Irish Water is progressing with its work on a number of €multi-million Water Treatment Plant upgrades aimed at ensuring their removal from the Environmental Protection Agency's (EPA) Remedial Action List (RAL).

Upgrades to Mayo water treatments plants which supply over 46,000 people whose water supplies are on the RAL.on schedule to be completed by end of 2017

There are currently four schemes on the RAL in Mayo - the Ballina-Lisglennon and Inisturk schemes remain on the RAL for elevated levels of THMs and Irish Water expects works to be completed on these schemes by the end of 2017. The utility is currently upgrading the Ballina-Lisglennon water treatment plant and works include optimising the process and upgrading the disinfection system. At the Inishturk Water Treatment Plant the disinfection system is currently being upgraded and other works to eliminate THMs are planned.

There are two other water supplies in Mayo on the RAL - Kiltimagh and Lough Mask Water Treatment Plants and specific work improvements to both processes are underway. At Kiltimagh water treatment works, the disinfection system is being upgraded and the water treatment process optimised. At Lough Mask water treatment works a €1.6m project to improve the treatment process is underway with an expected completion date of August 2017.

Irish Water has put in place the first national Trihalomethanes (THM) plan and a prioritised programme of investment to address all inadequacies in drinking water parameters including THMs. By 2021 the utility plans to reduce the number of schemes on the RAL to zero with an investment of €327 million in upgrading water supplies at risk from THMs.

THMs are chemicals formed by the reaction of naturally occurring dissolved organic material and chlorine which is used for disinfection in order to protect against pathogenic bacteria.

Work in Roscommon to secure high quality water supplies for over 19,000 people

Four water supplies in Co. Roscommon remain on the RAL where Irish Water has prioritised a programme of works to ensure their removal for the benefit of over 19,000 people. Works are progressing and are on target across the four supplies namely Ballinlough/Loughglynn, Grangemore, North East Regional WSS, and North Roscommon Regional WSS.

The boil water notice was lifted on the North East Regional scheme in September of last year. The scheme was placed on the boil water notice two and a half years ago following the detection of cryptosporidium in the water supply. Irish Water installed a temporary water treatment plant consisting of coagulation, containerised filtration and a UV disinfection system at Lisheen Lake. The water company said this is a temporary solution until the permanent water treatment plant is commissioned and fully operational.

Construction works on the long term solution for North East Roscommon are continuing and involves constructing a new water treatment plant and intake works which will abstract and treat water from a new source at Grange Lough. The treatment plant will ultimately replace the temporary plant in operation at Lisheen Lake. 

Once the permanent plant is commissioned, the temporary, containerised unit, which is portable, will be reused and deployed at future sites that require UV and/or filtration.

The Ballinlough/Loughglynn plant is on the RAL due to inadequate treatment for cryptosporidium, and the scheme is also on a Boil Water Notice since January 2016. Irish Water is planning to  resolve the issues by extending the Lough Mask Regional Water Supply Scheme to both the Ballinlough and Williamstown communities. The project is being fast-tracked to ensure it is delivered as quickly as possible and is due for completion at the end of 2017 with the works to supply Ballinlough a priority.

The Grangemore and North Roscommon schemes which collective supply water to over 10,000 people have periodically recorded elevated THM levels above the standard in the Drinking Water Regulations. Irish Water is currently upgrading the North Roscommon Regional Water Supply Scheme which also supplies consumers in the South Sligo region. Works are continuing to optimise the treatment process at the North Roscommon Water Treatment Works and these works are due for completion by the end of 2017.

The intention is to decommission the Grangemore Water Treatment Plant and supply customers from the Boyle/Ardcarne water supply scheme. The works are currently being planned and designed with completion due in 2018.

Nationally Irish Water has adopted a prioritised programme of works which will require an investment of €2 billion by 2021.

Speaking about the RAL, Irish Water’s Regional Compliance Specialist Pat O’Sullivan said:

“As a single utility Irish Water is able to conduct a comprehensive evaluation of the performance of Ireland’s drinking water production plants and where serious compliance challenges are found they can be tackled more effectively and efficiently. The decommissioning of smaller water treatment plants and rationalisation of water supply zones … could only be achieved by a single utility.”

The RAL is updated quarterly by the EPA for those water supplies where investment in treatment processes is required. Irish Water has a prioritised programme of investment for all schemes on the RAL.