talt water treatment plant (WTP) did not provide adequate treatment and needed to be upgraded. The water supply is included on the EPA’s Remedial Action List (RAL) as the WTP did not provide sufficient protection against cryptosporidium or formation of trihalomethanes (THM).

It supplies Tobercurry and Ballymote and surrounding communities including Annagh, Aclare, Bellaghy, Curry, Lavagh, Ballinacarrow, Carrowneden, Kilmacteige and Coolaney, Cloontia, Doocastle and Quarryfield.

In May 2019, Irish Water was granted planning permission to upgrade the WTP. Irish Water is now working with Sligo County Council to upgrade the plant. Once complete, the new plant will provide safe drinking water for the next 10 years, and will allow the Boil Water Notices to be lifted. The long term solution is to provide water from an alternative source. This is being investigated by Irish Water while we complete upgrades to the existing Water Treatment Plant.

The upgrade project will involve:

  • Addition of new containerised process units
  • Construction of new water tanks
  • Construction of a new entrance onto the R294
  • Landscaping, habitat compensation and ancillary works

The Lough Talt Water Treatment Plant treats 8 megalitres of drinking water per day, and “off the shelf” mobile filtration plants are not available at this scale. The proposed treatment for Lough Talt will use prefabricated containerised treatment units.

RPS Group works

Preparation of a Water Abstraction Order for Lough Talt in 2010 to regularise the abstraction ongoing for over 70 years. Lough Talt is designated as part of the Lough Hoe Bog Special Area of Conservation (SAC) and the River Moy SAC.

Due to environmental sensitivities, carried out detailed hydrological and geological investigations between 2012–2016 to assess the potential impact of the existing abstraction on the integrity of the European sites’ conservation objectives.

Found that during periods of extended dry weather the lake level drops as a result of the abstraction operation, which impacts the Lough Hoe Bog SAC, potentially endangering the protected Geyer’s whorl snail.  

To avoid the impact the abstraction needed to reduce by approximately 50% during a significant portion of the year (approximately 95 days).

This would not be adequate to supply the existing population requiring a supplementary water supply.

Based on the studies and reporting prepared by RPS, Sligo County Council completed the Appropriate Assessment.

An assessment of solutions showed no available alternative options to supply safe drinking water in the short to medium term. Consent was granted for IROPI to address the ongoing contamination and public health risk.

Based on the documents prepared by RPS, including IROPI and compensatory measures, a statement of case was prepared for consideration by the government.

The compensatory measures including the reintroduction of the whorl snail were accepted by the Minister for Housing, Planning and Local Government and Minister for Culture, Heritage and the Gaeltacht as being sufficient to safeguard the protected site.



Leave a Reply